Africa‘s Heritage No. 2: Bantu religious beliefs
- Authors: Tracey, Hugh
- Subjects: Religion , Superstition , Evagenlising , Christianity , Arabs , Muhammadenism , Missionary , East Africa , Jesuit monks , Chopi , Marimba , Ethiopians , Conversion , Agnus Dei , The portuguese eat many things at the same time , The cow has leather to make shoes but the goat has no leather to make shoes , Eggs , Chicken , Portuguese eating habits , West Africa , Nigeria , Durban , Malaya , Housa , Soul , Spirit , Bantu , Philosophy , Sickness , Loss of soul , Possession , Casting out , Karanga , Confirmation , Children , Parental love , Mother , Parenting soul , Instinct , Dancing , Singing , Drum , Legends , Death , Legacy , Lake , Ghosts , Troph Zither , Haya , Evil spirits , Father Andre Fernandes , Father Dom Gonzalo de Silveira , Ngozi , Holy men , Divines , Chaminuka , Church , Church of Shembe , Christian dances , Worship , Emotive music , Rhythmic music , Gospel , Negro spiritual , Mass , Congo , Abenezaganbuia , Gombe zuco virato ambuzi capana virato , The Royal West African Frontier Force , The spirit of the lake , Moiritiri
- Language: English
- Type: Sound , Radio broadcast , Music
- Identifier: vital:15097 , http://hdl.handle.net/10962/d1008525 , Reel number: BC127
- Description: 2nd programme in the ‘Africa‘s Heritage Series, about Bantu religious beliefs, broadcast by the South African Broadcasting Corporation , For further details refer to the ILAM Document Collection: Hugh Tracey Broadcasts
- Full Text: false
- Authors: Tracey, Hugh
- Subjects: Religion , Superstition , Evagenlising , Christianity , Arabs , Muhammadenism , Missionary , East Africa , Jesuit monks , Chopi , Marimba , Ethiopians , Conversion , Agnus Dei , The portuguese eat many things at the same time , The cow has leather to make shoes but the goat has no leather to make shoes , Eggs , Chicken , Portuguese eating habits , West Africa , Nigeria , Durban , Malaya , Housa , Soul , Spirit , Bantu , Philosophy , Sickness , Loss of soul , Possession , Casting out , Karanga , Confirmation , Children , Parental love , Mother , Parenting soul , Instinct , Dancing , Singing , Drum , Legends , Death , Legacy , Lake , Ghosts , Troph Zither , Haya , Evil spirits , Father Andre Fernandes , Father Dom Gonzalo de Silveira , Ngozi , Holy men , Divines , Chaminuka , Church , Church of Shembe , Christian dances , Worship , Emotive music , Rhythmic music , Gospel , Negro spiritual , Mass , Congo , Abenezaganbuia , Gombe zuco virato ambuzi capana virato , The Royal West African Frontier Force , The spirit of the lake , Moiritiri
- Language: English
- Type: Sound , Radio broadcast , Music
- Identifier: vital:15097 , http://hdl.handle.net/10962/d1008525 , Reel number: BC127
- Description: 2nd programme in the ‘Africa‘s Heritage Series, about Bantu religious beliefs, broadcast by the South African Broadcasting Corporation , For further details refer to the ILAM Document Collection: Hugh Tracey Broadcasts
- Full Text: false
Shembe Christian Dances, Zulu Pilgrimage and Religious Convention
- Authors: Tracey, Hugh
- Subjects: January , Nhlangakazi Sacred Hill , Zulu Christians , Religious convention , Camps , Ndwedwe , Conviction , Shelter , Reeds , Sticks , Communion service , Dance , Zulu costumes , Pilgrimage , African intagibles , Folk stories , African negro music , American negro music , Arts , Pula , Tswana , Chief Batwe Village , Kanye , Lobatse , Bechuanaland , Portuguese missionaries , Jesuits , Father Dom Gonzalo de Silveira , Father Andre Fernandes , Chopi , Inyarime River , Henry VIII , Bantu religious songs , Rhodesia , Lake Victoria , Legend , Spirit of the Lake , Church , Hymn , Mbuluwundi, Reuben Tancard , Chingoma chakubaruka , Work songs , Hammers , Mbira , Nyoro , Modern spiritual , Shouting , Clapping , Club , Theatre , Uganda , Masindi
- Type: Sound , Radio broadcast , Music
- Identifier: vital:15131 , http://hdl.handle.net/10962/d1012130 , Reel number: BC155
- Description: Broadcast entitled 'Shembe Christian Dances, Zulu Pilgrimage and Religious Convention' broadcast by the South African Broadcasting Corporation , For further details refer to the ILAM Document Collection: Hugh Tracey Broadcasts
- Full Text: false
- Authors: Tracey, Hugh
- Subjects: January , Nhlangakazi Sacred Hill , Zulu Christians , Religious convention , Camps , Ndwedwe , Conviction , Shelter , Reeds , Sticks , Communion service , Dance , Zulu costumes , Pilgrimage , African intagibles , Folk stories , African negro music , American negro music , Arts , Pula , Tswana , Chief Batwe Village , Kanye , Lobatse , Bechuanaland , Portuguese missionaries , Jesuits , Father Dom Gonzalo de Silveira , Father Andre Fernandes , Chopi , Inyarime River , Henry VIII , Bantu religious songs , Rhodesia , Lake Victoria , Legend , Spirit of the Lake , Church , Hymn , Mbuluwundi, Reuben Tancard , Chingoma chakubaruka , Work songs , Hammers , Mbira , Nyoro , Modern spiritual , Shouting , Clapping , Club , Theatre , Uganda , Masindi
- Type: Sound , Radio broadcast , Music
- Identifier: vital:15131 , http://hdl.handle.net/10962/d1012130 , Reel number: BC155
- Description: Broadcast entitled 'Shembe Christian Dances, Zulu Pilgrimage and Religious Convention' broadcast by the South African Broadcasting Corporation , For further details refer to the ILAM Document Collection: Hugh Tracey Broadcasts
- Full Text: false
The Many Sides of African Music No. 8
- Authors: Tracey, Hugh , Mngoma, Khabi
- Subjects: Portuguese East Africa , Rock Oysters , Chopi , Bowmen , Cattle , Goats , Portuguese food , Komokomo , Story-telling , Flutes , Girls , Guitars , Zavala , Bazerutu , Xaixai , Villa Jean Bell , Chitingele , Zavala coast , Inharrime , Shangaan , Xylophones , Rubber headed beaters , Dom Gonzalo de Silvera , Missionaries , Andre Fernandez , Wedding , Jesuits , San Antonio , Timbila orchestra , Mzeno , Karingaro karingaan , Sol de Save , Gitonga language , Chief Nyakotowo , Ocarina , Matamba , Sikawele , Nightjar , Pigeon , Gelegele , Ndau , Ngonyana , Chibutu
- Language: English
- Type: Sound , Radio broadcast , Music
- Identifier: vital:15074 , http://hdl.handle.net/10962/d1008502 , Reel number: BC056
- Description: The Many Sides of African Music No. 8 of illustrated talks by Hugh Tracey and Peggy Tracey on their travels in search of African music, broadcast by the British Broadcasting Corporation , For further details refer to the ILAM Document Collection: Hugh Tracey Broadcasts
- Full Text: false
- Authors: Tracey, Hugh , Mngoma, Khabi
- Subjects: Portuguese East Africa , Rock Oysters , Chopi , Bowmen , Cattle , Goats , Portuguese food , Komokomo , Story-telling , Flutes , Girls , Guitars , Zavala , Bazerutu , Xaixai , Villa Jean Bell , Chitingele , Zavala coast , Inharrime , Shangaan , Xylophones , Rubber headed beaters , Dom Gonzalo de Silvera , Missionaries , Andre Fernandez , Wedding , Jesuits , San Antonio , Timbila orchestra , Mzeno , Karingaro karingaan , Sol de Save , Gitonga language , Chief Nyakotowo , Ocarina , Matamba , Sikawele , Nightjar , Pigeon , Gelegele , Ndau , Ngonyana , Chibutu
- Language: English
- Type: Sound , Radio broadcast , Music
- Identifier: vital:15074 , http://hdl.handle.net/10962/d1008502 , Reel number: BC056
- Description: The Many Sides of African Music No. 8 of illustrated talks by Hugh Tracey and Peggy Tracey on their travels in search of African music, broadcast by the British Broadcasting Corporation , For further details refer to the ILAM Document Collection: Hugh Tracey Broadcasts
- Full Text: false
Disgrace as J.M.Coetzee's Tempest
- Authors: Wright, Laurence
- Date: 2008
- Language: English
- Type: Book chapter
- Identifier: vital:7030 , http://hdl.handle.net/10962/d1007217
- Description: Amid the deluge of criticism and commentary evoked by Disgrace, quite remarkably nobody has noticed that the book re-engages exactly the energies Shakespeare deployed in The Tempest, a play which has become an icon, if not the icon, of colonial and post-colonial studies.
