Volatility spillovers and determinants of contagion: a case of BRICS equity and foreign exchange markets
- Authors: Nyopa, Tšepiso
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Masters , MCOM
- Identifier: http://hdl.handle.net/10962/164590 , vital:41146
- Description: Thesis (MSc)--Rhodes University, Faculty of Commerce, Economics and Economic History, 2020
- Full Text:
- Date Issued: 2020
- Authors: Nyopa, Tšepiso
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Masters , MCOM
- Identifier: http://hdl.handle.net/10962/164590 , vital:41146
- Description: Thesis (MSc)--Rhodes University, Faculty of Commerce, Economics and Economic History, 2020
- Full Text:
- Date Issued: 2020
Volcano correlations for the reactivity of surface-confined cobalt N4-macrocyclics for the electrocatalytic oxidation of 2-mercaptoacetate
- Claußen, Jan A, Ochoa, Gonzalo, Páez, Maritza, Costamagno, Juan, Gulppi, Miguel, Nyokong, Tebello, Bedioui, Fethi, Zagal, José H
- Authors: Claußen, Jan A , Ochoa, Gonzalo , Páez, Maritza , Costamagno, Juan , Gulppi, Miguel , Nyokong, Tebello , Bedioui, Fethi , Zagal, José H
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/268688 , vital:54222 , xlink:href="https://doi.org/10.1007/s10008-007-0336-y"
- Description: We have investigated the electrocatalytic activity of several substituted and unsubstituted cobalt–phthalocyanines of substituted tetraphenyl porphyrins and of vitamin B12, for the electro-oxidation of 2-mercaptoacetate, with the complexes pre-adsorbed on a pyrolytic graphite electrode. Several N4-macrocyclic were used to have a wide variety of Co(II)/(I) formal potentials. The electrocatalytic activity, measured as current at constant potential, increases with the Co(II)/(I) redox potential for porphyrins as Co–pentafluorotetraphenylporphyrin larger than Co–tetrasulfonatotetraphenylporphyrin larger than Co-2,2′,2″,2‴tetra-aminotetraphenylporphyrin and decreases for cobalt phthalocyanines as Co-3,4-octaethylhexyloxyphthalocyanine > Co–octamethoxyphthalocyanine > Co–tetranitrophthalocyanine Co–tetraaminophthalocyanine > Co–unsubstituted phthalocyanine > Co–tetrasulfonatophthalocyanine > Co–perfluorinated phthalocyanine. Vitamin B12 exhibits the maximum activity. A correlation of log I (at constant potential) versus the Co(II)/(I) formal potential of the catalysts gives a volcano curve. This clearly shows that the search for better catalysts for this reaction point to those N4-macrocyclic complexes with Co(II)/(I) formal potentials close to −0.84 V versus SCE, which correspond to an optimum situation for the interaction of the thiol with the active site.
- Full Text:
- Date Issued: 2008
- Authors: Claußen, Jan A , Ochoa, Gonzalo , Páez, Maritza , Costamagno, Juan , Gulppi, Miguel , Nyokong, Tebello , Bedioui, Fethi , Zagal, José H
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/268688 , vital:54222 , xlink:href="https://doi.org/10.1007/s10008-007-0336-y"
- Description: We have investigated the electrocatalytic activity of several substituted and unsubstituted cobalt–phthalocyanines of substituted tetraphenyl porphyrins and of vitamin B12, for the electro-oxidation of 2-mercaptoacetate, with the complexes pre-adsorbed on a pyrolytic graphite electrode. Several N4-macrocyclic were used to have a wide variety of Co(II)/(I) formal potentials. The electrocatalytic activity, measured as current at constant potential, increases with the Co(II)/(I) redox potential for porphyrins as Co–pentafluorotetraphenylporphyrin larger than Co–tetrasulfonatotetraphenylporphyrin larger than Co-2,2′,2″,2‴tetra-aminotetraphenylporphyrin and decreases for cobalt phthalocyanines as Co-3,4-octaethylhexyloxyphthalocyanine > Co–octamethoxyphthalocyanine > Co–tetranitrophthalocyanine Co–tetraaminophthalocyanine > Co–unsubstituted phthalocyanine > Co–tetrasulfonatophthalocyanine > Co–perfluorinated phthalocyanine. Vitamin B12 exhibits the maximum activity. A correlation of log I (at constant potential) versus the Co(II)/(I) formal potential of the catalysts gives a volcano curve. This clearly shows that the search for better catalysts for this reaction point to those N4-macrocyclic complexes with Co(II)/(I) formal potentials close to −0.84 V versus SCE, which correspond to an optimum situation for the interaction of the thiol with the active site.
- Full Text:
- Date Issued: 2008
Voltammetric behavior of cysteine and metallothionein on cobalt (II) tetrasulfonated phthalocyanine modified glassy carbon electrodes
- Limson, Janice, Nyokong, Tebello
- Authors: Limson, Janice , Nyokong, Tebello
- Date: 1997
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/293346 , vital:57077 , xlink:href="https://doi.org/10.1002/elan.1140090314"
- Description: Cysteine, and rat Cd, Zn-metallothionein (Cd, Zn-MT) have been studied electrochemically at glassy carbon electrodes modified with cobalt(II) tetrasulfonated phthalocyanine, [CoIITSPc]4−, where Pc(2-) = phthalocyanine dianion. The electrode was modified by electrodeposition of [CoIITSPc]4−. The anodic currents for the oxidation of cysteine on these electrodes are observed at 0.82 V (vs. Ag/AgCl) in acidic media. The anodic currents for the oxidation of Cd, Zn-MT are observed at 0.90 V at pH 8.4 (Tris buffer).
- Full Text:
- Date Issued: 1997
- Authors: Limson, Janice , Nyokong, Tebello
- Date: 1997
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/293346 , vital:57077 , xlink:href="https://doi.org/10.1002/elan.1140090314"
- Description: Cysteine, and rat Cd, Zn-metallothionein (Cd, Zn-MT) have been studied electrochemically at glassy carbon electrodes modified with cobalt(II) tetrasulfonated phthalocyanine, [CoIITSPc]4−, where Pc(2-) = phthalocyanine dianion. The electrode was modified by electrodeposition of [CoIITSPc]4−. The anodic currents for the oxidation of cysteine on these electrodes are observed at 0.82 V (vs. Ag/AgCl) in acidic media. The anodic currents for the oxidation of Cd, Zn-MT are observed at 0.90 V at pH 8.4 (Tris buffer).
- Full Text:
- Date Issued: 1997
Voltammetric characterisation of the self-assembled monolayers (SAMs) of benzyl-and dodecyl-mercapto tetra substituted metallophthalocyanines complexes
- Agboola, Bolade, Westbroek, Philippe, Ozoemena, Kenneth I, Nyokong, Tebello
- Authors: Agboola, Bolade , Westbroek, Philippe , Ozoemena, Kenneth I , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281414 , vital:55723 , xlink:href="https://doi.org/10.1016/j.elecom.2006.08.047"
- Description: Voltammetric characterisations of cobalt, iron, manganese, nickel and zinc phthalocyanine complexes tetra substituted with benzyl- and dodecyl-mercapto ring substituents and immobilisation on gold electrodes via the self-assembling technique are presented. The self-assembled films are stable and showed blocking characteristics towards the following Faradaic processes; gold surface oxidation, under potential deposition of copper and solution redox chemistry of [Fe(H2O)6 3+ ]/[Fe(H2O)6 2+ ]. The solution chemistry of [Fe(CN)6]−3/[Fe(CN)6]−4 redox process was used to study the orientation of the CoPcs-SAMs and this revealed a possible deviation from flat orientation of the complexes on the gold electrodes when the SAM formation times were greater than 24 h. For SAM formation time at 24 and 48 h, CoTDMPc-SAM showed more inhibition of the [Fe(CN)6]−3/[Fe(CN)6]−4 redox process than the CoTBMPc-SAM counterpart, indicating more blocking characteristics of the dodecylmercapto ring substituents compared to the benzylmercapto counterpart. To avoid SAM desorption, the potential application should be limited to −0.2 to +0.8 V vs. Ag∣AgCl (NaCl, sat’d) in acidic and neutral pH.
- Full Text:
- Date Issued: 2007
- Authors: Agboola, Bolade , Westbroek, Philippe , Ozoemena, Kenneth I , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281414 , vital:55723 , xlink:href="https://doi.org/10.1016/j.elecom.2006.08.047"
- Description: Voltammetric characterisations of cobalt, iron, manganese, nickel and zinc phthalocyanine complexes tetra substituted with benzyl- and dodecyl-mercapto ring substituents and immobilisation on gold electrodes via the self-assembling technique are presented. The self-assembled films are stable and showed blocking characteristics towards the following Faradaic processes; gold surface oxidation, under potential deposition of copper and solution redox chemistry of [Fe(H2O)6 3+ ]/[Fe(H2O)6 2+ ]. The solution chemistry of [Fe(CN)6]−3/[Fe(CN)6]−4 redox process was used to study the orientation of the CoPcs-SAMs and this revealed a possible deviation from flat orientation of the complexes on the gold electrodes when the SAM formation times were greater than 24 h. For SAM formation time at 24 and 48 h, CoTDMPc-SAM showed more inhibition of the [Fe(CN)6]−3/[Fe(CN)6]−4 redox process than the CoTBMPc-SAM counterpart, indicating more blocking characteristics of the dodecylmercapto ring substituents compared to the benzylmercapto counterpart. To avoid SAM desorption, the potential application should be limited to −0.2 to +0.8 V vs. Ag∣AgCl (NaCl, sat’d) in acidic and neutral pH.
