Attitudes of isiXhosa-speaking students at the University of Fort Hare towards the use of isiXhosa as a language of learning and teaching (LOLT)
- Authors: Dalvit, Lorenzo
- Date: 2004
- Subjects: Native language and education -- South Africa -- Eastern Cape , Xhosa language -- Study and teaching (Higher) -- South Africa , English language -- Study and teaching (Higher) -- South Africa , Education, Bilingual , Language and education -- South Africa , Language policy -- South Africa , University of Fort Hare -- Students -- Attitudes
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2343 , http://hdl.handle.net/10962/d1002625 , Native language and education -- South Africa -- Eastern Cape , Xhosa language -- Study and teaching (Higher) -- South Africa , English language -- Study and teaching (Higher) -- South Africa , Education, Bilingual , Language and education -- South Africa , Language policy -- South Africa , University of Fort Hare -- Students -- Attitudes
- Description: The present work presents and discusses the results of a survey of a sample of isiXhosa-speaking students at the University of Fort Hare (Alice campus) and their attitudes towards the possible introduction of isiXhosa as a medium of instruction at this institution. More specifically, the research focuses on, among other things, the students’ attitudes towards English and isiXhosa and their opinions and beliefs about the introduction of dual-mediumship and its possible consequences. The survey methods used are a questionnaire survey as well as follow-up interviews, supplemented by on-campus observation. The results are first analysed as a whole, and then split into different categories according to a set of background variables (gender, year of study, subject studied etc). This analysis indicates that, while English is recognised as the dominant language in South Africa and, more specifically, in the domain of education, some categories of respondents acknowledge the usefulness of isiXhosa as an additional medium of instruction. This survey clearly shows that it makes little sense to present isiXhosa-speaking students with a rigid choice between the existing English-medium and a dual-medium (English and isiXhosa) policy. If dual-mediumship is ever to be implemented, respondents seem to consider the use of isiXhosa as a medium of instruction more appropriate in the first years of study, for selected subjects and in some domains within the academic context rather than others. This study is part of a growing set of surveys on the attitudes of university students towards the use of African languages in education, and can be fruitfully compared with similar research at other institutions. Moreover, the results of the present research can be used to inform future decisions regarding language policy at the University of Fort Hare.
- Full Text:
- Date Issued: 2004
- Authors: Dalvit, Lorenzo
- Date: 2004
- Subjects: Native language and education -- South Africa -- Eastern Cape , Xhosa language -- Study and teaching (Higher) -- South Africa , English language -- Study and teaching (Higher) -- South Africa , Education, Bilingual , Language and education -- South Africa , Language policy -- South Africa , University of Fort Hare -- Students -- Attitudes
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2343 , http://hdl.handle.net/10962/d1002625 , Native language and education -- South Africa -- Eastern Cape , Xhosa language -- Study and teaching (Higher) -- South Africa , English language -- Study and teaching (Higher) -- South Africa , Education, Bilingual , Language and education -- South Africa , Language policy -- South Africa , University of Fort Hare -- Students -- Attitudes
- Description: The present work presents and discusses the results of a survey of a sample of isiXhosa-speaking students at the University of Fort Hare (Alice campus) and their attitudes towards the possible introduction of isiXhosa as a medium of instruction at this institution. More specifically, the research focuses on, among other things, the students’ attitudes towards English and isiXhosa and their opinions and beliefs about the introduction of dual-mediumship and its possible consequences. The survey methods used are a questionnaire survey as well as follow-up interviews, supplemented by on-campus observation. The results are first analysed as a whole, and then split into different categories according to a set of background variables (gender, year of study, subject studied etc). This analysis indicates that, while English is recognised as the dominant language in South Africa and, more specifically, in the domain of education, some categories of respondents acknowledge the usefulness of isiXhosa as an additional medium of instruction. This survey clearly shows that it makes little sense to present isiXhosa-speaking students with a rigid choice between the existing English-medium and a dual-medium (English and isiXhosa) policy. If dual-mediumship is ever to be implemented, respondents seem to consider the use of isiXhosa as a medium of instruction more appropriate in the first years of study, for selected subjects and in some domains within the academic context rather than others. This study is part of a growing set of surveys on the attitudes of university students towards the use of African languages in education, and can be fruitfully compared with similar research at other institutions. Moreover, the results of the present research can be used to inform future decisions regarding language policy at the University of Fort Hare.