- Full Text:
- Date Issued: 2008
- Authors: Wright, Laurence
- Date: 2008
- Language: English
- Type: Book chapter
- Identifier: vital:7030 , http://hdl.handle.net/10962/d1007217
- Description: Amid the deluge of criticism and commentary evoked by Disgrace, quite remarkably nobody has noticed that the book re-engages exactly the energies Shakespeare deployed in The Tempest, a play which has become an icon, if not the icon, of colonial and post-colonial studies.
- Full Text:
- Date Issued: 2008
Lag length selection for vector error correction models
- Authors: Sharp, Gary David
- Date: 2010
- Subjects: Akaike Information Criterion Mathematical models -- Evaluation Autoregression (Statistics) Error analysis (Mathematics)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5568 , http://hdl.handle.net/10962/d1002808
- Description: This thesis investigates the problem of model identification in a Vector Autoregressive framework. The study reviews the existing research, conducts an extensive simulation based analysis of thirteen information theoretic criterion (IC), one of which is a novel derivation. The simulation exercise considers the evaluation of seven alternative error restricted vector autoregressive models with four different lag lengths. Alternative sample sizes and parameterisations are also evaluated and compared to results in the existing literature. The results of the comparative analysis provide strong support for the efficiency based criterion of Akaike and in particular the selection capability of the novel criterion, referred to as a modified corrected Akaike information criterion, demonstrates useful finite sample properties.
- Full Text:
- Date Issued: 2010
- Authors: Sharp, Gary David
- Date: 2010
- Subjects: Akaike Information Criterion Mathematical models -- Evaluation Autoregression (Statistics) Error analysis (Mathematics)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5568 , http://hdl.handle.net/10962/d1002808
- Description: This thesis investigates the problem of model identification in a Vector Autoregressive framework. The study reviews the existing research, conducts an extensive simulation based analysis of thirteen information theoretic criterion (IC), one of which is a novel derivation. The simulation exercise considers the evaluation of seven alternative error restricted vector autoregressive models with four different lag lengths. Alternative sample sizes and parameterisations are also evaluated and compared to results in the existing literature. The results of the comparative analysis provide strong support for the efficiency based criterion of Akaike and in particular the selection capability of the novel criterion, referred to as a modified corrected Akaike information criterion, demonstrates useful finite sample properties.
- Full Text:
- Date Issued: 2010
Irony and transcendence on the Renaissance stage
- Authors: Wright, Laurence
- Date: 2004
- Language: English
- Type: text , article
- Identifier: vital:7067 , http://hdl.handle.net/10962/d1007455 , https://doi.org/10.1484/M.CURSOR-EB.3.4728
- Description: preprint , This is the concluding essay in a collection entitled 'This Earthly Stage'. The chapter argues that the peculiar task of the stage metaphor - the notion of the theatre as a metaphor for life,which involves complex interactions between rarefied intellectual constructions of life and mundane reality - is to interrogate the tension between an inscrutable cosmic order and the limited viewpoints of ordinary humanity.The piece moves from general considerations of irony and dramatic irony, via an analysis of Kyd's The Spanish Tragedy, to comments on Petrarch, Pico and Vives, culminating in a consideration of irony and transcendence in Shakespeare's last plays.
- Full Text:
- Date Issued: 2004
- Authors: Wright, Laurence
- Date: 2004
- Language: English
- Type: text , article
- Identifier: vital:7067 , http://hdl.handle.net/10962/d1007455 , https://doi.org/10.1484/M.CURSOR-EB.3.4728
- Description: preprint , This is the concluding essay in a collection entitled 'This Earthly Stage'. The chapter argues that the peculiar task of the stage metaphor - the notion of the theatre as a metaphor for life,which involves complex interactions between rarefied intellectual constructions of life and mundane reality - is to interrogate the tension between an inscrutable cosmic order and the limited viewpoints of ordinary humanity.The piece moves from general considerations of irony and dramatic irony, via an analysis of Kyd's The Spanish Tragedy, to comments on Petrarch, Pico and Vives, culminating in a consideration of irony and transcendence in Shakespeare's last plays.
- Full Text:
- Date Issued: 2004
Consistent testing for lag length in cointegrated relationships
- Authors: Liu, Limin
- Date: 2007
- Subjects: Cointegration -- South Africa , Econometrics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10575 , http://hdl.handle.net/10948/547 , http://hdl.handle.net/10948/d1011715 , Cointegration -- South Africa , Econometrics
- Description: In the past few decades the theory of cointegration has been widely used in the empirical analysis of economic data. The reason is that, it captures the economic notion of a long-run economic relation. One of the problems experienced when applying cointegrated techniques to econometric modelling is the determination of lag lengths for the modelled variables. Applied studies have resulted in contradictory choices for lag length selection. This study reviews and compares some of the well-known information criteria using simulation techniques for bivariate models.
- Full Text:
- Date Issued: 2007
- Authors: Liu, Limin
- Date: 2007
- Subjects: Cointegration -- South Africa , Econometrics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10575 , http://hdl.handle.net/10948/547 , http://hdl.handle.net/10948/d1011715 , Cointegration -- South Africa , Econometrics
- Description: In the past few decades the theory of cointegration has been widely used in the empirical analysis of economic data. The reason is that, it captures the economic notion of a long-run economic relation. One of the problems experienced when applying cointegrated techniques to econometric modelling is the determination of lag lengths for the modelled variables. Applied studies have resulted in contradictory choices for lag length selection. This study reviews and compares some of the well-known information criteria using simulation techniques for bivariate models.
- Full Text:
- Date Issued: 2007
Model selection for cointegrated relationships in small samples
- He, Wei
- Authors: He, Wei
- Date: 2008
- Subjects: Economics -- Statistical methods , Cointegration -- South Africa , Econometrics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10570 , http://hdl.handle.net/10948/971 , Economics -- Statistical methods , Cointegration -- South Africa , Econometrics
- Description: Vector autoregression models have become widely used research tools in the analysis of macroeconomic time series. Cointegrated techniques are an essential part of empirical macroeconomic research. They infer causal long-run relationships between nonstationary variables. In this study, six information criteria were reviewed and compared. The methods focused on determining the optimum information criteria for detecting the correct lag structure of a two-variable cointegrated process.