- Full Text:
- Date Issued: 2007
Voltammetric characterization of the self-assembled monolayer (SAM) of octabutylthiophthalocyaninatoiron (II)
- Ozoemena,Kenneth, Nyokong, Tebello
- Authors: Ozoemena,Kenneth , Nyokong, Tebello
- Date: 2002
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/290419 , vital:56748 , xlink:href="https://doi.org/10.1016/S0013-4686(02)00362-6"
- Description: The fabrication of a self-assembled monolayer (SAM) of 2,3,9,10,16,17,23,24-octa (butylthio)-phthalocyaninatoiron(II) [FePc(SBu)8] on gold electrode is described. The integrity of the SAM, with respect to its ability to block certain Faradaic processes, is interrogated using cyclic voltammetric experiments in aqueous solutions. The experiments show that this SAM provide an excellent blocking capability to the Faradaic processes emanating from gold surface oxidation, underpotential deposition (UPD) of copper and redox chemistry of Fe(NH4)(SO4)2 in HClO4. It is revealed by cyclic voltammetry that an ill-defined reversible couple of the SAM of FePc(SBu)8 can be greatly improved by a simple repetitive cycling of the modified electrode in a DMF solution containing TBAP within a short space of time (ca. 2 min). This ‘activation’ process provides good information concerning the surface coverage and orientation of the monolayer. The reversible redox wave shows a potential shift of about −57 mV per pH in the pH range of 2–9. A preliminary investigation indicates that FePc(SBu)8-SAM modified gold electrode shows electrocatalytic activity toward the oxidation of L-cysteine in acidic medium. The monolayer is stable and easily reproducible. However, due to its susceptibility to destruction via oxidative and reductive desorptions, its potential application as an electrochemical sensor would be much better in acidic and neutral than alkaline environments.
- Full Text:
- Date Issued: 2002
- Authors: Ozoemena,Kenneth , Nyokong, Tebello
- Date: 2002
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/290419 , vital:56748 , xlink:href="https://doi.org/10.1016/S0013-4686(02)00362-6"
- Description: The fabrication of a self-assembled monolayer (SAM) of 2,3,9,10,16,17,23,24-octa (butylthio)-phthalocyaninatoiron(II) [FePc(SBu)8] on gold electrode is described. The integrity of the SAM, with respect to its ability to block certain Faradaic processes, is interrogated using cyclic voltammetric experiments in aqueous solutions. The experiments show that this SAM provide an excellent blocking capability to the Faradaic processes emanating from gold surface oxidation, underpotential deposition (UPD) of copper and redox chemistry of Fe(NH4)(SO4)2 in HClO4. It is revealed by cyclic voltammetry that an ill-defined reversible couple of the SAM of FePc(SBu)8 can be greatly improved by a simple repetitive cycling of the modified electrode in a DMF solution containing TBAP within a short space of time (ca. 2 min). This ‘activation’ process provides good information concerning the surface coverage and orientation of the monolayer. The reversible redox wave shows a potential shift of about −57 mV per pH in the pH range of 2–9. A preliminary investigation indicates that FePc(SBu)8-SAM modified gold electrode shows electrocatalytic activity toward the oxidation of L-cysteine in acidic medium. The monolayer is stable and easily reproducible. However, due to its susceptibility to destruction via oxidative and reductive desorptions, its potential application as an electrochemical sensor would be much better in acidic and neutral than alkaline environments.
- Full Text:
- Date Issued: 2002
Voltammetric detection of vitamin B1 at carbon paste electrodes and its determination in tablets
- Oni, Joshua, Westbroek, Philippe, Nyokong, Tebello
- Authors: Oni, Joshua , Westbroek, Philippe , Nyokong, Tebello
- Date: 2002
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/289692 , vital:56663 , xlink:href="https://doi.org/10.1002/1521-4109(200209)14"
- Description: The voltammetric behavior of vitamin B1 in alkaline medium at carbon paste electrode (CPE) is discussed. A method based on cyclic voltammetry for the determination of vitamin B1 at carbon paste electrode modified with manganese phthalocyanine (MnPc-CPE) is presented. In pH 10 buffer, the modified electrode showed catalytic activity towards the oxidation of vitamin B1 by considerably increasing the oxidation current of one of the observed waves compared to the oxidation current obtained at an unmodified electrode. The modified electrode was stable towards the determination of vitamin B1 compared to the unmodified electrode that is completely poisoned after a few scans. A linear relationship between the oxidation current and the concentration of vitamin B1 in solution was observed. The detection limit for vitamin B1 at the modified electrode was of the order of 10−5 mol dm−3. Commercial vitamin B1 tablets were analyzed using the modified electrodes.
- Full Text:
- Date Issued: 2002
- Authors: Oni, Joshua , Westbroek, Philippe , Nyokong, Tebello
- Date: 2002
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/289692 , vital:56663 , xlink:href="https://doi.org/10.1002/1521-4109(200209)14"
- Description: The voltammetric behavior of vitamin B1 in alkaline medium at carbon paste electrode (CPE) is discussed. A method based on cyclic voltammetry for the determination of vitamin B1 at carbon paste electrode modified with manganese phthalocyanine (MnPc-CPE) is presented. In pH 10 buffer, the modified electrode showed catalytic activity towards the oxidation of vitamin B1 by considerably increasing the oxidation current of one of the observed waves compared to the oxidation current obtained at an unmodified electrode. The modified electrode was stable towards the determination of vitamin B1 compared to the unmodified electrode that is completely poisoned after a few scans. A linear relationship between the oxidation current and the concentration of vitamin B1 in solution was observed. The detection limit for vitamin B1 at the modified electrode was of the order of 10−5 mol dm−3. Commercial vitamin B1 tablets were analyzed using the modified electrodes.
- Full Text:
- Date Issued: 2002
Voltammetric detection of vitamin B1 at carbon paste electrodes and its determination in tablets
- Oni, Joshua, Westbroek, Philippe, Nyokong, Tebello
- Authors: Oni, Joshua , Westbroek, Philippe , Nyokong, Tebello
- Date: 2002
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/289678 , vital:56662 , xlink:href="https://doi.org/10.1002/1521-4109(200209)14"
- Description: The voltammetric behavior of vitamin B1 in alkaline medium at carbon paste electrode (CPE) is discussed. A method based on cyclic voltammetry for the determination of vitamin B1 at carbon paste electrode modified with manganese phthalocyanine (MnPc-CPE) is presented. In pH 10 buffer, the modified electrode showed catalytic activity towards the oxidation of vitamin B1 by considerably increasing the oxidation current of one of the observed waves compared to the oxidation current obtained at an unmodified electrode. The modified electrode was stable towards the determination of vitamin B1 compared to the unmodified electrode that is completely poisoned after a few scans. A linear relationship between the oxidation current and the concentration of vitamin B1 in solution was observed. The detection limit for vitamin B1 at the modified electrode was of the order of 10−5 mol dm−3. Commercial vitamin B1 tablets were analyzed using the modified electrodes.
- Full Text:
- Date Issued: 2002
- Authors: Oni, Joshua , Westbroek, Philippe , Nyokong, Tebello
- Date: 2002
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/289678 , vital:56662 , xlink:href="https://doi.org/10.1002/1521-4109(200209)14"
- Description: The voltammetric behavior of vitamin B1 in alkaline medium at carbon paste electrode (CPE) is discussed. A method based on cyclic voltammetry for the determination of vitamin B1 at carbon paste electrode modified with manganese phthalocyanine (MnPc-CPE) is presented. In pH 10 buffer, the modified electrode showed catalytic activity towards the oxidation of vitamin B1 by considerably increasing the oxidation current of one of the observed waves compared to the oxidation current obtained at an unmodified electrode. The modified electrode was stable towards the determination of vitamin B1 compared to the unmodified electrode that is completely poisoned after a few scans. A linear relationship between the oxidation current and the concentration of vitamin B1 in solution was observed. The detection limit for vitamin B1 at the modified electrode was of the order of 10−5 mol dm−3. Commercial vitamin B1 tablets were analyzed using the modified electrodes.
- Full Text:
- Date Issued: 2002
Voltammetric determination of nitric oxide on cobalt phthalocyanine modified microelectrodes
- Vilakazi, Sibulelo Lea, Nyokong, Tebello
- Authors: Vilakazi, Sibulelo Lea , Nyokong, Tebello
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/291629 , vital:56893 , xlink:href="https://doi.org/10.1016/S0022-0728(01)00583-6"
- Description: The catalytic activity of a carbon fiber microelectrode modified with cobalt phthalocyanine (CoPc-ME) for the detection of nitric oxide in the presence of possible interfering molecules (dopamine and serotonin) is examined. A linear plot is observed for the variation of the catalytic currents with NO concentration in the presence of excess dopamine and serotonin, showing that NO may be determined in the presence of these molecules. However, oxidation currents due to serotonin were found to decrease with increase in NO concentration. The CoPc-ME could also detect NO added to blood or its components, the oxidation currents for NO, however, decreased rapidly with time. The decrease in currents was slower in blood serum, followed by whole blood, with a faster decrease being observed in blood plasma.
- Full Text:
- Date Issued: 2001
- Authors: Vilakazi, Sibulelo Lea , Nyokong, Tebello
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/291629 , vital:56893 , xlink:href="https://doi.org/10.1016/S0022-0728(01)00583-6"
- Description: The catalytic activity of a carbon fiber microelectrode modified with cobalt phthalocyanine (CoPc-ME) for the detection of nitric oxide in the presence of possible interfering molecules (dopamine and serotonin) is examined. A linear plot is observed for the variation of the catalytic currents with NO concentration in the presence of excess dopamine and serotonin, showing that NO may be determined in the presence of these molecules. However, oxidation currents due to serotonin were found to decrease with increase in NO concentration. The CoPc-ME could also detect NO added to blood or its components, the oxidation currents for NO, however, decreased rapidly with time. The decrease in currents was slower in blood serum, followed by whole blood, with a faster decrease being observed in blood plasma.
- Full Text:
- Date Issued: 2001
Voltammetry and electrochemical impedance spectroscopy of gold electrodes modified with CdTe quantum dots and their conjugates with nickel tetraamino phthalocyanine
- Khene, Samson, Moeno, Sharon, Nyokong, Tebello
- Authors: Khene, Samson , Moeno, Sharon , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/247187 , vital:51554 , xlink:href="https://doi.org/10.1016/j.poly.2011.06.002"
- Description: This work reports on the synthesis of conjugates of cadmium telluride quantum dots (CdTe-QDs) caped with thioglycolic acid and peripherally substituted nickel tetraamino phthalocyanine (NiTAPc) complex. The conjugates are characterized using cyclic (CV) and differential pulse (DPV) voltammetries, electrochemical impedance spectroscopy, X-ray powder diffraction, infrared spectroscopy, Raman spectroscopy, atomic force microscopy and time correlated single photon counting. CV and DPV show that NiTAPc stabilizes the CdTe QDs against oxidation to metallic products.