- Full Text:
- Date Issued: 2004
Bach
- Peterson, A., Composer not specified, Dargie, Dave
- Authors: Peterson, A. , Composer not specified , Dargie, Dave
- Date: 2004
- Subjects: Folk music , Sacred music , Field recordings , Africa, Sub-Saharan , Africa South Africa Alice sa
- Language: Language not specified
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/343314 , vital:62995 , International Library of African Music, Rhodes University, Makhanda, South Africa , Dave Dargie Field Tapes, Rhodes University, Makhanda, South Africa , DDC344b-05
- Description: Classical piano unaccompanied
- Full Text: false
- Date Issued: 2004
- Authors: Peterson, A. , Composer not specified , Dargie, Dave
- Date: 2004
- Subjects: Folk music , Sacred music , Field recordings , Africa, Sub-Saharan , Africa South Africa Alice sa
- Language: Language not specified
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/343314 , vital:62995 , International Library of African Music, Rhodes University, Makhanda, South Africa , Dave Dargie Field Tapes, Rhodes University, Makhanda, South Africa , DDC344b-05
- Description: Classical piano unaccompanied
- Full Text: false
- Date Issued: 2004
Becoming a journalist : a study into the professional socialisation and training of entry-level journalists at the Cape Argus newspaper
- Authors: Maughan, Karyn
- Date: 2004
- Subjects: Argus (Cape Town, South Africa) , Journalism -- Study and teaching -- South Africa , Journalists -- Training of -- South Africa , Journalists -- Selection and appointment -- South Africa , Journalists -- Education -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3507 , http://hdl.handle.net/10962/d1007553 , Argus (Cape Town, South Africa) , Journalism -- Study and teaching -- South Africa , Journalists -- Training of -- South Africa , Journalists -- Selection and appointment -- South Africa , Journalists -- Education -- South Africa
- Description: This thesis attempts to examine the construction of 'professionalism' within the newsroom of the Cape Argus, an English-medium newspaper in post-apartheid South Africa. It is a qualitative study which tries to evaluate how a particular mainstream media discourse of 'professionalism' is enacted and struggled over in the attitudes, behaviour and perceptions of entry-level journalists and news managers at the newspaper. It asks what the process of 'becoming a journalist' requires of entry-level journalists in terms of their previous education and personal qualities - and examines the newsroom strategies employed by news managers when entry-level journalists do not meet these particular requirements. This thesis looks at how the pressures of operating a daily English-language commercial newspaper may shape both the 'professional' expectations of news managers and their ability to positively contribute to entry-level journalists' 'newsroom training'. In attempting to examine the nature of journalistic 'professionalism', this study explores the ideology of knowledge construction within mainstream South African media. Operating from a 'radical democratic' perspective of journalism, which prioritises journalism as a vehicle for diverse social, cultural and political expression, this thesis suggests that South African media education needs to enable journalism students' understanding of the ideological construction of journalistic 'professionalism'.
- Full Text:
- Date Issued: 2004
- Authors: Maughan, Karyn
- Date: 2004
- Subjects: Argus (Cape Town, South Africa) , Journalism -- Study and teaching -- South Africa , Journalists -- Training of -- South Africa , Journalists -- Selection and appointment -- South Africa , Journalists -- Education -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3507 , http://hdl.handle.net/10962/d1007553 , Argus (Cape Town, South Africa) , Journalism -- Study and teaching -- South Africa , Journalists -- Training of -- South Africa , Journalists -- Selection and appointment -- South Africa , Journalists -- Education -- South Africa
- Description: This thesis attempts to examine the construction of 'professionalism' within the newsroom of the Cape Argus, an English-medium newspaper in post-apartheid South Africa. It is a qualitative study which tries to evaluate how a particular mainstream media discourse of 'professionalism' is enacted and struggled over in the attitudes, behaviour and perceptions of entry-level journalists and news managers at the newspaper. It asks what the process of 'becoming a journalist' requires of entry-level journalists in terms of their previous education and personal qualities - and examines the newsroom strategies employed by news managers when entry-level journalists do not meet these particular requirements. This thesis looks at how the pressures of operating a daily English-language commercial newspaper may shape both the 'professional' expectations of news managers and their ability to positively contribute to entry-level journalists' 'newsroom training'. In attempting to examine the nature of journalistic 'professionalism', this study explores the ideology of knowledge construction within mainstream South African media. Operating from a 'radical democratic' perspective of journalism, which prioritises journalism as a vehicle for diverse social, cultural and political expression, this thesis suggests that South African media education needs to enable journalism students' understanding of the ideological construction of journalistic 'professionalism'.