- Full Text:
- Date Issued: 2008
- Authors: He, Wei
- Date: 2008
- Subjects: Economics -- Statistical methods , Cointegration -- South Africa , Econometrics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10570 , http://hdl.handle.net/10948/971 , Economics -- Statistical methods , Cointegration -- South Africa , Econometrics
- Description: Vector autoregression models have become widely used research tools in the analysis of macroeconomic time series. Cointegrated techniques are an essential part of empirical macroeconomic research. They infer causal long-run relationships between nonstationary variables. In this study, six information criteria were reviewed and compared. The methods focused on determining the optimum information criteria for detecting the correct lag structure of a two-variable cointegrated process.
- Full Text:
- Date Issued: 2008
Characterization of phthalocyanine functionalized quantum dots by dynamic light scattering, laser Doppler, and capillary electrophoresis
- Ramírez-García, Gonzalo, Oluwole, David O, Nxele, Siphesihle Robin, d’Orlyé, Fanny, Nyokong, Tebello, Bedioui, Fethi, Varenne, Anne
- Authors: Ramírez-García, Gonzalo , Oluwole, David O , Nxele, Siphesihle Robin , d’Orlyé, Fanny , Nyokong, Tebello , Bedioui, Fethi , Varenne, Anne
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/238184 , vital:50595 , xlink:href="https://doi.org/10.1007/s00216-016-0120-x"
- Description: In this work, we characterized different phtalocyanine-capped core/shell/shell quantum dots (QDs) in terms of stability, ζ-potential, and size at various pH and ionic strengths, by means of capillary electrophoresis (CE), and compared these results to the ones obtained by laser Doppler electrophoresis (LDE) and dynamic light scattering (DLS). The effect of the phthalocyanine metallic center (Zn, Al, or In), the number (one or four), and nature of substituents (carboxyphenoxy- or sulfonated-) of functionalization on the phthalocyanine physicochemical properties were evaluated. Whereas QDs capped with zinc mono-carboxyphenoxy-phtalocyanine (ZnMCPPc-QDs) remained aggregated in the whole analyzed pH range, even at low ionic strength, QDs capped with zinc tetracarboxyphenoxy phtalocyanine (ZnTPPc-QDs) were easily dispersed in buffers at pH equal to or higher than 7.4. QDs capped with aluminum tetrasulfonated phthalocyanine (AlTSPPc-QDs) and indium tetracarboxyphenoxy phthalocyanines (InTCPPc-QDs) were stable in aqueous suspension only at pH higher than 9.0 due to the presence of functional groups bound to the metallic center of the phthalocyanine. The ζ-potential values determined by CE for all the samples decreased when ionic strength increased, being well correlated with the aggregation of the nanoconjugates at elevated salt concentrations. The use of electrokinetic methodologies has provided insights into the colloidal stability of the photosensitizer-functionalized QDs in physiological relevant solutions and thereby, its usefulness for improving their design and applications for photodynamic therapy.
- Full Text:
- Date Issued: 2017
- Authors: Ramírez-García, Gonzalo , Oluwole, David O , Nxele, Siphesihle Robin , d’Orlyé, Fanny , Nyokong, Tebello , Bedioui, Fethi , Varenne, Anne
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/238184 , vital:50595 , xlink:href="https://doi.org/10.1007/s00216-016-0120-x"
- Description: In this work, we characterized different phtalocyanine-capped core/shell/shell quantum dots (QDs) in terms of stability, ζ-potential, and size at various pH and ionic strengths, by means of capillary electrophoresis (CE), and compared these results to the ones obtained by laser Doppler electrophoresis (LDE) and dynamic light scattering (DLS). The effect of the phthalocyanine metallic center (Zn, Al, or In), the number (one or four), and nature of substituents (carboxyphenoxy- or sulfonated-) of functionalization on the phthalocyanine physicochemical properties were evaluated. Whereas QDs capped with zinc mono-carboxyphenoxy-phtalocyanine (ZnMCPPc-QDs) remained aggregated in the whole analyzed pH range, even at low ionic strength, QDs capped with zinc tetracarboxyphenoxy phtalocyanine (ZnTPPc-QDs) were easily dispersed in buffers at pH equal to or higher than 7.4. QDs capped with aluminum tetrasulfonated phthalocyanine (AlTSPPc-QDs) and indium tetracarboxyphenoxy phthalocyanines (InTCPPc-QDs) were stable in aqueous suspension only at pH higher than 9.0 due to the presence of functional groups bound to the metallic center of the phthalocyanine. The ζ-potential values determined by CE for all the samples decreased when ionic strength increased, being well correlated with the aggregation of the nanoconjugates at elevated salt concentrations. The use of electrokinetic methodologies has provided insights into the colloidal stability of the photosensitizer-functionalized QDs in physiological relevant solutions and thereby, its usefulness for improving their design and applications for photodynamic therapy.
- Full Text:
- Date Issued: 2017
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
Development of molecularly imprinted polymer based solid phase extraction sorbents for the selective cleanup of food and pharmaceutical residue samples
- Authors: Batlokwa, Bareki Shima
- Date: 2012
- Subjects: Sorbents -- Research Nanofibers -- Research Aflatoxins -- Research Electrospinning -- Research Extraction (Chemistry) -- Research
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4309 , http://hdl.handle.net/10962/d1004967
- Description: This thesis presents the development of chlorophyll, cholic acid, aflatoxin B1 molecularly imprinted polymer (MIP) particles and cholic acid MIP nanofibers for application as selective solid phase extraction (SPE) sorbents. The particles were prepared by bulk polymerization and the nanofibers by a novel approach combining molecular imprinting and electrospinning technology. The AFB1 MIP particles were compared with an aflatoxin specific immunoextraction sorbent in cleaning-up and pre-concentrating aflatoxins from nut extracts. They both recorded high extraction efficiencies (EEs) of > 97 % in selectively extracting the aflatoxins (AFB1, AFB2, AFG1 and AFG2). High reproducibility marked by the low %RSDs of < 1% and low LODs of ≤ 0.02 ng/g were calculated in all cases. The LODs were within the monitoring requirements of the European Commission. The results were validated with a peanut butter certified reference material. The chlorophyll MIP on the other hand selectively removed chlorophyll that would otherwise interfere during pesticide residue analysis (PRA) from > 0.6 to <0.09 Au in green plants extracts. The extracted chlorophyll was removed to far below the level of ≥ 0.399 Au that is usually associated with interference during PRA. Furthermore, the MIP demonstrated better selectivity by removing only chlorophyll (> 99%) in the presence of planar pesticides than the currently employed graphitized carbon black (GCB) that removed both the chlorophyll (> 88%) and planar pesticides (> 89%). For the interfering cholic acid during drug residue analysis, cholic acid MIP electrospun nanofibers demonstrated to be more sensitive and possessing higher loading capacity than the MIP particles. 100% cholic acid was removed by the nanofibers from standard solutions relative to 80% by the particles. This showed that the nanofibers have better performance than the micro particles and as such have potential to replace the particle based SPE sorbents that are currently in use. All the templates were optimally removed from the prepared MIPs by employing a novel pressurized hot water extraction template removal method that was used for the first time in this thesis. The method employed only water, an environmentally friendly solvent to remove templates to ≥ 99.6% with template residual bleeding of ≤ 0.02%.