- Full Text:
- Date Issued: 2011
- Authors: Khene, Samson , Moeno, Sharon , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/247187 , vital:51554 , xlink:href="https://doi.org/10.1016/j.poly.2011.06.002"
- Description: This work reports on the synthesis of conjugates of cadmium telluride quantum dots (CdTe-QDs) caped with thioglycolic acid and peripherally substituted nickel tetraamino phthalocyanine (NiTAPc) complex. The conjugates are characterized using cyclic (CV) and differential pulse (DPV) voltammetries, electrochemical impedance spectroscopy, X-ray powder diffraction, infrared spectroscopy, Raman spectroscopy, atomic force microscopy and time correlated single photon counting. CV and DPV show that NiTAPc stabilizes the CdTe QDs against oxidation to metallic products.
- Full Text:
- Date Issued: 2011
Vulamasango Singene: sociological analysis of a rural social movement
- Authors: Kirchmann, Gail Lynne
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/425132 , vital:72213
- Description: This dissertation tests the claim made by a large membership-based organisation that it is a social movement. The organisation, Vulamasango Singene (VS) operates across the rural areas of large parts of the Eastern Cape Province. It has, for twenty years, advocated for the re-opening of land restitution claims for a specific category of forced removal known as “betterment”. This study provides an analysis of an organisation that has yet to achieve its objective in spite of sufficient financial resources, logistical and strategic support, numeric strength and the legal clarity of its demand. The research is situated within the framework of social movement theory. The study examined the origins, institutional infrastructure, demographic make-up, activities and culture of VS. These were analysed against four components that are identified in the literature as key characteristics of a social movement. These are: (i) informal networks (as opposed to structured and managed engagements); (ii) a plurality of actors (as opposed to a homogenous grouping); (iii) mobilising around issues of conflict; and (iv) sharing common beliefs and demonstrating solidarity. Data were gathered through an archival study and field research. Semi-structured interviews were carried out with a sample of VS’s leadership, and staff of the non-governmental organisation in which VS originated, as well as expert informants in the land reform arena. The findings with respect to each of the criteria were: (i) VS’s structure was rigid and internal communication was largely formal. (ii) There was almost no demographic or political diversity within VS. (iii) VS had, in the past, mobilised around issues of conflict, but there had been no mobilisation for ten years. (iv) While there was some evidence of sharing common beliefs and demonstrating solidarity, this was limited. The conclusion reached was that VS is not a social movement. This does not imply that VS is not an important democratic or representative organisation. It does, however, provide a theoretical position from which VS, and other organisations, can direct further action. The study touched on the relationship between northern donors, local professional NGOs and grassroots organisations in South Africa. Interactions among these institutions impact on the way that organisations and social movements develop. Comparisons with other similar organisations were made and similarities and differences were highlighted. It was suggested that, because of the importance of the issue, further research in this regard is necessary. , Thesis (MA) -- Faculty of Humanities, Sociology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Kirchmann, Gail Lynne
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/425132 , vital:72213
- Description: This dissertation tests the claim made by a large membership-based organisation that it is a social movement. The organisation, Vulamasango Singene (VS) operates across the rural areas of large parts of the Eastern Cape Province. It has, for twenty years, advocated for the re-opening of land restitution claims for a specific category of forced removal known as “betterment”. This study provides an analysis of an organisation that has yet to achieve its objective in spite of sufficient financial resources, logistical and strategic support, numeric strength and the legal clarity of its demand. The research is situated within the framework of social movement theory. The study examined the origins, institutional infrastructure, demographic make-up, activities and culture of VS. These were analysed against four components that are identified in the literature as key characteristics of a social movement. These are: (i) informal networks (as opposed to structured and managed engagements); (ii) a plurality of actors (as opposed to a homogenous grouping); (iii) mobilising around issues of conflict; and (iv) sharing common beliefs and demonstrating solidarity. Data were gathered through an archival study and field research. Semi-structured interviews were carried out with a sample of VS’s leadership, and staff of the non-governmental organisation in which VS originated, as well as expert informants in the land reform arena. The findings with respect to each of the criteria were: (i) VS’s structure was rigid and internal communication was largely formal. (ii) There was almost no demographic or political diversity within VS. (iii) VS had, in the past, mobilised around issues of conflict, but there had been no mobilisation for ten years. (iv) While there was some evidence of sharing common beliefs and demonstrating solidarity, this was limited. The conclusion reached was that VS is not a social movement. This does not imply that VS is not an important democratic or representative organisation. It does, however, provide a theoretical position from which VS, and other organisations, can direct further action. The study touched on the relationship between northern donors, local professional NGOs and grassroots organisations in South Africa. Interactions among these institutions impact on the way that organisations and social movements develop. Comparisons with other similar organisations were made and similarities and differences were highlighted. It was suggested that, because of the importance of the issue, further research in this regard is necessary. , Thesis (MA) -- Faculty of Humanities, Sociology, 2023
- Full Text:
- Date Issued: 2023-10-13
Vulnerability assessment of wetland ecosystems to water demand, climate variability and land-use/cover change: The case of Die Vlei wetland, Eastern Cape province, South Africa
- Gwena, Kudzanai Rosebud https://orcid.org/0000-0002-1032-8937
- Authors: Gwena, Kudzanai Rosebud https://orcid.org/0000-0002-1032-8937
- Date: 2021-09
- Subjects: Water-supply , Climate change mitigation
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/22688 , vital:52656
- Description: Water scarcity is a major challenge in many different countries, particularly arid and or semi-arid like South Africa. Wetlands are one of the freshwater ecosystems that may assist in alleviating water scarcity because they are valuable not only as a water source for humans but also as an ecosystem of animals and plant species. However, wetlands have been experiencing rapid rates of vulnerability/risk due to alterations by population growth leading to enhanced water demand, climate variability, and human activities leading to land cover/land-use changes. Geographical Information Systems (GIS) and Remote Sensing (RS) are less financially taxing methods useful in studying water scarcity, as shown in this study. The study begins with a literature review presentation based on a desk study from predominantly academic publications and additional municipal and consultancy reports on the wetland ecosystem’s vulnerability/risk and focuses on applying GIS & RS in related studies. After that, the study conducts a vulnerability assessment using the Ramsar Convention’s wetland vulnerability assessment using the theoretical framework stages using GIS and RS technologies. The study hypothesizes that water demand, climate variability, and land-use/cover changes (LULC) are the tri-factor responsible for wetland vulnerability. It begins the assessment by first quantifying wetland water demand using the wetland water budget, ecosystem services and the Penman-Montheith-FAO (ETo) evapotranspiration index. Secondly, objectively representing climate variability on wetland vulnerability using trend analysis to measure rainfall and temperature variability. Thirdly, reconstructing LULC changes from multi-date remotely sensed SPOT imagery over ten years from 2007 to 2017 to identify and monitor impacts of trends. The vulnerability was assessed through a Principle Component Analysis (PCA) that identified relevant variables and Multi-Criteria Evaluation (MCE) to evaluate the wetland’s exposure. The study concludes that there is evidence of a possible increase in water demand whilst climate variability, which is estimated to have a 39% contribution to the wetland dynamics, is characterised by a decrease in precipitation and an increase in temperatures. Lastly, LULC trends showed a marked increase in domestic and commercial farming, and farming has been identified as a wetland stressor of note. , Thesis (MPhil) -- Faculty of Science and Agriculture, 2021
- Full Text:
- Date Issued: 2021-09
- Authors: Gwena, Kudzanai Rosebud https://orcid.org/0000-0002-1032-8937
- Date: 2021-09
- Subjects: Water-supply , Climate change mitigation
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/22688 , vital:52656
- Description: Water scarcity is a major challenge in many different countries, particularly arid and or semi-arid like South Africa. Wetlands are one of the freshwater ecosystems that may assist in alleviating water scarcity because they are valuable not only as a water source for humans but also as an ecosystem of animals and plant species. However, wetlands have been experiencing rapid rates of vulnerability/risk due to alterations by population growth leading to enhanced water demand, climate variability, and human activities leading to land cover/land-use changes. Geographical Information Systems (GIS) and Remote Sensing (RS) are less financially taxing methods useful in studying water scarcity, as shown in this study. The study begins with a literature review presentation based on a desk study from predominantly academic publications and additional municipal and consultancy reports on the wetland ecosystem’s vulnerability/risk and focuses on applying GIS & RS in related studies. After that, the study conducts a vulnerability assessment using the Ramsar Convention’s wetland vulnerability assessment using the theoretical framework stages using GIS and RS technologies. The study hypothesizes that water demand, climate variability, and land-use/cover changes (LULC) are the tri-factor responsible for wetland vulnerability. It begins the assessment by first quantifying wetland water demand using the wetland water budget, ecosystem services and the Penman-Montheith-FAO (ETo) evapotranspiration index. Secondly, objectively representing climate variability on wetland vulnerability using trend analysis to measure rainfall and temperature variability. Thirdly, reconstructing LULC changes from multi-date remotely sensed SPOT imagery over ten years from 2007 to 2017 to identify and monitor impacts of trends. The vulnerability was assessed through a Principle Component Analysis (PCA) that identified relevant variables and Multi-Criteria Evaluation (MCE) to evaluate the wetland’s exposure. The study concludes that there is evidence of a possible increase in water demand whilst climate variability, which is estimated to have a 39% contribution to the wetland dynamics, is characterised by a decrease in precipitation and an increase in temperatures. Lastly, LULC trends showed a marked increase in domestic and commercial farming, and farming has been identified as a wetland stressor of note. , Thesis (MPhil) -- Faculty of Science and Agriculture, 2021
- Full Text:
- Date Issued: 2021-09
Wage differentials by sector and gender in Botswana
- Authors: Motswapong, Masedi
- Date: 2023-04
- Subjects: Wage differentials -- Botswana , Wage Decomposition
- Language: English
- Type: Doctoral's theses , text
- Identifier: http://hdl.handle.net/10948/62128 , vital:71998