- Full Text:
- Date Issued: 2004
Biochemical characterization of plasmodium falciparum heat shock protein 70
- Matambo, Tonderayi Sylvester
- Authors: Matambo, Tonderayi Sylvester
- Date: 2004
- Subjects: Plasmodium falciparum , Malaria -- Prevention , Protein folding , Proteins -- Purification , Heat shock proteins
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4134 , http://hdl.handle.net/10962/d1015767
- Description: Plamodium falciparum heat shock protein (PfHsp70) is believed to be involved in the cytoprotection of the malaria parasite through its action as a molecular chaperone. Bioinformatic analysis reveal that PfHsp70 consists of the three canonical Hsp70 domains; an ATPase domain of 45 kDa, Substrate binding domain of 15 kDa and a C-terminal domain of 10 kDa. At the C-terminus there is a GGMP repeat motif that is commonly found in Hsp70s of parasitic origins. Plasmodium falciparum genome is 80% A-T rich, making it difficult to recombinantly express its proteins in Escherhia coli (E. coli) as a result of rare codon usage. In this study we carried out experiments to improve expression in E. coli by inserting the PfHsp70 coding region into the pQE30 expression vector. However multiple bands were detected by Western analysis, probably due to the presence of rare codons. The RIG plasmid, which encodes tRNAs for rare codons in particular Arg (AGA/AGG), Ile (AUA) and Gly (GGA) was engineered into the E. coli strain resulting in production of full length PfHsp70. Purification was achieved through Ni²⁺ Chelating sepharose under denaturing conditions. PfHsp70 was found to have a very low basal ATPase activity of 0.262 ± 0.05 nmoles/min/mg of protein. In the presence of reduced and carboxymethylated lactalbumin (RCMLA) a 11-fold increase in ATPase activity was noted whereas in the presence of both RCMLA and Trypanosoma cruzi DnaJ (Tcj2) a 16-fold was achieved. For ATP hydrolysis kcat value of 0.003 min⁻¹ was obtained whereas for ADP release a greater kcat value of 0.8 min⁻¹ was obtained. These results indicated that rate of ATP hydrolysis maybe the rate-determining step in the ATPase cycle of PfHsp70.
- Full Text:
- Date Issued: 2004
- Authors: Matambo, Tonderayi Sylvester
- Date: 2004
- Subjects: Plasmodium falciparum , Malaria -- Prevention , Protein folding , Proteins -- Purification , Heat shock proteins
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4134 , http://hdl.handle.net/10962/d1015767
- Description: Plamodium falciparum heat shock protein (PfHsp70) is believed to be involved in the cytoprotection of the malaria parasite through its action as a molecular chaperone. Bioinformatic analysis reveal that PfHsp70 consists of the three canonical Hsp70 domains; an ATPase domain of 45 kDa, Substrate binding domain of 15 kDa and a C-terminal domain of 10 kDa. At the C-terminus there is a GGMP repeat motif that is commonly found in Hsp70s of parasitic origins. Plasmodium falciparum genome is 80% A-T rich, making it difficult to recombinantly express its proteins in Escherhia coli (E. coli) as a result of rare codon usage. In this study we carried out experiments to improve expression in E. coli by inserting the PfHsp70 coding region into the pQE30 expression vector. However multiple bands were detected by Western analysis, probably due to the presence of rare codons. The RIG plasmid, which encodes tRNAs for rare codons in particular Arg (AGA/AGG), Ile (AUA) and Gly (GGA) was engineered into the E. coli strain resulting in production of full length PfHsp70. Purification was achieved through Ni²⁺ Chelating sepharose under denaturing conditions. PfHsp70 was found to have a very low basal ATPase activity of 0.262 ± 0.05 nmoles/min/mg of protein. In the presence of reduced and carboxymethylated lactalbumin (RCMLA) a 11-fold increase in ATPase activity was noted whereas in the presence of both RCMLA and Trypanosoma cruzi DnaJ (Tcj2) a 16-fold was achieved. For ATP hydrolysis kcat value of 0.003 min⁻¹ was obtained whereas for ADP release a greater kcat value of 0.8 min⁻¹ was obtained. These results indicated that rate of ATP hydrolysis maybe the rate-determining step in the ATPase cycle of PfHsp70.