- Full Text:
- Date Issued: 2012
- Authors: Batlokwa, Bareki Shima
- Date: 2012
- Subjects: Sorbents -- Research Nanofibers -- Research Aflatoxins -- Research Electrospinning -- Research Extraction (Chemistry) -- Research
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4309 , http://hdl.handle.net/10962/d1004967
- Description: This thesis presents the development of chlorophyll, cholic acid, aflatoxin B1 molecularly imprinted polymer (MIP) particles and cholic acid MIP nanofibers for application as selective solid phase extraction (SPE) sorbents. The particles were prepared by bulk polymerization and the nanofibers by a novel approach combining molecular imprinting and electrospinning technology. The AFB1 MIP particles were compared with an aflatoxin specific immunoextraction sorbent in cleaning-up and pre-concentrating aflatoxins from nut extracts. They both recorded high extraction efficiencies (EEs) of > 97 % in selectively extracting the aflatoxins (AFB1, AFB2, AFG1 and AFG2). High reproducibility marked by the low %RSDs of < 1% and low LODs of ≤ 0.02 ng/g were calculated in all cases. The LODs were within the monitoring requirements of the European Commission. The results were validated with a peanut butter certified reference material. The chlorophyll MIP on the other hand selectively removed chlorophyll that would otherwise interfere during pesticide residue analysis (PRA) from > 0.6 to <0.09 Au in green plants extracts. The extracted chlorophyll was removed to far below the level of ≥ 0.399 Au that is usually associated with interference during PRA. Furthermore, the MIP demonstrated better selectivity by removing only chlorophyll (> 99%) in the presence of planar pesticides than the currently employed graphitized carbon black (GCB) that removed both the chlorophyll (> 88%) and planar pesticides (> 89%). For the interfering cholic acid during drug residue analysis, cholic acid MIP electrospun nanofibers demonstrated to be more sensitive and possessing higher loading capacity than the MIP particles. 100% cholic acid was removed by the nanofibers from standard solutions relative to 80% by the particles. This showed that the nanofibers have better performance than the micro particles and as such have potential to replace the particle based SPE sorbents that are currently in use. All the templates were optimally removed from the prepared MIPs by employing a novel pressurized hot water extraction template removal method that was used for the first time in this thesis. The method employed only water, an environmentally friendly solvent to remove templates to ≥ 99.6% with template residual bleeding of ≤ 0.02%.
- Full Text:
- Date Issued: 2012
An investigation into the effect of military influences on the theology and form of The Spiritual Exercise of Ignatius of Loyola
- Authors: Christie, David Osborne
- Date: 1999
- Subjects: Ignatius, of Loyola, Saint, 1491-1556. Exercitia spiritualia
- Language: English
- Type: Thesis , Masters , MTh
- Identifier: vital:1241 , http://hdl.handle.net/10962/d1008540
- Description: The purpose of this thesis is to investigate the influences of a military nature affecting the life of Ignatius of Loyola up to the time he wrote The Spiritual Exercises, and to assess whether such influences may have affected the theology and form of The Spiritual Exercises. The investigation opens with an apologetic on why the author considers it desirable to examine The Spiritual Exercises from this point of view. Thereafter a review of the life of Ignatius up to the time he wrote The Exercises is undertaken to identify which sources may have provided influences of a military nature or nuance, and to examine what possible effect these had upon Ignatius. The potential sources of influence examined include Ignatius's family background and the milieu in which he grew up, the attitude of his mentors in particular and society in general to the profession of arms, and Ignatius's own response to this attitude. From the age of twenty-five to thirty Ignatius was employed on duties of a principally military nature until he was severely wounded at the Battle of Pamplona in 1521. Therefore his military experience is examined together with an attempt to assess the degree, if any, of his spirituality at that point in his life. This is followed by an investigation of the literary sources available to Ignatius from the time of his wounding up to the time when he wrote The Spiritual Exercises at Manresa. Thereafter an examination of the changes which took place in his psyche and spirit, from the time he was wounded up to the time he wrote The Spiritual Exercises is undertaken, in order to ascertain whether his attitude to military concepts immediately prior to writing The Exercises had changed from his pre-Pamplona days. The Spiritual Exercises are then examined to consider which portions, if any, were affected in form or theology by military influences or nuances. The conclusion reached is that whereas The Spiritual Exercises are in no way a military treatise, the form is affected to a reasonable degree by Ignatius's experiences of, and attitude to, the military life, whereas the theology is affected only slightly.
- Full Text:
- Date Issued: 1999
- Authors: Christie, David Osborne
- Date: 1999
- Subjects: Ignatius, of Loyola, Saint, 1491-1556. Exercitia spiritualia
- Language: English
- Type: Thesis , Masters , MTh
- Identifier: vital:1241 , http://hdl.handle.net/10962/d1008540
- Description: The purpose of this thesis is to investigate the influences of a military nature affecting the life of Ignatius of Loyola up to the time he wrote The Spiritual Exercises, and to assess whether such influences may have affected the theology and form of The Spiritual Exercises. The investigation opens with an apologetic on why the author considers it desirable to examine The Spiritual Exercises from this point of view. Thereafter a review of the life of Ignatius up to the time he wrote The Exercises is undertaken to identify which sources may have provided influences of a military nature or nuance, and to examine what possible effect these had upon Ignatius. The potential sources of influence examined include Ignatius's family background and the milieu in which he grew up, the attitude of his mentors in particular and society in general to the profession of arms, and Ignatius's own response to this attitude. From the age of twenty-five to thirty Ignatius was employed on duties of a principally military nature until he was severely wounded at the Battle of Pamplona in 1521. Therefore his military experience is examined together with an attempt to assess the degree, if any, of his spirituality at that point in his life. This is followed by an investigation of the literary sources available to Ignatius from the time of his wounding up to the time when he wrote The Spiritual Exercises at Manresa. Thereafter an examination of the changes which took place in his psyche and spirit, from the time he was wounded up to the time he wrote The Spiritual Exercises is undertaken, in order to ascertain whether his attitude to military concepts immediately prior to writing The Exercises had changed from his pre-Pamplona days. The Spiritual Exercises are then examined to consider which portions, if any, were affected in form or theology by military influences or nuances. The conclusion reached is that whereas The Spiritual Exercises are in no way a military treatise, the form is affected to a reasonable degree by Ignatius's experiences of, and attitude to, the military life, whereas the theology is affected only slightly.