- Description: The study examines wage differentials in the public and private sectors and gender wage gaps within these sectors in Botswana. Raw data from three nationally representative surveys collected is used. These surveys include the 2005/06 Labour force, the 2015/16 Multi-Topic Household and the 2019 Quarterly Multi-Topic. To address the set objectives, the study utilises the quantile regression model and decomposition methods proposed by Firpo, Fortin and Lemieux (2009) and further used the reweighted RIF-OLS OaxacaBlinder decomposition method proposed by Rios-Avila (2020). Results from three surveys demonstrate evidence of wage inequalities in Botswana. Findings revealed that the wage differential in the public and private sectors has weakened over the years, though it is still a significant concern. The public-private sector wage gap decreased from 72% in 2005/06 to 56% in 2019. However, a different trend is observed in the gender wage differentials, where the gap gradually increased over time. Gender wage gaps in the public sector were 4% in 2005/06; in 2015/16, the gap increased to 27% and 49% in 2019. On the other hand, in the private sector, the average wages were 7.34 and 6.98 for males and females in 2005/06, respectively, implying a wage gap of 35%. This trend holds for the other two samples. The gender wage gap in 2015/16 fell to 23% and increased to 28% in 2019. Results from the quantile regression estimates show that returns to education differ in both the sectoral and gender sections. Further, for males and females, returns for education tend to rise as the education level increases. Returns for education for the private sector are higher than for the public sector. For gender wage differences, education returns for females are higher than for males at all levels, supporting findings that females are more educated on average than males. For decomposition results, findings show that observed characteristics, such as education levels, negatively affect wages at the lower levels and positively at other parts of the distribution in the sectoral wage section. For the gender wage gap section, results show that workers’ characteristics had mixed contributions to the wage gap; it narrows the gap at the lower levels and widens it at higher levels of the wage distribution. Further, results suggest the presence of labour market discrimination and evidence of the “sticky-floor” viii effect in both sectors. Additionally, findings from the reweighting RIF-Oaxaca estimates show that the public-private sector wage gap takes an inverted U-shaped distribution in different levels of the wage distribution. Similarly, composition effects positively affect the gap at lower levels, whereas wage structure effects affect the wage gap at the highest distribution level. Overall, the study’s findings have some significant policy recommendations. The study has indicated that the country has no policy to reduce or eliminate wage differentials in the labour market. Hence, Botswana policymakers need to formulate policies to eliminate wage inequalities. Furthermore, it is recommended that the government should continue investing in human capital development. Education is vital in bridging the wage gap within the labour market. Additionally, there is a need to promote tolerance within society and promote ways of appreciating women’s work. It is also recommended that males be encouraged to work in jobs where women are overrepresented. The study's findings contribute to the ongoing wage inequality debate, and it is hoped that the study will benefit policymakers in Botswana. , Thesis (PhD) -- Faculty of Faculty of Business and Economic Sciences, 2023
- Full Text:
- Date Issued: 2023-04
- Authors: Motswapong, Masedi
- Date: 2023-04
- Subjects: Wage differentials -- Botswana , Wage Decomposition
- Language: English
- Type: Doctoral's theses , text
- Identifier: http://hdl.handle.net/10948/62128 , vital:71998
- Description: The study examines wage differentials in the public and private sectors and gender wage gaps within these sectors in Botswana. Raw data from three nationally representative surveys collected is used. These surveys include the 2005/06 Labour force, the 2015/16 Multi-Topic Household and the 2019 Quarterly Multi-Topic. To address the set objectives, the study utilises the quantile regression model and decomposition methods proposed by Firpo, Fortin and Lemieux (2009) and further used the reweighted RIF-OLS OaxacaBlinder decomposition method proposed by Rios-Avila (2020). Results from three surveys demonstrate evidence of wage inequalities in Botswana. Findings revealed that the wage differential in the public and private sectors has weakened over the years, though it is still a significant concern. The public-private sector wage gap decreased from 72% in 2005/06 to 56% in 2019. However, a different trend is observed in the gender wage differentials, where the gap gradually increased over time. Gender wage gaps in the public sector were 4% in 2005/06; in 2015/16, the gap increased to 27% and 49% in 2019. On the other hand, in the private sector, the average wages were 7.34 and 6.98 for males and females in 2005/06, respectively, implying a wage gap of 35%. This trend holds for the other two samples. The gender wage gap in 2015/16 fell to 23% and increased to 28% in 2019. Results from the quantile regression estimates show that returns to education differ in both the sectoral and gender sections. Further, for males and females, returns for education tend to rise as the education level increases. Returns for education for the private sector are higher than for the public sector. For gender wage differences, education returns for females are higher than for males at all levels, supporting findings that females are more educated on average than males. For decomposition results, findings show that observed characteristics, such as education levels, negatively affect wages at the lower levels and positively at other parts of the distribution in the sectoral wage section. For the gender wage gap section, results show that workers’ characteristics had mixed contributions to the wage gap; it narrows the gap at the lower levels and widens it at higher levels of the wage distribution. Further, results suggest the presence of labour market discrimination and evidence of the “sticky-floor” viii effect in both sectors. Additionally, findings from the reweighting RIF-Oaxaca estimates show that the public-private sector wage gap takes an inverted U-shaped distribution in different levels of the wage distribution. Similarly, composition effects positively affect the gap at lower levels, whereas wage structure effects affect the wage gap at the highest distribution level. Overall, the study’s findings have some significant policy recommendations. The study has indicated that the country has no policy to reduce or eliminate wage differentials in the labour market. Hence, Botswana policymakers need to formulate policies to eliminate wage inequalities. Furthermore, it is recommended that the government should continue investing in human capital development. Education is vital in bridging the wage gap within the labour market. Additionally, there is a need to promote tolerance within society and promote ways of appreciating women’s work. It is also recommended that males be encouraged to work in jobs where women are overrepresented. The study's findings contribute to the ongoing wage inequality debate, and it is hoped that the study will benefit policymakers in Botswana. , Thesis (PhD) -- Faculty of Faculty of Business and Economic Sciences, 2023
- Full Text:
- Date Issued: 2023-04
WAIS-IV test performance in the South African context: a comparison between existing grade 12 WAIS-III norms with grade 12 WAIS-IV for populations that were educated in former-DET schools
- Klopper, Coenraad Christoffel
- Authors: Klopper, Coenraad Christoffel
- Date: 2014-12
- Subjects: Intelligence tests , Wechsler Adult Intelligence Scale , Psychological tests
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/25891 , vital:64561
- Description: Accurate IQ assessment in the field of psychology is a constant pursuit and an ethical requirement in the field of psychology. In the South African cross cultural context, the use of within group norms are very important in order to improve the accuracy and interpretive value of psychometric tests. This is due to differences between cultural groups in South Africa in terms of IQ test performance of which the biggest mediating factor is quality of education. Shuttleworth-Edwards et al. (2013), performed cross cultural normative research on the WAIS-III in which participants were stringently stratified for age, level of education, quality of education, race and language. The current study is a partial duplication of the WAIS-III normative study by Shuttleworth-Edwards et al. (2013). The sub-group in that study that indicated the most significant lowering relative to the US/UK standardisation of the WAIS-III was duplicated in this study and tested with the WAIS-IV. This group included participants stratified for race (Black South African), language (Xhosa speaking), level of education (Grade 12) and quality of education (previous Department of Education and Training (former-DET) schools). The WAIS-IV results of the current study were statistically compared with the WAIS-III results from Shuttleworth-Edwards et al. (2013). No statistically significant differences were found between the WAIS-III test performance and WAIS-IV test performance in terms of scaled score comparisons, index score comparisons and full scale index comparisons. Further comparisons were made between male and female and urban and rural participants. Significant differences were found between males and females on the verbal comprehension index. No significant differences were found between the urban and rural participants. , Thesis (MA) -- Faculty of Social Science and Humanities, 2021
- Full Text:
- Date Issued: 2014-12
- Authors: Klopper, Coenraad Christoffel
- Date: 2014-12
- Subjects: Intelligence tests , Wechsler Adult Intelligence Scale , Psychological tests
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/25891 , vital:64561
- Description: Accurate IQ assessment in the field of psychology is a constant pursuit and an ethical requirement in the field of psychology. In the South African cross cultural context, the use of within group norms are very important in order to improve the accuracy and interpretive value of psychometric tests. This is due to differences between cultural groups in South Africa in terms of IQ test performance of which the biggest mediating factor is quality of education. Shuttleworth-Edwards et al. (2013), performed cross cultural normative research on the WAIS-III in which participants were stringently stratified for age, level of education, quality of education, race and language. The current study is a partial duplication of the WAIS-III normative study by Shuttleworth-Edwards et al. (2013). The sub-group in that study that indicated the most significant lowering relative to the US/UK standardisation of the WAIS-III was duplicated in this study and tested with the WAIS-IV. This group included participants stratified for race (Black South African), language (Xhosa speaking), level of education (Grade 12) and quality of education (previous Department of Education and Training (former-DET) schools). The WAIS-IV results of the current study were statistically compared with the WAIS-III results from Shuttleworth-Edwards et al. (2013). No statistically significant differences were found between the WAIS-III test performance and WAIS-IV test performance in terms of scaled score comparisons, index score comparisons and full scale index comparisons. Further comparisons were made between male and female and urban and rural participants. Significant differences were found between males and females on the verbal comprehension index. No significant differences were found between the urban and rural participants. , Thesis (MA) -- Faculty of Social Science and Humanities, 2021
- Full Text:
- Date Issued: 2014-12
Was Myriophyllum spicatum L.(Haloragaceae) recently introduced to South Africa from Eurasia?
- Weyl, Philip S, Thum, RA, Moody, ML, Newman, RM, Coetzee, Julie A
- Authors: Weyl, Philip S , Thum, RA , Moody, ML , Newman, RM , Coetzee, Julie A
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/425463 , vital:72242 , xlink:href="https://doi.org/10.1016/j.aquabot.2015.09.003"
- Description: There is debate over the native or exotic status of Myriophyllum spicatum L. (Haloragaceae) in South Africa, which has important implications for developing and implementing management strategies. The aim of this study was to determine if M. spicatum was recently introduced from Eurasia by reconstructing the genetic relationships between South African and Eurasian M. spicatum using both a nuclear ribosomal (ITS1-5.8S-ITS2-26S) and a chloroplast intron (trnQ-rps16) sequence from 40 populations. For both these DNA markers, the South African populations were distinct from Eurasian populations, but always stemmed from a European origin. The data suggest that South African and European M. spicatum share a common ancestor, however the divergence of both markers are characteristic of a long period of isolation rather than a recent introduction from Europe. The genetic data from this study suggest that M. spicatum has not been introduced recently, but is most likely a native component of the South African flora.