- Full Text:
- Date Issued: 2004
Black and white rag
- Peterson, A., Composer not specified, Dargie, Dave
- Authors: Peterson, A. , Composer not specified , Dargie, Dave
- Date: 2004
- Subjects: Folk music , Sacred music , Field recordings , Africa, Sub-Saharan , Africa South Africa Alice sa
- Language: Language not specified
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/343287 , vital:62992 , International Library of African Music, Rhodes University, Makhanda, South Africa , Dave Dargie Field Tapes, Rhodes University, Makhanda, South Africa , DDC344b-04
- Description: Classical piano unaccompanied
- Full Text: false
- Date Issued: 2004
- Authors: Peterson, A. , Composer not specified , Dargie, Dave
- Date: 2004
- Subjects: Folk music , Sacred music , Field recordings , Africa, Sub-Saharan , Africa South Africa Alice sa
- Language: Language not specified
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/343287 , vital:62992 , International Library of African Music, Rhodes University, Makhanda, South Africa , Dave Dargie Field Tapes, Rhodes University, Makhanda, South Africa , DDC344b-04
- Description: Classical piano unaccompanied
- Full Text: false
- Date Issued: 2004
Black Business Executive Circle Award
- Date: 2004 , 2022-10-03
- Subjects: Bam, Brigalia , Bam, Brigalia -- Awards
- Language: English
- Type: realia
- Identifier: http://hdl.handle.net/10948/56722 , vital:57144
- Description: Black Business Executive Circle Award in recognition of Dr. Brigalia Bam for her outstanding performance in managing the 2004 elections. , Donated/gifted to Nelson Mandela University Archives , Forms part of: Brigalia Bam collection
- Full Text: false
- Date Issued: 2004
- Date: 2004 , 2022-10-03
- Subjects: Bam, Brigalia , Bam, Brigalia -- Awards
- Language: English
- Type: realia
- Identifier: http://hdl.handle.net/10948/56722 , vital:57144
- Description: Black Business Executive Circle Award in recognition of Dr. Brigalia Bam for her outstanding performance in managing the 2004 elections. , Donated/gifted to Nelson Mandela University Archives , Forms part of: Brigalia Bam collection
- Full Text: false
- Date Issued: 2004
Bollywood Twelfth Night: Steven Beresford's Production. Albery Theatre, London, September 2004: theatre review
- Authors: Wright, Laurence
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/455629 , vital:75444 , https://hdl.handle.net/10520/EJC48040
- Description: BOLLYWOOD TWELFTH NIGHT : Steven Beresford's Production. Albery Theatre, London, September 2004. LAURENCE WRIGHT A Bollywood Shakespeare? Why not? Steven Beresford's directorial debut in West End theatre was pleasant rather than stunning, and one came away with a sense of the possibilities he had envisioned, more than those he had realized. The show opens with a tropical monsoon, sponsor of comedy's shipwreck. The setting is present-day India, a run-down street in a large city.
- Full Text:
- Date Issued: 2004
- Authors: Wright, Laurence
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/455629 , vital:75444 , https://hdl.handle.net/10520/EJC48040
- Description: BOLLYWOOD TWELFTH NIGHT : Steven Beresford's Production. Albery Theatre, London, September 2004. LAURENCE WRIGHT A Bollywood Shakespeare? Why not? Steven Beresford's directorial debut in West End theatre was pleasant rather than stunning, and one came away with a sense of the possibilities he had envisioned, more than those he had realized. The show opens with a tropical monsoon, sponsor of comedy's shipwreck. The setting is present-day India, a run-down street in a large city.
- Full Text:
- Date Issued: 2004
Burial practices, African women, and Islam in the Eastern Cape province, South Africa
- Authors: Sesanti, Simphiwe Olicius
- Date: 2004
- Subjects: Islamic funeral rites and ceremonies -- South Africa -- Eastern Cape , Muslim women -- South Africa -- Eastern Cape , Mourning custom -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10998 , http://hdl.handle.net/10948/346 , Islamic funeral rites and ceremonies -- South Africa -- Eastern Cape , Muslim women -- South Africa -- Eastern Cape , Mourning custom -- South Africa -- Eastern Cape
- Description: Early in 2003, African Muslims in Uitenhage’s township, Kwa-Nobuhle, learnt that Muslim women, led by Sheikh Nceba Salamntu, in South Africa’s Port Elizabeth New Brighton township, were allowed, contrary to previous practice, to follow a funeral procession right up to the graveyard. The resultant discomfort on the one hand, and excitement on the other caused by this event among Muslims in the township, forms the basis of this research. It gives focus to Muslim women, the ones most affected by their customary restriction from the gravesites. The researchi exposes the basis for women’s exclusion from funeral processions in the Muslim community. It was established that many of these Muslim women who challenged the practice were converts from Christianity to Islam. One of the bases for their action was that they were passive recipients of Islam. Furthermore, it was found that the exclusion of women from the funeral procession has no basis in Islamic writings.