- Full Text:
- Date Issued: 1999
Production and molecular characterization of peroxidases from novel ligninolytic proteobacteria and bacillus strains
- Authors: Falade, Ayodeji Osmund
- Date: 2018
- Subjects: Peroxidase Catalase
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/9702 , vital:34823
- Description: Inadequate quantity is a major impediment to the industrial application of peroxidase and other industrial enzymes. Consequently, efforts are geared towards increasing peroxidase production by searching for new microbes with enhanced production capacity. In this study, three novel ligninolytic bacteria: Raoultella ornithinolytica OKOH-1 (KX640917), Ensifer adhaerens NWODO-2 (KX640918) and Bacillus sp. FALADE-1 (KX640922) were optimized for peroxidase production and their peroxidases characterized using molecular and biochemical approaches. Molecular analysis confirmed the presence of peroxidase genes in the three bacteria. BLAST result and phylogenetic analysis of the deduced amino acid sequences suggested that Raoultella ornithinolytica OKOH-1 peroxidase (RaoPrx) belongs to a DyP-type peroxidase family while peroxidases from Ensifer adhaerens NWODO-2 and Bacillus sp. FALADE-1 are catalase-peroxidases. The peroxidase genes are available in the GenBank with MF370527, MF374336 and MF407314 as respective accession numbers. Upon optimization, Raoultella ornithinolytica OKOH-1 exhibited the highest peroxidase production at pH 5, 35 oC and 150 rpm. Biochemical characterization showed that RaoPrx had a wide substrate specificity as it was able to oxidize all the tested substrates in this study (ABTS, veratryl alcohol, guaiacol and pyrogallol), except 2, 6-Dimethoxyphenol. However, highest activity by the enzyme was recorded with pyrogallol as substrate. The enzyme had an optimum activity at pH 6 and 50 oC and was very stable at high temperatures (50 oC – 70 oC). Its pH stability was over a pH range of 5.0 – 7.0. Moreover, RaoPrx activity was significantly enhanced by Ag+, Cu2+, Zn2+and Fe2+ while Ca2+, Mg2+, Ba2+, Al3+, Co2+, NaN3 and EDTA inhibited the activity of the enzyme. Nevertheless, RaoPrx exhibited a remarkable dye-decolourizing activity on congo red and melanin, indicating the biotechnological potential of the enzyme in dye decolourization and development of cosmetic agent. Generally, the results from this study suggest that ligninolytic bacteria hold a great potential for enhanced peroxidase production that could meet the increasing industrial demand.
- Full Text:
- Date Issued: 2018
- Authors: Falade, Ayodeji Osmund
- Date: 2018
- Subjects: Peroxidase Catalase
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/9702 , vital:34823
- Description: Inadequate quantity is a major impediment to the industrial application of peroxidase and other industrial enzymes. Consequently, efforts are geared towards increasing peroxidase production by searching for new microbes with enhanced production capacity. In this study, three novel ligninolytic bacteria: Raoultella ornithinolytica OKOH-1 (KX640917), Ensifer adhaerens NWODO-2 (KX640918) and Bacillus sp. FALADE-1 (KX640922) were optimized for peroxidase production and their peroxidases characterized using molecular and biochemical approaches. Molecular analysis confirmed the presence of peroxidase genes in the three bacteria. BLAST result and phylogenetic analysis of the deduced amino acid sequences suggested that Raoultella ornithinolytica OKOH-1 peroxidase (RaoPrx) belongs to a DyP-type peroxidase family while peroxidases from Ensifer adhaerens NWODO-2 and Bacillus sp. FALADE-1 are catalase-peroxidases. The peroxidase genes are available in the GenBank with MF370527, MF374336 and MF407314 as respective accession numbers. Upon optimization, Raoultella ornithinolytica OKOH-1 exhibited the highest peroxidase production at pH 5, 35 oC and 150 rpm. Biochemical characterization showed that RaoPrx had a wide substrate specificity as it was able to oxidize all the tested substrates in this study (ABTS, veratryl alcohol, guaiacol and pyrogallol), except 2, 6-Dimethoxyphenol. However, highest activity by the enzyme was recorded with pyrogallol as substrate. The enzyme had an optimum activity at pH 6 and 50 oC and was very stable at high temperatures (50 oC – 70 oC). Its pH stability was over a pH range of 5.0 – 7.0. Moreover, RaoPrx activity was significantly enhanced by Ag+, Cu2+, Zn2+and Fe2+ while Ca2+, Mg2+, Ba2+, Al3+, Co2+, NaN3 and EDTA inhibited the activity of the enzyme. Nevertheless, RaoPrx exhibited a remarkable dye-decolourizing activity on congo red and melanin, indicating the biotechnological potential of the enzyme in dye decolourization and development of cosmetic agent. Generally, the results from this study suggest that ligninolytic bacteria hold a great potential for enhanced peroxidase production that could meet the increasing industrial demand.
- Full Text:
- Date Issued: 2018
The relationship between interest rates and inflation in South Africa : revisiting Fisher's hypothesis
- Mitchell-Innes, Henry Alexander
- Authors: Mitchell-Innes, Henry Alexander
- Date: 2006
- Subjects: Fisher effect (Economics) , Interest rates -- South Africa , Interest rates -- Effect of inflation -- South Africa , Inflation (Finance) -- South Africa , Monetary policy -- South Africa , Banks and banking, Central -- South Africa , South Africa -- Economic conditions
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:991 , http://hdl.handle.net/10962/d1002726 , Fisher effect (Economics) , Interest rates -- South Africa , Interest rates -- Effect of inflation -- South Africa , Inflation (Finance) -- South Africa , Monetary policy -- South Africa , Banks and banking, Central -- South Africa , South Africa -- Economic conditions
- Description: This thesis investigates the relationship between expected inflation and nominal interest rates in South Africa and the extent to which the Fisher effect hypothesis holds. The hypothesis, proposed by Fisher (1930), that the nominal rate of interest should reflect movements in the expected rate of inflation has been the subject of much empirical research in many industrialised countries. This wealth of literature can be attributed to various factors including the pivotal role that the nominal rate of interest and, perhaps more importantly, the real rate of interest plays in the economy. The validity of the Fisher effect also has important implications for monetary policy and needs to be considered by central banks. Few studies have been conducted in South Africa to validate this important hypothesis. The analysis uses the 3-month bankers’ acceptance rate and the 10-year government bond rate to proxy both short- and long-term interest rates. The existence of a long-run unit proportional relationship between nominal interest rates and expected inflation is tested using Johansen’s cointegration test. The data is analysed for the period April 2000 to July 2005 as the research aims to establish whether the Fisher relationship holds within an inflation targeting monetary policy framework. The short-run Fisher effect is not empirically verified. This is due to the effects of the monetary policy transmission mechanism and implies that short-term nominal interest rates are a good indication of the stance of monetary policy. A long-run cointegrating relationship is established between long-term interest rates and expected inflation. The long-run adjustment is less than unity, which can be attributed to the credibility of the inflation-targeting framework.
- Full Text:
- Date Issued: 2006
- Authors: Mitchell-Innes, Henry Alexander
- Date: 2006
- Subjects: Fisher effect (Economics) , Interest rates -- South Africa , Interest rates -- Effect of inflation -- South Africa , Inflation (Finance) -- South Africa , Monetary policy -- South Africa , Banks and banking, Central -- South Africa , South Africa -- Economic conditions
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:991 , http://hdl.handle.net/10962/d1002726 , Fisher effect (Economics) , Interest rates -- South Africa , Interest rates -- Effect of inflation -- South Africa , Inflation (Finance) -- South Africa , Monetary policy -- South Africa , Banks and banking, Central -- South Africa , South Africa -- Economic conditions
- Description: This thesis investigates the relationship between expected inflation and nominal interest rates in South Africa and the extent to which the Fisher effect hypothesis holds. The hypothesis, proposed by Fisher (1930), that the nominal rate of interest should reflect movements in the expected rate of inflation has been the subject of much empirical research in many industrialised countries. This wealth of literature can be attributed to various factors including the pivotal role that the nominal rate of interest and, perhaps more importantly, the real rate of interest plays in the economy. The validity of the Fisher effect also has important implications for monetary policy and needs to be considered by central banks. Few studies have been conducted in South Africa to validate this important hypothesis. The analysis uses the 3-month bankers’ acceptance rate and the 10-year government bond rate to proxy both short- and long-term interest rates. The existence of a long-run unit proportional relationship between nominal interest rates and expected inflation is tested using Johansen’s cointegration test. The data is analysed for the period April 2000 to July 2005 as the research aims to establish whether the Fisher relationship holds within an inflation targeting monetary policy framework. The short-run Fisher effect is not empirically verified. This is due to the effects of the monetary policy transmission mechanism and implies that short-term nominal interest rates are a good indication of the stance of monetary policy. A long-run cointegrating relationship is established between long-term interest rates and expected inflation. The long-run adjustment is less than unity, which can be attributed to the credibility of the inflation-targeting framework.