- Full Text:
- Date Issued: 2016
- Authors: Weyl, Philip S , Thum, RA , Moody, ML , Newman, RM , Coetzee, Julie A
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/425463 , vital:72242 , xlink:href="https://doi.org/10.1016/j.aquabot.2015.09.003"
- Description: There is debate over the native or exotic status of Myriophyllum spicatum L. (Haloragaceae) in South Africa, which has important implications for developing and implementing management strategies. The aim of this study was to determine if M. spicatum was recently introduced from Eurasia by reconstructing the genetic relationships between South African and Eurasian M. spicatum using both a nuclear ribosomal (ITS1-5.8S-ITS2-26S) and a chloroplast intron (trnQ-rps16) sequence from 40 populations. For both these DNA markers, the South African populations were distinct from Eurasian populations, but always stemmed from a European origin. The data suggest that South African and European M. spicatum share a common ancestor, however the divergence of both markers are characteristic of a long period of isolation rather than a recent introduction from Europe. The genetic data from this study suggest that M. spicatum has not been introduced recently, but is most likely a native component of the South African flora.
- Full Text:
- Date Issued: 2016
Waste keratinous biomass valorization and characterization of keratinases produced by exiguobacteria species
- Authors: Dlume, Tutuka
- Date: 2021-02
- Subjects: Factory and trade waste -- Biodegradation , Bioremediation
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20695 , vital:46438
- Description: Keratinous wastes are emanating in a million tons, as by-products, from various agro-industrial processing plants. Consequently, they create a serious solid waste problem in the environment due to poor handling. Microbial keratinases are proteolytic enzymes that effectively participate in keratin-rich biomass hydrolyses such as feathers, nail, hair, hooves, and horns. Therefore, proper management of these wastes via recycling into useful products is ecologically imperative. Biodegradation of keratin-rich biomass has been identified as an economical and environmentally friendly way of transforming these recalcitrant agro wastes into useful products, hence the motivation for this study. Feather degrading bacterial strains previously isolated from a municipal dumpsite and coded as SSB-02 and SSB-03 was identified through 16S rDNA sequencing and phylogenetic analysis. The fermentation conditions for keratinase production were optimized. The protein and amino acids constituents of the hydrolyzed chicken feather were analyzed. The biochemical properties of the keratinase produced were determined. Also, the effect of laundry detergents on the stability of the keratinase was studied. The isolates coded as SSB-02 and SSB-03 showed a high percentage of sequence homology with Exguobacterium spp., hence they were identified as Exiguobacterium sp. FBH5 and Exiguobacterium acetylicum FHBD, respectively. Exiguobacterium sp. FBH5 showed the highest extracellular keratinase production of 934.58 ± 27.27 U/mL at 72 h of incubation; in optimized fermentation conditions that included pH (5.0), temperature (30 oC), and chicken feather (0.5percent, w/v). Similarly, E. acetylicum FHBD displayed optimal keratinase production of 1023.64 ± 25.71 U/mL at 120 h of fermentation and improved fermentation conditions that involved pH (3.0), temperature (35 oC) and chicken feathers (0.5-1.5percent; w/v). The amino acid analysis showed that arginine, aspartic acid and glutamic acid were the most abundant amino acids cleaved from the degradation of chicken feathers by Exiguobacterium sp. FBH5 at a respective concentration of 1.16, 1.28 and 1.45 (g/100g sample). Additionally, hydrolysate that emanated from E. indicum FHBD degradation of feather showed high concentrations of arginine, serine, aspartic acid, glutamic acid, and glycine at the respective concentration (g/100g sample) of 1.2, 1.12, 1.34, 1.58 and 1.29. The keratinases were optimally active at pH and temperature of 8.0 and 50 oC, respectively. EDTA and PMSF did not highly repress keratinolytic proteases' activity, and this inhibitory pattern suggests that they may belong to a mixed protease family. Keratinase from E. acetylicum FHBD was highly stable in the presence of SDS, with 99percent residual activity and displayed variable stability in other chemical agents tested. A similar stability pattern was observed with keratinase from Exiguobacterium sp. FBH5, although the enzyme lost about 40percent of its original activity in the presence of SDS. Evaluation of metal ion stability indicated that E. acetylicum FHBD keratinase was remarkably stable in the presence of Fe3+, Mg2+, Cu2+, Zn2+, and Ba2+, with residual activity of 94percent, 88percent, 89percent, 90percent, and 97percent, respectively. Similarly, Exiguobacterium sp. FBH5 keratinase was considerably stable after treatment with Co2+, K+, and Zn2+ as it displayed a residual activity of 85percent, 84percent and 93percent, respectively. The study of the keratinases stability in laundry detergents showed that E. acetylicum FHBD keratinolytic proteases was activated in the presence of Omo, Surf, Sunlight, and Pro wash after 60 min of pre-incubation compared to 30 min, with residual activity of 94 ± 2.94percent, 91 ± 2.53percent, 95 ± 2.89percent and 87 ± 2.89percent respectively. Likewise, Exiguobacterium sp. FBH5 keratinase activity was promoted after 60 min of incubation compared to 30 min, with a residual enzyme activity of 79percent, 84percent, 101percent, 103percent and 105percent and 106percent for Ariel, Surf, Prowash, Freewave, Sky and Evaklin, respectively. Therefore Exiguobacterium spp., demonstrated excellent keratinolytic potentials that could be exploited for sustainable development of bio-innovative products. The study keratinases' properties suggest their industrial and biotechnological application potentials, especially as bio-additive in the formulation of laundry detergents. , Thesis (MSc) -- Faculty of Science and Agriculture, 2021
- Full Text:
- Date Issued: 2021-02
- Authors: Dlume, Tutuka
- Date: 2021-02
- Subjects: Factory and trade waste -- Biodegradation , Bioremediation
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20695 , vital:46438
- Description: Keratinous wastes are emanating in a million tons, as by-products, from various agro-industrial processing plants. Consequently, they create a serious solid waste problem in the environment due to poor handling. Microbial keratinases are proteolytic enzymes that effectively participate in keratin-rich biomass hydrolyses such as feathers, nail, hair, hooves, and horns. Therefore, proper management of these wastes via recycling into useful products is ecologically imperative. Biodegradation of keratin-rich biomass has been identified as an economical and environmentally friendly way of transforming these recalcitrant agro wastes into useful products, hence the motivation for this study. Feather degrading bacterial strains previously isolated from a municipal dumpsite and coded as SSB-02 and SSB-03 was identified through 16S rDNA sequencing and phylogenetic analysis. The fermentation conditions for keratinase production were optimized. The protein and amino acids constituents of the hydrolyzed chicken feather were analyzed. The biochemical properties of the keratinase produced were determined. Also, the effect of laundry detergents on the stability of the keratinase was studied. The isolates coded as SSB-02 and SSB-03 showed a high percentage of sequence homology with Exguobacterium spp., hence they were identified as Exiguobacterium sp. FBH5 and Exiguobacterium acetylicum FHBD, respectively. Exiguobacterium sp. FBH5 showed the highest extracellular keratinase production of 934.58 ± 27.27 U/mL at 72 h of incubation; in optimized fermentation conditions that included pH (5.0), temperature (30 oC), and chicken feather (0.5percent, w/v). Similarly, E. acetylicum FHBD displayed optimal keratinase production of 1023.64 ± 25.71 U/mL at 120 h of fermentation and improved fermentation conditions that involved pH (3.0), temperature (35 oC) and chicken feathers (0.5-1.5percent; w/v). The amino acid analysis showed that arginine, aspartic acid and glutamic acid were the most abundant amino acids cleaved from the degradation of chicken feathers by Exiguobacterium sp. FBH5 at a respective concentration of 1.16, 1.28 and 1.45 (g/100g sample). Additionally, hydrolysate that emanated from E. indicum FHBD degradation of feather showed high concentrations of arginine, serine, aspartic acid, glutamic acid, and glycine at the respective concentration (g/100g sample) of 1.2, 1.12, 1.34, 1.58 and 1.29. The keratinases were optimally active at pH and temperature of 8.0 and 50 oC, respectively. EDTA and PMSF did not highly repress keratinolytic proteases' activity, and this inhibitory pattern suggests that they may belong to a mixed protease family. Keratinase from E. acetylicum FHBD was highly stable in the presence of SDS, with 99percent residual activity and displayed variable stability in other chemical agents tested. A similar stability pattern was observed with keratinase from Exiguobacterium sp. FBH5, although the enzyme lost about 40percent of its original activity in the presence of SDS. Evaluation of metal ion stability indicated that E. acetylicum FHBD keratinase was remarkably stable in the presence of Fe3+, Mg2+, Cu2+, Zn2+, and Ba2+, with residual activity of 94percent, 88percent, 89percent, 90percent, and 97percent, respectively. Similarly, Exiguobacterium sp. FBH5 keratinase was considerably stable after treatment with Co2+, K+, and Zn2+ as it displayed a residual activity of 85percent, 84percent and 93percent, respectively. The study of the keratinases stability in laundry detergents showed that E. acetylicum FHBD keratinolytic proteases was activated in the presence of Omo, Surf, Sunlight, and Pro wash after 60 min of pre-incubation compared to 30 min, with residual activity of 94 ± 2.94percent, 91 ± 2.53percent, 95 ± 2.89percent and 87 ± 2.89percent respectively. Likewise, Exiguobacterium sp. FBH5 keratinase activity was promoted after 60 min of incubation compared to 30 min, with a residual enzyme activity of 79percent, 84percent, 101percent, 103percent and 105percent and 106percent for Ariel, Surf, Prowash, Freewave, Sky and Evaklin, respectively. Therefore Exiguobacterium spp., demonstrated excellent keratinolytic potentials that could be exploited for sustainable development of bio-innovative products. The study keratinases' properties suggest their industrial and biotechnological application potentials, especially as bio-additive in the formulation of laundry detergents. , Thesis (MSc) -- Faculty of Science and Agriculture, 2021
- Full Text:
- Date Issued: 2021-02
Water conservation and water demand management in Buffalo City Metropolitan Municipality
- Authors: Mlomzale, Kwanele
- Date: 2021-04
- Subjects: Water conservation -- South Africa -- Buffalo City , Water demand management -- South Africa -- Buffalo City , Municipal services -- South Africa -- Buffalo City , Municipal services -- Law and legislation -- South Africa -- Buffalo City , Water-supply -- Management
- Language: English
- Type: thesis , text , Masters , MBA
- Identifier: http://hdl.handle.net/10962/177159 , vital:42795