- Full Text:
- Date Issued: 2004
- Authors: Sesanti, Simphiwe Olicius
- Date: 2004
- Subjects: Islamic funeral rites and ceremonies -- South Africa -- Eastern Cape , Muslim women -- South Africa -- Eastern Cape , Mourning custom -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10998 , http://hdl.handle.net/10948/346 , Islamic funeral rites and ceremonies -- South Africa -- Eastern Cape , Muslim women -- South Africa -- Eastern Cape , Mourning custom -- South Africa -- Eastern Cape
- Description: Early in 2003, African Muslims in Uitenhage’s township, Kwa-Nobuhle, learnt that Muslim women, led by Sheikh Nceba Salamntu, in South Africa’s Port Elizabeth New Brighton township, were allowed, contrary to previous practice, to follow a funeral procession right up to the graveyard. The resultant discomfort on the one hand, and excitement on the other caused by this event among Muslims in the township, forms the basis of this research. It gives focus to Muslim women, the ones most affected by their customary restriction from the gravesites. The researchi exposes the basis for women’s exclusion from funeral processions in the Muslim community. It was established that many of these Muslim women who challenged the practice were converts from Christianity to Islam. One of the bases for their action was that they were passive recipients of Islam. Furthermore, it was found that the exclusion of women from the funeral procession has no basis in Islamic writings.
- Full Text:
- Date Issued: 2004
Capsule immobilisation of sulphate-reducing bacteria and application in disarticulated systems
- Authors: Sanyahumbi, Douglas
- Date: 2004
- Subjects: Sulfur bacteria , Water -- Purification -- Biological treatment
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3935 , http://hdl.handle.net/10962/d1003994
- Description: Biotechnology of sulphate reducing bacteria has developed rapidly in recent years with the recognition of their extensive and diverse biocatalytic potential. However, their application in a number of areas has been constrained due to problems including poor cell retention within the continuous bioprocess reactor environment, and contamination of the treated stream with residual organic feed components and cell biomass. These problems have so far excluded the application of biological sulphate reduction in the treatment of ‘clean’ inorganic waste streams where components such as sulphate, acidity and heavy metal contamination require treatment. This study investigated the effective immobilisation of sulphate reducing bacterial cultures and proposed that the disarticulation of the electron donor and carbon source supply using such systems would create the basis for their application in the treatment of ‘clean’ inorganic waste streams. A functional and stable sulphate reducing culture was selected and following evaluation using a number of techniques, was immobilised by encapsulation within a calcium-alginate-xanthum gum membrane to give robust capsules with good sulphate reduction activity. The concept of disarticulation was investigated in a swing-back cycle where the carbon source was excluded and the electron donor supplied in the form of hydrogen gas in a continuous up-flow capsule-packed column reactor. Following a period of operation in this mode (4-12 days), the system was swung back to a carbon feed to supply requirements of cell maintenance (2-3 days). Three types of synthetic ‘clean’ inorganic waste stream treatments were investigated, including sulphate removal, neutralisation of acidity and heavy metal (copper and lead) removal. The results showed: • Sulphate removal at a rate of 50 mg SO₄²⁻L/day/g initial wet mass of capsules during three 4-day cycles of electron donor phase. This was comparable to the performance of free cell systems; • Neutralisation of acidity where influent pH values of 2.4 and 4.0 were elevated to above pH 7.5; • Copper removal of 99 and 85 % was achieved with initial copper concentrations of 2 and 60 mg/L respectively; • Percentage lead removal values of 49 and 78 % were achieved; This first report on the application of the concept of capsular immobilisation and disarticulation in the treatment of ‘clean’ inorganic waste streams will require future studies in order to extend the development of the full potential of the concept.