- Full Text:
- Date Issued: 2006
Stability of the money demand function and monetary inflation in the East African community
- Authors: Nsabimana, Adelit
- Date: 2015
- Subjects: Monetary policy -- Africa, East , Inflation (Finance) -- Africa, East , Equilibrium (Economics)
- Language: English
- Type: Thesis , Doctoral , DCom
- Identifier: http://hdl.handle.net/10948/9163 , vital:26470
- Description: This research attempts to evaluate the stability of money demand functions and estimate monetary inflation models in the East African Community (EAC), using quarterly aggregate data that range from 2000Q1 to 2012Q3. We used Johansen co-integration analysis to estimate and analyse the stability of the M3 money demand model for each country member of the EAC. From this estimation, we derived a country-specific measure of money overhang. We compared its forecasting power of future inflation with that of money stock growth, and money stock available in the economy. Regarding country-specific money demand functions, with the exception of Uganda, we identified a reasonable and stable country-specific M3 money demand model. Also, for predicting future inflation, the estimation results showed that M3 money stock growth is more reliable in Burundi and in Kenya, while M3 money overhang is preferable in Rwanda and M3 money stock in Tanzania. As both country-specific and regional (EAC area) information on monetary quantity growth and its impact on price level is important to know in a monetary union, we considered the EAC area as a single market and attempted to estimate the aggregate (EAC area) demand functions for broad money M2 and M3 using Johansen co-integration analysis. The estimated long-run aggregate money demand models M2 and M3 appeared to be stable over the sample period. However, the aggregate M2 and M3 at the EAC level were proven to be weakly exogenous, which should discard them for consideration at the EAC level as the intermediate targets variables in order to achieve the overall objective of price stability in the EAC region. Instead, short-term interest rate should be given a prominent role in monetary policy framework at the EAC level.
- Full Text:
- Date Issued: 2015
- Authors: Nsabimana, Adelit
- Date: 2015
- Subjects: Monetary policy -- Africa, East , Inflation (Finance) -- Africa, East , Equilibrium (Economics)
- Language: English
- Type: Thesis , Doctoral , DCom
- Identifier: http://hdl.handle.net/10948/9163 , vital:26470
- Description: This research attempts to evaluate the stability of money demand functions and estimate monetary inflation models in the East African Community (EAC), using quarterly aggregate data that range from 2000Q1 to 2012Q3. We used Johansen co-integration analysis to estimate and analyse the stability of the M3 money demand model for each country member of the EAC. From this estimation, we derived a country-specific measure of money overhang. We compared its forecasting power of future inflation with that of money stock growth, and money stock available in the economy. Regarding country-specific money demand functions, with the exception of Uganda, we identified a reasonable and stable country-specific M3 money demand model. Also, for predicting future inflation, the estimation results showed that M3 money stock growth is more reliable in Burundi and in Kenya, while M3 money overhang is preferable in Rwanda and M3 money stock in Tanzania. As both country-specific and regional (EAC area) information on monetary quantity growth and its impact on price level is important to know in a monetary union, we considered the EAC area as a single market and attempted to estimate the aggregate (EAC area) demand functions for broad money M2 and M3 using Johansen co-integration analysis. The estimated long-run aggregate money demand models M2 and M3 appeared to be stable over the sample period. However, the aggregate M2 and M3 at the EAC level were proven to be weakly exogenous, which should discard them for consideration at the EAC level as the intermediate targets variables in order to achieve the overall objective of price stability in the EAC region. Instead, short-term interest rate should be given a prominent role in monetary policy framework at the EAC level.
- Full Text:
- Date Issued: 2015
Preparation and use of maize tassels’ activated carbon for the adsorption of phenolic compounds in environmental waste water samples
- Olorundare, O F, Msagati, T A M, Okonkwo, J O, Krause, Rui W M, Mamba, Bhekie B
- Authors: Olorundare, O F , Msagati, T A M , Okonkwo, J O , Krause, Rui W M , Mamba, Bhekie B
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125331 , vital:35773 , https://doi.org/10.1007/s11356-014-3742-6
- Description: The determination and remediation of three phenolic compounds bisphenol A (BPA), ortho-nitrophenol (o-NTP), parachlorophenol (PCP) in wastewater is reported. The analysis of these molecules in wastewater was done using gas chromatography (GC) × GC time-of-flight mass spectrometry while activated carbon derived from maize tassel was used as an adsorbent. During the experimental procedures, the effect of various parameters such as initial concentration, pH of sample solution, eluent volume, and sample volume on the removal efficiency with respect to the three phenolic compounds was studied. The results showed that maize tassel produced activated carbon (MTAC) cartridge packed solid-phase extraction (SPE) system was able to remove the phenolic compounds effectively (90.84–98.49 %, 80.75–97.11 %, and 78.27–97.08 % for BPA, o-NTP, and PCP, respectively) . The MTAC cartridge packed SPE sorbent performance was compared to commercially produced C18 SPE cartridges and found to be comparable. All the parameters investigated were found to have a notable influence on the adsorption efficiency of the phenolic compounds from wastewaters at different magnitudes.
- Full Text:
- Date Issued: 2015
- Authors: Olorundare, O F , Msagati, T A M , Okonkwo, J O , Krause, Rui W M , Mamba, Bhekie B
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125331 , vital:35773 , https://doi.org/10.1007/s11356-014-3742-6
- Description: The determination and remediation of three phenolic compounds bisphenol A (BPA), ortho-nitrophenol (o-NTP), parachlorophenol (PCP) in wastewater is reported. The analysis of these molecules in wastewater was done using gas chromatography (GC) × GC time-of-flight mass spectrometry while activated carbon derived from maize tassel was used as an adsorbent. During the experimental procedures, the effect of various parameters such as initial concentration, pH of sample solution, eluent volume, and sample volume on the removal efficiency with respect to the three phenolic compounds was studied. The results showed that maize tassel produced activated carbon (MTAC) cartridge packed solid-phase extraction (SPE) system was able to remove the phenolic compounds effectively (90.84–98.49 %, 80.75–97.11 %, and 78.27–97.08 % for BPA, o-NTP, and PCP, respectively) . The MTAC cartridge packed SPE sorbent performance was compared to commercially produced C18 SPE cartridges and found to be comparable. All the parameters investigated were found to have a notable influence on the adsorption efficiency of the phenolic compounds from wastewaters at different magnitudes.