- Description: Water is one of the scarce and constrained natural resource globally, and a necessity to every living creature, organism and the natural environment – it is the existence of life. Water, as an irreplaceable natural resource, plays a vital role in every country's development and prosperity, integrating socio-economic needs of both the present and future generation. Therefore, sustainable strategies and approaches or concepts are significant in ensuring that such a unique resource is preserved and conserved sustainably. Municipal environment or local government sphere creates a pivotal role in governing the use of water, through the provision of legislation, regulations and establishment of water conservation and water demand management strategies and plans. However, it has been established that there is a lack of integrated water resource management approach and planning in municipalities, creating concerns with regards to controlling the overutilisation of water and protection of water sources in general. The aim and goals of the study are to review Buffalo City Metropolitan Municipality's (BCMM) water conservation and water demand management (BCMM WC/WDM) development and implementation by, assessing the existing strategy related to water conservation and water demand management; constraints and opportunity identification; and provision of recommendations in improving the practices in the municipality. The study presents core theories and empirical studies relevant to the water conservation and water demand management, and also deals with theoretical framework found under the Natural Resource-Based View and its application to water conservation and water demand management concepts. A qualitative research design approach was used for the research, which is underpinned by a post-positivism paradigm. In terms of data collection, two methods were used in the study: (i) document study and secondary analysis; and (ii) semi-structured interviews with BCMM relevant officials. The study identified gaps and inconsistencies in the development and implementation of BCMM WC/WDM strategy, although the municipality has taken some step towards its implementation. However, the strives taken by BCMM in implementing water conservation and water demand management initiatives are acknowledged. The study provides recommendations related to the findings identified upon the data collection and fieldwork. The recommendation proposed by the study includes proper communicating the BCMM WC/WDM strategy to all relevant stakeholders, focus on reducing the non-revenue water, implementation of various project related to pressure management, encourage culture of using water efficiently through educational and community awareness campaigns, capacitation of BCMM including seeking financial support, continuous review of the strategy and exploring other water supply sources to relax the already constrained existing water sources. The limitations of the study compared to the broader scope of water conservation and water demand management aspects are highlighted and acknowledged. Thus, in the conclusion of this study, further future studies are suggested to explore other related aspects of water conservation and water demand management in BCMM. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2021
- Full Text:
- Date Issued: 2021-04
- Authors: Mlomzale, Kwanele
- Date: 2021-04
- Subjects: Water conservation -- South Africa -- Buffalo City , Water demand management -- South Africa -- Buffalo City , Municipal services -- South Africa -- Buffalo City , Municipal services -- Law and legislation -- South Africa -- Buffalo City , Water-supply -- Management
- Language: English
- Type: thesis , text , Masters , MBA
- Identifier: http://hdl.handle.net/10962/177159 , vital:42795
- Description: Water is one of the scarce and constrained natural resource globally, and a necessity to every living creature, organism and the natural environment – it is the existence of life. Water, as an irreplaceable natural resource, plays a vital role in every country's development and prosperity, integrating socio-economic needs of both the present and future generation. Therefore, sustainable strategies and approaches or concepts are significant in ensuring that such a unique resource is preserved and conserved sustainably. Municipal environment or local government sphere creates a pivotal role in governing the use of water, through the provision of legislation, regulations and establishment of water conservation and water demand management strategies and plans. However, it has been established that there is a lack of integrated water resource management approach and planning in municipalities, creating concerns with regards to controlling the overutilisation of water and protection of water sources in general. The aim and goals of the study are to review Buffalo City Metropolitan Municipality's (BCMM) water conservation and water demand management (BCMM WC/WDM) development and implementation by, assessing the existing strategy related to water conservation and water demand management; constraints and opportunity identification; and provision of recommendations in improving the practices in the municipality. The study presents core theories and empirical studies relevant to the water conservation and water demand management, and also deals with theoretical framework found under the Natural Resource-Based View and its application to water conservation and water demand management concepts. A qualitative research design approach was used for the research, which is underpinned by a post-positivism paradigm. In terms of data collection, two methods were used in the study: (i) document study and secondary analysis; and (ii) semi-structured interviews with BCMM relevant officials. The study identified gaps and inconsistencies in the development and implementation of BCMM WC/WDM strategy, although the municipality has taken some step towards its implementation. However, the strives taken by BCMM in implementing water conservation and water demand management initiatives are acknowledged. The study provides recommendations related to the findings identified upon the data collection and fieldwork. The recommendation proposed by the study includes proper communicating the BCMM WC/WDM strategy to all relevant stakeholders, focus on reducing the non-revenue water, implementation of various project related to pressure management, encourage culture of using water efficiently through educational and community awareness campaigns, capacitation of BCMM including seeking financial support, continuous review of the strategy and exploring other water supply sources to relax the already constrained existing water sources. The limitations of the study compared to the broader scope of water conservation and water demand management aspects are highlighted and acknowledged. Thus, in the conclusion of this study, further future studies are suggested to explore other related aspects of water conservation and water demand management in BCMM. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2021
- Full Text:
- Date Issued: 2021-04
Water governance and social equity in South Africa: a case study of Amathole District Municipality.
- Authors: Hutete, Clarity
- Date: 2022-03
- Subjects: Municipal water supply
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/21931 , vital:51844
- Description: South Africa has reformed its water governance to remedy the prominent disparities in water service provision that resulted from the legacy of apartheid. However, despite the new policy reforms and strategies adopted, inequities in water governance remain prevalent. Those residing in marginalised and poor rural areas are the most vulnerable and highly affected by this phenomenon. While this has been attributed to several factors, such as fragmentation of the water sector and lack of capacity, among other reasons, an analysis of the literature revealed that the absence of a water governance framework for social equity is highly prevalent in the context of Amathole District Municipality (ADM) where the research was conducted. Hence, the study's main objective was to develop a water governance framework for social equity that can be utilised to advise councils and policymakers on the attainment of social equity by water service providers at the local level. The study utilised the constructivist research philosophy by adopting a qualitative case study research design and an inductive research approach to address the research questions. Focus group discussions, semi-structured interviews, participant observations and document analysis were used to collect data. A total sample of thirty-four (n=34) participants was purposefully selected; twenty participants (n=20) participated in semi-structured interviews, while fourteen (n=14) participants were engaged through focus group discussions. Findings obtained from the thematic data analysis utilised revealed that while human rights principles and social equity values underpin South Africa’s water reforms, Amathole District Municipality is yet to fully absorb these foundational concepts into its water governance. The study revealed that this is largely attributed to a lack of meaningful participation, limited transparency and accountability in the processes and procedures of the municipality. Results also revealed that persistent inequities still exist in Amathole District Municipality as reflected by the unequal distribution of water services, inconsistency in services provision, lack of transparency and established procedures to guarantee procedural fairness and limited impact on interventions specifically in rural areas. Furthermore, the study revealed that the municipality’s efforts to address water inequities are highly undermined by various economic, environmental, socio- economic, and institutional governance factors. Therefore, the study recommended a Water Governance Framework for Social Equity (WGFSE) and proffered recommendations to enhance social equity for Amathole District Municipality and other municipalities with similar contexts. , Thesis (MPA) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2022-03
- Authors: Hutete, Clarity
- Date: 2022-03
- Subjects: Municipal water supply
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/21931 , vital:51844
- Description: South Africa has reformed its water governance to remedy the prominent disparities in water service provision that resulted from the legacy of apartheid. However, despite the new policy reforms and strategies adopted, inequities in water governance remain prevalent. Those residing in marginalised and poor rural areas are the most vulnerable and highly affected by this phenomenon. While this has been attributed to several factors, such as fragmentation of the water sector and lack of capacity, among other reasons, an analysis of the literature revealed that the absence of a water governance framework for social equity is highly prevalent in the context of Amathole District Municipality (ADM) where the research was conducted. Hence, the study's main objective was to develop a water governance framework for social equity that can be utilised to advise councils and policymakers on the attainment of social equity by water service providers at the local level. The study utilised the constructivist research philosophy by adopting a qualitative case study research design and an inductive research approach to address the research questions. Focus group discussions, semi-structured interviews, participant observations and document analysis were used to collect data. A total sample of thirty-four (n=34) participants was purposefully selected; twenty participants (n=20) participated in semi-structured interviews, while fourteen (n=14) participants were engaged through focus group discussions. Findings obtained from the thematic data analysis utilised revealed that while human rights principles and social equity values underpin South Africa’s water reforms, Amathole District Municipality is yet to fully absorb these foundational concepts into its water governance. The study revealed that this is largely attributed to a lack of meaningful participation, limited transparency and accountability in the processes and procedures of the municipality. Results also revealed that persistent inequities still exist in Amathole District Municipality as reflected by the unequal distribution of water services, inconsistency in services provision, lack of transparency and established procedures to guarantee procedural fairness and limited impact on interventions specifically in rural areas. Furthermore, the study revealed that the municipality’s efforts to address water inequities are highly undermined by various economic, environmental, socio- economic, and institutional governance factors. Therefore, the study recommended a Water Governance Framework for Social Equity (WGFSE) and proffered recommendations to enhance social equity for Amathole District Municipality and other municipalities with similar contexts. , Thesis (MPA) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2022-03
Water quality monitoring: a correlation Between the bacteriological quality of drinking water and Diarrhoeal prevalence within the Koukamma local municipality
- Authors: Jacobs, Nathan Elmar
- Date: 2022-04
- Subjects: Water quality monitoring stations -- Koukamma local municipality , Water quality management
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/58882 , vital:60244