- Full Text:
- Date Issued: 2004
- Authors: Sanyahumbi, Douglas
- Date: 2004
- Subjects: Sulfur bacteria , Water -- Purification -- Biological treatment
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3935 , http://hdl.handle.net/10962/d1003994
- Description: Biotechnology of sulphate reducing bacteria has developed rapidly in recent years with the recognition of their extensive and diverse biocatalytic potential. However, their application in a number of areas has been constrained due to problems including poor cell retention within the continuous bioprocess reactor environment, and contamination of the treated stream with residual organic feed components and cell biomass. These problems have so far excluded the application of biological sulphate reduction in the treatment of ‘clean’ inorganic waste streams where components such as sulphate, acidity and heavy metal contamination require treatment. This study investigated the effective immobilisation of sulphate reducing bacterial cultures and proposed that the disarticulation of the electron donor and carbon source supply using such systems would create the basis for their application in the treatment of ‘clean’ inorganic waste streams. A functional and stable sulphate reducing culture was selected and following evaluation using a number of techniques, was immobilised by encapsulation within a calcium-alginate-xanthum gum membrane to give robust capsules with good sulphate reduction activity. The concept of disarticulation was investigated in a swing-back cycle where the carbon source was excluded and the electron donor supplied in the form of hydrogen gas in a continuous up-flow capsule-packed column reactor. Following a period of operation in this mode (4-12 days), the system was swung back to a carbon feed to supply requirements of cell maintenance (2-3 days). Three types of synthetic ‘clean’ inorganic waste stream treatments were investigated, including sulphate removal, neutralisation of acidity and heavy metal (copper and lead) removal. The results showed: • Sulphate removal at a rate of 50 mg SO₄²⁻L/day/g initial wet mass of capsules during three 4-day cycles of electron donor phase. This was comparable to the performance of free cell systems; • Neutralisation of acidity where influent pH values of 2.4 and 4.0 were elevated to above pH 7.5; • Copper removal of 99 and 85 % was achieved with initial copper concentrations of 2 and 60 mg/L respectively; • Percentage lead removal values of 49 and 78 % were achieved; This first report on the application of the concept of capsular immobilisation and disarticulation in the treatment of ‘clean’ inorganic waste streams will require future studies in order to extend the development of the full potential of the concept.
- Full Text:
- Date Issued: 2004
Catalytic activity of iron and cobalt phthalocyanine complexes towards the oxidation of cyclohexene using tert-butylhydroperoxide and chloroperoxybenzoic acid
- Sehlotho, Nthapo, Nyokong, Tebello
- Authors: Sehlotho, Nthapo , Nyokong, Tebello
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/290257 , vital:56729 , xlink:href="https://doi.org/10.1016/j.molcata.2003.08.014"
- Description: Cyclohexene oxidation using tert-butylhydroperoxide (TBHP) or chloroperoxybenzoic acid (CPBA) in the presence of iron(II) polychlorophthalocyanine (Cl16PcFe), iron(II) phthalocyanine (PcFe) and cobalt(II) phthalocyanine (PcCo), results in the formation of the following products: cyclohexene oxide, 2-cyclohexene-1-ol and 2-cyclohexene-1-one. Adipic acid was also formed after long reaction times. The selectivity for 2-cyclohexene-1-one is favoured when Cl16PcFe or PcCo catalysts are employed, while PcFe is selective towards the formation of 2-cyclohexene-1-ol. The Cl16PcFe catalyst is transformed into a μ-oxo dimer (Cl16PcFeIIIOIIIFePcCl16) during the oxidation process. The catalytic process using the unsubstituted PcCoII and PcFeII catalysts involved PcMIII species as an intermediate. The active form of the Cl16PcFe catalyst was stable to degradation in that it was still active even after 4 weeks of continued catalysis.
- Full Text:
- Date Issued: 2004
- Authors: Sehlotho, Nthapo , Nyokong, Tebello
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/290257 , vital:56729 , xlink:href="https://doi.org/10.1016/j.molcata.2003.08.014"
- Description: Cyclohexene oxidation using tert-butylhydroperoxide (TBHP) or chloroperoxybenzoic acid (CPBA) in the presence of iron(II) polychlorophthalocyanine (Cl16PcFe), iron(II) phthalocyanine (PcFe) and cobalt(II) phthalocyanine (PcCo), results in the formation of the following products: cyclohexene oxide, 2-cyclohexene-1-ol and 2-cyclohexene-1-one. Adipic acid was also formed after long reaction times. The selectivity for 2-cyclohexene-1-one is favoured when Cl16PcFe or PcCo catalysts are employed, while PcFe is selective towards the formation of 2-cyclohexene-1-ol. The Cl16PcFe catalyst is transformed into a μ-oxo dimer (Cl16PcFeIIIOIIIFePcCl16) during the oxidation process. The catalytic process using the unsubstituted PcCoII and PcFeII catalysts involved PcMIII species as an intermediate. The active form of the Cl16PcFe catalyst was stable to degradation in that it was still active even after 4 weeks of continued catalysis.