- Full Text:
- Date Issued: 2015
Tuning the redox properties of metalloporphyrin-and metallophthalocyanine-based molecular electrodes for the highest electrocatalytic activity in the oxidation of thiols
- Bedioui, Fethi, Griveau, Sophie, Nyokong, Tebello, Appleby, A John, Caro, Claudia A, Gulppi, Miguel, Ochoa, Gonzalo, Zagal, José H
- Authors: Bedioui, Fethi , Griveau, Sophie , Nyokong, Tebello , Appleby, A John , Caro, Claudia A , Gulppi, Miguel , Ochoa, Gonzalo , Zagal, José H
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/283988 , vital:56009 , xlink:href="https://doi.org/10.1039/B618767F"
- Description: In this work we discuss different approaches for achieving electrodes modified with N4 macrocyclic complexes for the catalysis of the electrochemical oxidation of thiols. These approaches involve adsorption, electropolymerization and molecular anchoring using self assembled monolayers. We also discuss the parameters that determine the reactivity of these complexes. Catalytic activity is associated with the nature of the central metal, redox potentials and Hammett parameters of substituents on the ligand. Correlations between catalytic activity (log i at constant E) and the redox potential of catalysts for complexes of Cr, Mn, Fe, Co, Ni and Cu are linear with an increase of activity for more positive redox potentials. For a great variety complexes bearing the same metal center (Co) correlations between log i and Eo′ of the Co(II)/Co(I) couple have the shape of an unsymmetric volcano. This indicates that the potential of the Co(II)/Co(I) couple can be tuned using the appropiate ligand to achieve maximum catalytic activity. Maximum activity probably corresponds to a ΔG of adsorption of the thiol on the Co center equal to zero, and to a coverage of active sites by the thiol equal to 0.5.
- Full Text:
- Date Issued: 2007
- Authors: Bedioui, Fethi , Griveau, Sophie , Nyokong, Tebello , Appleby, A John , Caro, Claudia A , Gulppi, Miguel , Ochoa, Gonzalo , Zagal, José H
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/283988 , vital:56009 , xlink:href="https://doi.org/10.1039/B618767F"
- Description: In this work we discuss different approaches for achieving electrodes modified with N4 macrocyclic complexes for the catalysis of the electrochemical oxidation of thiols. These approaches involve adsorption, electropolymerization and molecular anchoring using self assembled monolayers. We also discuss the parameters that determine the reactivity of these complexes. Catalytic activity is associated with the nature of the central metal, redox potentials and Hammett parameters of substituents on the ligand. Correlations between catalytic activity (log i at constant E) and the redox potential of catalysts for complexes of Cr, Mn, Fe, Co, Ni and Cu are linear with an increase of activity for more positive redox potentials. For a great variety complexes bearing the same metal center (Co) correlations between log i and Eo′ of the Co(II)/Co(I) couple have the shape of an unsymmetric volcano. This indicates that the potential of the Co(II)/Co(I) couple can be tuned using the appropiate ligand to achieve maximum catalytic activity. Maximum activity probably corresponds to a ΔG of adsorption of the thiol on the Co center equal to zero, and to a coverage of active sites by the thiol equal to 0.5.
- Full Text:
- Date Issued: 2007
An empirical investigation of the demand for money in South Africa within the inflation-targeting era
- Authors: Duah, Rachel
- Date: 2016
- Subjects: South Africa--Economic conditions http://id.loc.gov/authorities/subjects/sh85125465 , Inflation targeting--South Africa , Monetary policy--South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/19465 , vital:43127
- Description: The aim of the study is to empirically test the demand for money function in South Africa’s inflation-targeting era. This came from the fact that there have been a number of structural changes in the South African economy that have appeared to alter the relation between M3 and GDP and other macroeconomic variables. The study employed co-integration tests that showed one co-integrating equation which led to the application of the Vector-Error Correction Model (VECM) using the quarterly time series data covering the period from 2000-2015. The demand for money is investigated by estimating the real money balances as a function of Treasury Bills rate, income and total credit. Results showed that there is a negative relationship among Treasury Bills rate, income and real money balances. However, there is a positive relationship between real money balances and the total credit provided by the banking sector. The CUSUM and CUSUMQ tests are applied to examine the possibility of structural breaks in money demand functions, as well as parameter stability. The results of the study indicated that the estimated parameters for the short and long run dynamics of the real money demand function are stable. It was evident that Treasury bill rate, income and total credit can explain money balances and therefore can influence demand for money. The study recommends that the government ensures that there are economic activities such as employment creation which can then boost income levels so as to get a positive relationship between money balances and income. Through employment creation, there can be a reduction in borrowing. Treasury bill rates, being an effective monetary policy tool, can be used to direct monetary policy and also promote price stability. The study recommends that the South African Reserve Bank continue to improve the conditions in the financial sector. In this regard, the SARB and the government should strive to enact flexible policies that will boost financial credit and uplift business confidence. , Thesis (MCom)(Economics) -- University of Fort Hare, 2016
- Full Text:
- Date Issued: 2016
- Authors: Duah, Rachel
- Date: 2016
- Subjects: South Africa--Economic conditions http://id.loc.gov/authorities/subjects/sh85125465 , Inflation targeting--South Africa , Monetary policy--South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/19465 , vital:43127
- Description: The aim of the study is to empirically test the demand for money function in South Africa’s inflation-targeting era. This came from the fact that there have been a number of structural changes in the South African economy that have appeared to alter the relation between M3 and GDP and other macroeconomic variables. The study employed co-integration tests that showed one co-integrating equation which led to the application of the Vector-Error Correction Model (VECM) using the quarterly time series data covering the period from 2000-2015. The demand for money is investigated by estimating the real money balances as a function of Treasury Bills rate, income and total credit. Results showed that there is a negative relationship among Treasury Bills rate, income and real money balances. However, there is a positive relationship between real money balances and the total credit provided by the banking sector. The CUSUM and CUSUMQ tests are applied to examine the possibility of structural breaks in money demand functions, as well as parameter stability. The results of the study indicated that the estimated parameters for the short and long run dynamics of the real money demand function are stable. It was evident that Treasury bill rate, income and total credit can explain money balances and therefore can influence demand for money. The study recommends that the government ensures that there are economic activities such as employment creation which can then boost income levels so as to get a positive relationship between money balances and income. Through employment creation, there can be a reduction in borrowing. Treasury bill rates, being an effective monetary policy tool, can be used to direct monetary policy and also promote price stability. The study recommends that the South African Reserve Bank continue to improve the conditions in the financial sector. In this regard, the SARB and the government should strive to enact flexible policies that will boost financial credit and uplift business confidence. , Thesis (MCom)(Economics) -- University of Fort Hare, 2016
- Full Text:
- Date Issued: 2016
Direct and indirect effects of zooplanktivorous predators on the estuarine plankton community
- Authors: Wasserman, Ryan John
- Date: 2014
- Subjects: Zooplankton -- Effect of predation on , Predation (Biology) , Zooplankton -- Predators of , Copepoda
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5870 , http://hdl.handle.net/10962/d1012938
- Description: Although predation has been identified as a potentially important driver in terrestrial and freshwater ecosystems, estuarine planktonic research has focused largely on the so-called "bottom-up" drivers of community assemblages. As such, this thesis focuses on the direct and indirect effects of zooplanktivorous predators on the planktonic community in an estuarine environment. By using a suite of in situ mesocosm experiments, a number of hypotheses, pertaining to the major research themes associated with predator-prey interactions, are tested. These themes included trophic cascading, risk effects associated with predation events and the importance of predator diversity in maintaining prey communities. The first experiment assessed the significance of apex predation pressure for the planktonic community through trophic cascades. Various treatments using in situ mesocosms were established in a closed oligotrophic estuary to highlight the importance of predation in stabilising estuarine plankton abundances. Through either the removal (filtration) or addition of certain planktonic groups, varied trophic scenarios were established. The experimental treatment containing apex zooplanktivores had consequences for multiple trophic levels, exerting a stabilising pressure throughout the food web (Chapter 3). Furthermore, pyrosequencing of filtered water samples revealed that when compared to the remaining treatments, the treatment containing stable apex predatory pressure experienced limited temporal deviation-from-initial in bacterial community structure (Chapter 4). These findings are consistent with trophic cascade theory whereby predators mediate interactions at multiple lower trophic levels with consequent repercussions for diversity. To assess the non-consumptive effects of predators on prey, two experiments were conducted. Firstly, using egg numbers per clutch as a measure of potential reproductive output, the non-lethal effects of predatory pressure on reproductive success in a key planktonic copepod was investigated. In this study, the average clutch size of fecund female copepods was found to be consistently lower in the presence of predators when compared to females not exposed to predation threat (Chapter 5). The second study assessed the effects of conspecific chemical alarm cues associated with predation, on population dynamics of a copepod species. This study revealed that the copepods appear to detect the presence of chemical alarm cues associated with predation events, with repercussions for population demographics over time. Furthermore, it showed that in the absence of actual predation, copepod prey responses to alarm cues were adjusted over time, consistent with the threat sensitive predator avoidance hypothesis (Chapter 6). The final data chapter dealt with predator diversity and its implications for zooplankton community structure. By experimentally monitoring the effects of two alternate model predators on the metazoan community over time, dissimilarities in community level control emerged. Alternate key prey populations were regulated by the different model predators, highlighting the importance of predator and prey behaviour in mediating predator-prey interactions (Chapter 7). These results highlight the potential importance of predators in maintaining community dynamics in estuarine planktonic communities under certain conditions. This study represents some of the first work to address these various aspects of predator-prey dynamics within the context of planktonic estuarine ecology.