- Description: Background: Various studies have linked water quality and the prevalence of diarrhoeal cases within developing countries globally. The Emanti water quality monitoring system (eWQMS), representing the Kou-Kamma Local Municipality (Eastern Cape, South Africa), has often yielded non-complaint microbiological drinking water quality results retrospectively. This study investigated the relationship between the bacteriological quality of drinking water and diarrhoeal prevalence in children under five years of age within the Kou-Kamma Local Municipality from 2012 to 2016. Methods: A quantitative, descriptive, and ecological study design was employed retrospectively within the Kou-Kamma Local Municipality. Retrospective data collected from the Emanti Water Quality Monitoring System (eWQMS) represented the bacteriological quality of drinking water within the study area from 2012 to 2016. Concurrently, secondary data from the District Health Information Management System of the Eastern Cape Department of Health: Kouga Local service area was collected. The data represented cases of diarrhoea with dehydration in children under five years of age, reported at public health facilities within the study area retrospectively (from 2012 to 2016). Statistical analyses (Spearman's Rank Correlation) determined the relationship between the bacteriological quality of drinking water and the prevalence of diarrhoea in children under five years as per the retrospective period. Water samples were also collected for 2017 and 2018 to determine the presence of enteric pathogens in the municipal drinking water supply. Results: The study found that the Kou-Kamma Local Municipality had an overall noncompliance rate of 47% for the municipal drinking water supplied to the community from 2012 to 2016 (retrospective period). The difference in failure proportion (noncompliance) of water samples for the four climatic seasons where statistically significant (p=0.004). A significant difference was observed between autumn and winter (p=0.003) and autumn and spring (p=0.025). The failure proportion of water samples for autumn was significantly higher (mean = 0.603231, sd = 0.19528237) compared to winter (mean = 0.316675, sd = 0.19649776) and spring (mean = 0.374495, sd = 0.20626332). No significant difference was observed for the failure proportion of water samples between the various years of the retrospective period xvi (p=0.416). Children under the age of five accounted for n=460 cases of diarrhoea with dehydration at the public health facilities for the retrospective period. The Kareedouw area (n=196) and Joubertina area (n=134) recorded the highest diarrhoeal cases reported for the study period. These two areas both had hospitals that operated 24 hours a day; however, the differences in cases reported between the two areas was not statistically significant (p=0.179). Diarrhoeal case data reported between the various years within the study period were significantly different (p<0.001). The observed differences were between 2012 and 2014 (p=0.008) and 2012 and 2015 (p=0.001). The differences in the cases of diarrhoea with dehydration, in children under five years of age, were not statistically significant for the four climatic seasons (p=0.121). The relationship between the failure proportion of water samples and the prevalence of diarrhoea with dehydration in children under five years of age was statistically significant (p=0.001). The results revealed a moderate positive relationship (rs=0.434) between the bacteriological quality of drinking water and the prevalence of cases of diarrhoea with dehydration. Water samples were collected at various sampling points for July 2017 and November 2018 and analysed for enteric pathogens. Vibrio cholerae, Salmonella sp. and Shigella sp. were detected in such water samples collected. The relationship between the failure proportion of water samples and the presence of enteric pathogens was not statistically significant (rs=0.56723, p=0.240). Conclusion: The overall bacteriological quality of drinking water within the municipality was poor and likely posed a potential health risk to consumers. The study further revealed a steep rise of diarrhoeal with dehydration prevalence in children under five years of age during 2013, which decreased slowly during the years to follow. A moderate, positive relationship existed between the failure proportion of water samples and diarrhoea with dehydration prevalence in children under five years of age (rs=0.434, p=0.001 ). Therefore, municipalities should improve their bulk water infrastructure and drinking water disinfecting methods while realising the need for increased awareness of water-borne disease prevention. , Thesis (MA) -- Faculty of Health Sciences, 2022
- Full Text:
- Date Issued: 2022-04
- Authors: Jacobs, Nathan Elmar
- Date: 2022-04
- Subjects: Water quality monitoring stations -- Koukamma local municipality , Water quality management
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/58882 , vital:60244
- Description: Background: Various studies have linked water quality and the prevalence of diarrhoeal cases within developing countries globally. The Emanti water quality monitoring system (eWQMS), representing the Kou-Kamma Local Municipality (Eastern Cape, South Africa), has often yielded non-complaint microbiological drinking water quality results retrospectively. This study investigated the relationship between the bacteriological quality of drinking water and diarrhoeal prevalence in children under five years of age within the Kou-Kamma Local Municipality from 2012 to 2016. Methods: A quantitative, descriptive, and ecological study design was employed retrospectively within the Kou-Kamma Local Municipality. Retrospective data collected from the Emanti Water Quality Monitoring System (eWQMS) represented the bacteriological quality of drinking water within the study area from 2012 to 2016. Concurrently, secondary data from the District Health Information Management System of the Eastern Cape Department of Health: Kouga Local service area was collected. The data represented cases of diarrhoea with dehydration in children under five years of age, reported at public health facilities within the study area retrospectively (from 2012 to 2016). Statistical analyses (Spearman's Rank Correlation) determined the relationship between the bacteriological quality of drinking water and the prevalence of diarrhoea in children under five years as per the retrospective period. Water samples were also collected for 2017 and 2018 to determine the presence of enteric pathogens in the municipal drinking water supply. Results: The study found that the Kou-Kamma Local Municipality had an overall noncompliance rate of 47% for the municipal drinking water supplied to the community from 2012 to 2016 (retrospective period). The difference in failure proportion (noncompliance) of water samples for the four climatic seasons where statistically significant (p=0.004). A significant difference was observed between autumn and winter (p=0.003) and autumn and spring (p=0.025). The failure proportion of water samples for autumn was significantly higher (mean = 0.603231, sd = 0.19528237) compared to winter (mean = 0.316675, sd = 0.19649776) and spring (mean = 0.374495, sd = 0.20626332). No significant difference was observed for the failure proportion of water samples between the various years of the retrospective period xvi (p=0.416). Children under the age of five accounted for n=460 cases of diarrhoea with dehydration at the public health facilities for the retrospective period. The Kareedouw area (n=196) and Joubertina area (n=134) recorded the highest diarrhoeal cases reported for the study period. These two areas both had hospitals that operated 24 hours a day; however, the differences in cases reported between the two areas was not statistically significant (p=0.179). Diarrhoeal case data reported between the various years within the study period were significantly different (p<0.001). The observed differences were between 2012 and 2014 (p=0.008) and 2012 and 2015 (p=0.001). The differences in the cases of diarrhoea with dehydration, in children under five years of age, were not statistically significant for the four climatic seasons (p=0.121). The relationship between the failure proportion of water samples and the prevalence of diarrhoea with dehydration in children under five years of age was statistically significant (p=0.001). The results revealed a moderate positive relationship (rs=0.434) between the bacteriological quality of drinking water and the prevalence of cases of diarrhoea with dehydration. Water samples were collected at various sampling points for July 2017 and November 2018 and analysed for enteric pathogens. Vibrio cholerae, Salmonella sp. and Shigella sp. were detected in such water samples collected. The relationship between the failure proportion of water samples and the presence of enteric pathogens was not statistically significant (rs=0.56723, p=0.240). Conclusion: The overall bacteriological quality of drinking water within the municipality was poor and likely posed a potential health risk to consumers. The study further revealed a steep rise of diarrhoeal with dehydration prevalence in children under five years of age during 2013, which decreased slowly during the years to follow. A moderate, positive relationship existed between the failure proportion of water samples and diarrhoea with dehydration prevalence in children under five years of age (rs=0.434, p=0.001 ). Therefore, municipalities should improve their bulk water infrastructure and drinking water disinfecting methods while realising the need for increased awareness of water-borne disease prevention. , Thesis (MA) -- Faculty of Health Sciences, 2022
- Full Text:
- Date Issued: 2022-04
Water restriction and vitamin c supplementation on Xhosa goats during summer: Effect on growth performance, blood biochemical profile, nutrient balance, carcass characteristics and meat quality
- Akinmoladun, Oluwakamisi Festus https://orcid.org/0000-0001-6462-374X
- Authors: Akinmoladun, Oluwakamisi Festus https://orcid.org/0000-0001-6462-374X
- Date: 2020-08
- Subjects: Goats -- Nutrition , Goats -- Feeding and feeds
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/22710 , vital:52664
- Description: This study aimed to evaluate the effect of single and extra vitamin C (VC) supplementation on water-stressed Xhosa goats during the summer by evaluating their growth performance, blood biochemical profile, nutrient balance, carcass characteristics and meat qualities. The objectives were to assess the effect of water restriction and vitamin C supplementation by evaluating: firstly, growth performance, heat tolerance responses, and blood metabolites; secondly, intake, nutrient digestibility, nitrogen and mineral balance; thirdly, stress indices, carcass characteristics and meat qualities parameters and lastly, fatty acid profile, oxidative stability of lipids and sensory attributes were evaluated. To achieve these objectives, forty-two (42) goats were divided equally into seven treatments (75-day trial); without water restriction (W0, control); water restriction of 70percent of ad libitum water intake WI (W70); water restriction of 50percent ad libitum WI (W50); water restriction of 70percent of ad libitum WI plus 3g VC daily (W70+); water restriction 50percent of ad libitum WI plus 3g VC daily (W50+); water restriction of 70percent of ad libitumWI plus 3g VC and extra 5gVC given every eight-day (70++); water restriction of 50percent of ad libitum WI plus 3g VC and extra 5gVC given every eight-day (W50++). In the first objective, growth performance parameters, body condition scores, rectal temperature, respiratory rate, heat tolerance response parameters and blood metabolites were measured.Weight loss due to water restriction was reduced by VC supplementation in treated groups. The attenuation effect of VC was significant (P<0.05) in responses to respiratory rate (RR), Na+, K+, Mg2+, Cl-, Ca2+ and urea. Supplementation of VC (either single or multiple) did not (P>0.05) improve the effect of water restriction on body condition scores (BCs), FAMACHA©, glucose, globulin, alanine aminotransferase (ALT) and high-density lipoprotein (HDL). In the second objective, intake, nutrient digestibility, nitrogen and mineral balance were evaluated. The reduced nutrient intake was similar (P>0.05) irrespective of water restrictions and VC supplementations. Water-restriction levels did not affect nutrient intake/metabolic weight. Retained nitrogen increased with water-restriction levels but not influenced by VC. NH3-N decreased with the levels of water restriction while the pH was similar across the water restricted groups. Supplementation of VC had no effect (P>0.05) on apparent digestibility and digestible nutrients induced by water restriction levels. The amount of Ca, K, Mg retained increased (P<0.05) with water-restriction levels. In the third objective, stress indices, carcass characteristics and meat quality parameters were evaluated. The level of plasma cortisol concentration due to water stress was lessened (P<0.05) by VC. Follicle stimulating hormone (FSH), Luteinizing hormone (LH) and insulin were not affected (P>0.05) by levels of water restriction. The hot and carcass weights were lower (P<0.05) in W70+ and W50+ compared to W70 and W50 respectively. Vitamin C treated goats had higher redness (a*) compared to W70, W50 and W0. The shear force and cooking loss increased (P<0.05) with water restriction levels, while thaw loss, pH45min and pH24h were not affected by water restriction levels. In the final objective, the treatments did not affect (P>0.05) the oxidative stability of lipids (TBARS). The moisture and fat content in the water restricted groups were lower (P<0.05) than W0. The consumer meat sensory appearance decreased (P<0.05) with levels of water restrictions. Regardless of VC concentration and supplementation, vaccenic, and docosahexaenoic acid increased (P<0.05) while linolenic acid decreased as the water restriction levels increased. Nonetheless, treatment did not affect (P>0.05) the saturated and unsaturated fatty acids. These studies showed that suboptimal water intake negatively affects the growth performance and nutrient intake of Xhosa goats. However, the reduction in body weight loss and decreased plasma cortisol (chief stress hormone) concentration following vitamin C supplementation (especially at a daily single dose [3g/d]) may well reduce the effect of water stress in goats. , Thesis (PhD) -- Faculty of Science and Agriculture, 2020