- Full Text:
- Date Issued: 2004
Changes in energy use patterns in the Bushbuckridge Lowveld of the Limpopo Province, South Africa: eleven years on
- Authors: Madubansi, Mainza
- Date: 2004
- Subjects: Energy consumption -- South Africa -- Limpopo
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4756 , http://hdl.handle.net/10962/d1007139 , Energy consumption -- South Africa -- Limpopo
- Description: This research reports on the energy transition that has taken place in the Bushbuckridge district between 1991 and 2002. It is a follow up to a similar study that was done in 1991 investigating a number of aspects of energy use. It uses the 1991 study as a baseline and aims to explore how the passage of time, growth of the local population and changes in incomes and the availability of fuels have affected the patterns of fuel use in the region in the past eleven years. A structured interview approach was used for most aspects of the study. The interview schedule included sections on types, amounts and reasons for use and non-use of 13 different energy sources as well as data on income levels, household size and other economic parameters. Analysis of the consumption patterns of the different fuel types revealed that between the two survey periods, households in the sample settlements went through some pronounced changes in patterns of fuel use, particularly those that had acquired electricity. The introduction of electricity in the region had certainly played a major role in spurring the energy transition. Fuels that were previously used for lighting, powering entertainment appliances and refrigeration had been displaced by electricity. In terms of cooking and other thermal application, however, the vast majority of households in all the sample settlements continued using fuelwood and complemented it to a lesser extent with paraffin and electricity. In both surveys, the use or non-use of available fuels in the region was influenced by several factors. Common reasons for non-use of certain fuel types included expense, lack of appliances, the risk involved in using such fuels and the preference for other fuels. Reasons for use were mainly related to the low cost of the fuel and the fuel’s ability to meet particular end uses. Although incomes in the region had increased between 1991 and 2002, they were still below the poverty line. Activities from which households obtained their income remained the same. Old age pension, migrant wages and the informal sector remained the largest contributors of income to most households. Other indicators of relative wealth and poverty, like ownership of vehicles, bicycles and beds remained the same.
- Full Text:
- Date Issued: 2004
- Authors: Madubansi, Mainza
- Date: 2004
- Subjects: Energy consumption -- South Africa -- Limpopo
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4756 , http://hdl.handle.net/10962/d1007139 , Energy consumption -- South Africa -- Limpopo
- Description: This research reports on the energy transition that has taken place in the Bushbuckridge district between 1991 and 2002. It is a follow up to a similar study that was done in 1991 investigating a number of aspects of energy use. It uses the 1991 study as a baseline and aims to explore how the passage of time, growth of the local population and changes in incomes and the availability of fuels have affected the patterns of fuel use in the region in the past eleven years. A structured interview approach was used for most aspects of the study. The interview schedule included sections on types, amounts and reasons for use and non-use of 13 different energy sources as well as data on income levels, household size and other economic parameters. Analysis of the consumption patterns of the different fuel types revealed that between the two survey periods, households in the sample settlements went through some pronounced changes in patterns of fuel use, particularly those that had acquired electricity. The introduction of electricity in the region had certainly played a major role in spurring the energy transition. Fuels that were previously used for lighting, powering entertainment appliances and refrigeration had been displaced by electricity. In terms of cooking and other thermal application, however, the vast majority of households in all the sample settlements continued using fuelwood and complemented it to a lesser extent with paraffin and electricity. In both surveys, the use or non-use of available fuels in the region was influenced by several factors. Common reasons for non-use of certain fuel types included expense, lack of appliances, the risk involved in using such fuels and the preference for other fuels. Reasons for use were mainly related to the low cost of the fuel and the fuel’s ability to meet particular end uses. Although incomes in the region had increased between 1991 and 2002, they were still below the poverty line. Activities from which households obtained their income remained the same. Old age pension, migrant wages and the informal sector remained the largest contributors of income to most households. Other indicators of relative wealth and poverty, like ownership of vehicles, bicycles and beds remained the same.