- Full Text:
- Date Issued: 2014
- Authors: Wasserman, Ryan John
- Date: 2014
- Subjects: Zooplankton -- Effect of predation on , Predation (Biology) , Zooplankton -- Predators of , Copepoda
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5870 , http://hdl.handle.net/10962/d1012938
- Description: Although predation has been identified as a potentially important driver in terrestrial and freshwater ecosystems, estuarine planktonic research has focused largely on the so-called "bottom-up" drivers of community assemblages. As such, this thesis focuses on the direct and indirect effects of zooplanktivorous predators on the planktonic community in an estuarine environment. By using a suite of in situ mesocosm experiments, a number of hypotheses, pertaining to the major research themes associated with predator-prey interactions, are tested. These themes included trophic cascading, risk effects associated with predation events and the importance of predator diversity in maintaining prey communities. The first experiment assessed the significance of apex predation pressure for the planktonic community through trophic cascades. Various treatments using in situ mesocosms were established in a closed oligotrophic estuary to highlight the importance of predation in stabilising estuarine plankton abundances. Through either the removal (filtration) or addition of certain planktonic groups, varied trophic scenarios were established. The experimental treatment containing apex zooplanktivores had consequences for multiple trophic levels, exerting a stabilising pressure throughout the food web (Chapter 3). Furthermore, pyrosequencing of filtered water samples revealed that when compared to the remaining treatments, the treatment containing stable apex predatory pressure experienced limited temporal deviation-from-initial in bacterial community structure (Chapter 4). These findings are consistent with trophic cascade theory whereby predators mediate interactions at multiple lower trophic levels with consequent repercussions for diversity. To assess the non-consumptive effects of predators on prey, two experiments were conducted. Firstly, using egg numbers per clutch as a measure of potential reproductive output, the non-lethal effects of predatory pressure on reproductive success in a key planktonic copepod was investigated. In this study, the average clutch size of fecund female copepods was found to be consistently lower in the presence of predators when compared to females not exposed to predation threat (Chapter 5). The second study assessed the effects of conspecific chemical alarm cues associated with predation, on population dynamics of a copepod species. This study revealed that the copepods appear to detect the presence of chemical alarm cues associated with predation events, with repercussions for population demographics over time. Furthermore, it showed that in the absence of actual predation, copepod prey responses to alarm cues were adjusted over time, consistent with the threat sensitive predator avoidance hypothesis (Chapter 6). The final data chapter dealt with predator diversity and its implications for zooplankton community structure. By experimentally monitoring the effects of two alternate model predators on the metazoan community over time, dissimilarities in community level control emerged. Alternate key prey populations were regulated by the different model predators, highlighting the importance of predator and prey behaviour in mediating predator-prey interactions (Chapter 7). These results highlight the potential importance of predators in maintaining community dynamics in estuarine planktonic communities under certain conditions. This study represents some of the first work to address these various aspects of predator-prey dynamics within the context of planktonic estuarine ecology.
- Full Text:
- Date Issued: 2014
An analysis of the link between monetary policy, exchange rate pass-through effect and domestic prices in South Africa.
- Authors: Ndamase, Asisipho Zingisa
- Date: 2022-02
- Subjects: Monetary policy. , South Africa--Economic policy.
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/22165 , vital:51992
- Description: The study seeks to analyse the link between monetary policy, domestic prices and exchange rate pass-through effect in South Africa. South Africa’s imports are more than its exports. Therefore, given a higher PTE associated with the importation of necessities, the poor are always left worse off since they are faced with imported inflation that is depreciating exchange rate driven. The Johansen co integration for the long run and the Vector Error Correctional Model for the short run were used to analyse monthly data obtained from the South African Reserve Bank (SARB) and the World Bank from 1990 to 2019. The study consisted of five separate but closely linked models, which are the price equation, excess demand equation, the monetary policy equation, pass through equation and the money demand equation. The results revealed that all models are cointegrated meaning that a long run relationship exist in these equations. However, the VECM short-run results show that two of the models have an ECM term which is negative and significant. The results indicated that there is evidence of the passthrough effect. In this case, a positive pass-through effect of 222 per cent was established between domestic prices and import prices. A pass-through effect of 39 per cent was also identified between imports and exchange rate and lastly a pass-through effect (PTE) of 30 percent was established between oil prices and import prices. , Thesis (MCom) (Economics) -- University of Fort Hare, 2022
- Full Text:
- Date Issued: 2022-02
- Authors: Ndamase, Asisipho Zingisa
- Date: 2022-02
- Subjects: Monetary policy. , South Africa--Economic policy.
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/22165 , vital:51992
- Description: The study seeks to analyse the link between monetary policy, domestic prices and exchange rate pass-through effect in South Africa. South Africa’s imports are more than its exports. Therefore, given a higher PTE associated with the importation of necessities, the poor are always left worse off since they are faced with imported inflation that is depreciating exchange rate driven. The Johansen co integration for the long run and the Vector Error Correctional Model for the short run were used to analyse monthly data obtained from the South African Reserve Bank (SARB) and the World Bank from 1990 to 2019. The study consisted of five separate but closely linked models, which are the price equation, excess demand equation, the monetary policy equation, pass through equation and the money demand equation. The results revealed that all models are cointegrated meaning that a long run relationship exist in these equations. However, the VECM short-run results show that two of the models have an ECM term which is negative and significant. The results indicated that there is evidence of the passthrough effect. In this case, a positive pass-through effect of 222 per cent was established between domestic prices and import prices. A pass-through effect of 39 per cent was also identified between imports and exchange rate and lastly a pass-through effect (PTE) of 30 percent was established between oil prices and import prices. , Thesis (MCom) (Economics) -- University of Fort Hare, 2022
- Full Text:
- Date Issued: 2022-02