- Full Text:
- Date Issued: 2020-08
- Authors: Akinmoladun, Oluwakamisi Festus https://orcid.org/0000-0001-6462-374X
- Date: 2020-08
- Subjects: Goats -- Nutrition , Goats -- Feeding and feeds
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/22710 , vital:52664
- Description: This study aimed to evaluate the effect of single and extra vitamin C (VC) supplementation on water-stressed Xhosa goats during the summer by evaluating their growth performance, blood biochemical profile, nutrient balance, carcass characteristics and meat qualities. The objectives were to assess the effect of water restriction and vitamin C supplementation by evaluating: firstly, growth performance, heat tolerance responses, and blood metabolites; secondly, intake, nutrient digestibility, nitrogen and mineral balance; thirdly, stress indices, carcass characteristics and meat qualities parameters and lastly, fatty acid profile, oxidative stability of lipids and sensory attributes were evaluated. To achieve these objectives, forty-two (42) goats were divided equally into seven treatments (75-day trial); without water restriction (W0, control); water restriction of 70percent of ad libitum water intake WI (W70); water restriction of 50percent ad libitum WI (W50); water restriction of 70percent of ad libitum WI plus 3g VC daily (W70+); water restriction 50percent of ad libitum WI plus 3g VC daily (W50+); water restriction of 70percent of ad libitumWI plus 3g VC and extra 5gVC given every eight-day (70++); water restriction of 50percent of ad libitum WI plus 3g VC and extra 5gVC given every eight-day (W50++). In the first objective, growth performance parameters, body condition scores, rectal temperature, respiratory rate, heat tolerance response parameters and blood metabolites were measured.Weight loss due to water restriction was reduced by VC supplementation in treated groups. The attenuation effect of VC was significant (P<0.05) in responses to respiratory rate (RR), Na+, K+, Mg2+, Cl-, Ca2+ and urea. Supplementation of VC (either single or multiple) did not (P>0.05) improve the effect of water restriction on body condition scores (BCs), FAMACHA©, glucose, globulin, alanine aminotransferase (ALT) and high-density lipoprotein (HDL). In the second objective, intake, nutrient digestibility, nitrogen and mineral balance were evaluated. The reduced nutrient intake was similar (P>0.05) irrespective of water restrictions and VC supplementations. Water-restriction levels did not affect nutrient intake/metabolic weight. Retained nitrogen increased with water-restriction levels but not influenced by VC. NH3-N decreased with the levels of water restriction while the pH was similar across the water restricted groups. Supplementation of VC had no effect (P>0.05) on apparent digestibility and digestible nutrients induced by water restriction levels. The amount of Ca, K, Mg retained increased (P<0.05) with water-restriction levels. In the third objective, stress indices, carcass characteristics and meat quality parameters were evaluated. The level of plasma cortisol concentration due to water stress was lessened (P<0.05) by VC. Follicle stimulating hormone (FSH), Luteinizing hormone (LH) and insulin were not affected (P>0.05) by levels of water restriction. The hot and carcass weights were lower (P<0.05) in W70+ and W50+ compared to W70 and W50 respectively. Vitamin C treated goats had higher redness (a*) compared to W70, W50 and W0. The shear force and cooking loss increased (P<0.05) with water restriction levels, while thaw loss, pH45min and pH24h were not affected by water restriction levels. In the final objective, the treatments did not affect (P>0.05) the oxidative stability of lipids (TBARS). The moisture and fat content in the water restricted groups were lower (P<0.05) than W0. The consumer meat sensory appearance decreased (P<0.05) with levels of water restrictions. Regardless of VC concentration and supplementation, vaccenic, and docosahexaenoic acid increased (P<0.05) while linolenic acid decreased as the water restriction levels increased. Nonetheless, treatment did not affect (P>0.05) the saturated and unsaturated fatty acids. These studies showed that suboptimal water intake negatively affects the growth performance and nutrient intake of Xhosa goats. However, the reduction in body weight loss and decreased plasma cortisol (chief stress hormone) concentration following vitamin C supplementation (especially at a daily single dose [3g/d]) may well reduce the effect of water stress in goats. , Thesis (PhD) -- Faculty of Science and Agriculture, 2020
- Full Text:
- Date Issued: 2020-08
Water Struggles and Rural People’s Experiences of Waiting in South Africa’s Eastern Cape Province
- Authors: Twalo, Lindani
- Date: 2021-10
- Subjects: Water security , Right to water
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/21201 , vital:47394
- Description: This study examined water struggles and rural people’s experiences of waiting in South Africa’s Eastern Cape Province. Primarily, it investigated how such struggles connect to people’s experiences of waiting for water services. In essence, the study demonstrates how experiences of waiting are profoundly shaped by subjective meanings that the rural people attach to water at a local level. Thus, the study connects rural water politics to contested meanings over natural resources in South Africa’s communal areas. The empirical analysis in this study goes beyond the largely urban focus in the focus in the politics of waiting – mainly in the informal settlements, slums and other urban peripheries. The study presents some of the less known struggles of rural dwellers, particularly their experiences of waiting for water service provision from the state. South Africa’s Constitution promotes the right to clean water. Despite all the progress made by the democratic government, it is still evident that people in deep rural areas of South Africa are in a very precarious situation when it comes to accessing clean water. The study utilised Auyero (2011) concept of the politics of waiting to examine the poor people’s experiences of waiting for water. The study adopted a case study of Lower Didimana village. The researcher conducted a range of qualitative research techniques – the key informant interviews, focus group discussions, observations and semi-structured interviews. The study found that rural residents of South Africa continue to wait for long periods for water service provision in the current democratic era. Moreover, they are still faced with severe challenges of accessing water; as a result, they are left with no better option but to use traditional ways of retrieving water. It also found that there are strong cultural and spiritual claims that rural dwellers attach to water. To them water is not just only a physiological need which could be addressed through efficient state service – the provision of sufficient tap water. Water is deeply connected in human existence. Just like land, water is a cultural as well as spiritual resource. As such, rural experiences of waiting are not limited to state agency and how the poor experience the state, but are also influences by local struggles over meanings of water. Finally, the study reveals the limitation in state policy on water provision, which is locked in a purely engineering use based paradigm, which mainly strives to address (technically) scarcity of drinking water. However, the findings of this study demonstrates that drinking is just one function of water. Although villagers try to mobilise to engage the state while waiting for water service they articulate other claims that connect to diverse water meanings. Such meanings are barely captured in contemporary literature on rural politics of water. As such, although water is increasing becoming scarce in rural South Africa and the state intervention is increasingly demanded, villagers’ experiences of waiting in Lower Didimana remain strongly connected to what water means to locals. , Thesis (MSoc Sci) (Rural Development) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-10
- Authors: Twalo, Lindani
- Date: 2021-10
- Subjects: Water security , Right to water
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/21201 , vital:47394
- Description: This study examined water struggles and rural people’s experiences of waiting in South Africa’s Eastern Cape Province. Primarily, it investigated how such struggles connect to people’s experiences of waiting for water services. In essence, the study demonstrates how experiences of waiting are profoundly shaped by subjective meanings that the rural people attach to water at a local level. Thus, the study connects rural water politics to contested meanings over natural resources in South Africa’s communal areas. The empirical analysis in this study goes beyond the largely urban focus in the focus in the politics of waiting – mainly in the informal settlements, slums and other urban peripheries. The study presents some of the less known struggles of rural dwellers, particularly their experiences of waiting for water service provision from the state. South Africa’s Constitution promotes the right to clean water. Despite all the progress made by the democratic government, it is still evident that people in deep rural areas of South Africa are in a very precarious situation when it comes to accessing clean water. The study utilised Auyero (2011) concept of the politics of waiting to examine the poor people’s experiences of waiting for water. The study adopted a case study of Lower Didimana village. The researcher conducted a range of qualitative research techniques – the key informant interviews, focus group discussions, observations and semi-structured interviews. The study found that rural residents of South Africa continue to wait for long periods for water service provision in the current democratic era. Moreover, they are still faced with severe challenges of accessing water; as a result, they are left with no better option but to use traditional ways of retrieving water. It also found that there are strong cultural and spiritual claims that rural dwellers attach to water. To them water is not just only a physiological need which could be addressed through efficient state service – the provision of sufficient tap water. Water is deeply connected in human existence. Just like land, water is a cultural as well as spiritual resource. As such, rural experiences of waiting are not limited to state agency and how the poor experience the state, but are also influences by local struggles over meanings of water. Finally, the study reveals the limitation in state policy on water provision, which is locked in a purely engineering use based paradigm, which mainly strives to address (technically) scarcity of drinking water. However, the findings of this study demonstrates that drinking is just one function of water. Although villagers try to mobilise to engage the state while waiting for water service they articulate other claims that connect to diverse water meanings. Such meanings are barely captured in contemporary literature on rural politics of water. As such, although water is increasing becoming scarce in rural South Africa and the state intervention is increasingly demanded, villagers’ experiences of waiting in Lower Didimana remain strongly connected to what water means to locals. , Thesis (MSoc Sci) (Rural Development) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-10