- Full Text:
- Date Issued: 2004
Characterisation of the J domain aminoacid residues important for the interaction of DNAJ-like proteins with HSP70 chaperones
- Authors: Hennessy, Fritha
- Date: 2004
- Subjects: Heat shock proteins Protein folding Proteins -- Analysis Proteins -- Structure Molecular chaperones
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3937 , http://hdl.handle.net/10962/d1003996
- Description: The 70 kDa heat shock proteins (Hsp70s) are vital for normal protein folding, as they stabilise the unfolded state of nascent polypeptides, allowing these sufficient time to attain a correct tertiary structure. Hsp70s are aided by the DnaJ-like family of proteins, which interact with Hsp70s in order to enhance the chaperone activity of these proteins. DnaJ-like proteins contain a J domain, a seventy amino acid domain consisting of four α-helices, which is defined by the presence of an invariant tripeptide of histidine, proline and aspartic acid (HPD motif). This motif is key to the interaction between DnaJ-like proteins and Hsp70s. This thesis has focused on determining the presence of other conserved residues in the J domain and their role in mediating the interaction of DnaJ-like proteins with partner Hsp70s. DnaJ-like proteins from Agrobacterium tumefaciens RUOR were isolated and used as a model system. A. tumefaciens DnaJ (Agt DnaJ) was able to replace the lack of E. coli DnaJ in an E. coli null mutant strain, however, additional A. tumefaciens DnaJ-like proteins Agt DjC1/DjlA, Agt DjC2 and Agt DjC5 were unable to complement for the lack of E. coli DnaJ. Replacement of the Agt DnaJ J domain with J domains from these proteins resulted in non-functional chimeric proteins, despite some sequence conservation. The kinetics of the basal specific ATPase activity of Agt DnaK, and its ability to have this activity stimulated by Agt DnaJ and Agt DnaJ-H33Q were also investigated. Stimulation of the ATPase activity by Agt DnaJ ranged between 1.5 to 2 fold, but Agt DnaJ-H33Q was unable to stimulate the basal ATPase activity. Conserved amino acids in the J domain were identified in silico, and these residues were substituted in the J domain of Agt DnaJ. The ability of these derivative proteins to replace E. coli DnaJ was investigated. Alterations in the HPD motif gave rise to proteins unable to complement for lack of E. coli DnaJ, consistent with literature. Agt DnaJ-R26A was unable to replace E. coli DnaJ suggesting that Arg26 could be key to the interaction with partner Hsp70s. Agt DnaJ-D59A was unable to replace E. coli DnaJ; substitutions in Asp59 have not previously been shown to impact on the function of DnaJ. Substituting Arg63 in Agt DnaJ abrogated the levels of complementation. Substitution of several structural residues was also found to disrupt the in vivo function of Agt DnaJ suggesting that the maintenance of the structural integrity of the J domain was important for function. This study has identified a number of residues critical to the structure and function of the J domain of Agt DnaJ, and potentially of general importance as molecular determinants for DnaJ-Hsp70 interaction.
- Full Text:
- Date Issued: 2004
- Authors: Hennessy, Fritha
- Date: 2004
- Subjects: Heat shock proteins Protein folding Proteins -- Analysis Proteins -- Structure Molecular chaperones
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3937 , http://hdl.handle.net/10962/d1003996
- Description: The 70 kDa heat shock proteins (Hsp70s) are vital for normal protein folding, as they stabilise the unfolded state of nascent polypeptides, allowing these sufficient time to attain a correct tertiary structure. Hsp70s are aided by the DnaJ-like family of proteins, which interact with Hsp70s in order to enhance the chaperone activity of these proteins. DnaJ-like proteins contain a J domain, a seventy amino acid domain consisting of four α-helices, which is defined by the presence of an invariant tripeptide of histidine, proline and aspartic acid (HPD motif). This motif is key to the interaction between DnaJ-like proteins and Hsp70s. This thesis has focused on determining the presence of other conserved residues in the J domain and their role in mediating the interaction of DnaJ-like proteins with partner Hsp70s. DnaJ-like proteins from Agrobacterium tumefaciens RUOR were isolated and used as a model system. A. tumefaciens DnaJ (Agt DnaJ) was able to replace the lack of E. coli DnaJ in an E. coli null mutant strain, however, additional A. tumefaciens DnaJ-like proteins Agt DjC1/DjlA, Agt DjC2 and Agt DjC5 were unable to complement for the lack of E. coli DnaJ. Replacement of the Agt DnaJ J domain with J domains from these proteins resulted in non-functional chimeric proteins, despite some sequence conservation. The kinetics of the basal specific ATPase activity of Agt DnaK, and its ability to have this activity stimulated by Agt DnaJ and Agt DnaJ-H33Q were also investigated. Stimulation of the ATPase activity by Agt DnaJ ranged between 1.5 to 2 fold, but Agt DnaJ-H33Q was unable to stimulate the basal ATPase activity. Conserved amino acids in the J domain were identified in silico, and these residues were substituted in the J domain of Agt DnaJ. The ability of these derivative proteins to replace E. coli DnaJ was investigated. Alterations in the HPD motif gave rise to proteins unable to complement for lack of E. coli DnaJ, consistent with literature. Agt DnaJ-R26A was unable to replace E. coli DnaJ suggesting that Arg26 could be key to the interaction with partner Hsp70s. Agt DnaJ-D59A was unable to replace E. coli DnaJ; substitutions in Asp59 have not previously been shown to impact on the function of DnaJ. Substituting Arg63 in Agt DnaJ abrogated the levels of complementation. Substitution of several structural residues was also found to disrupt the in vivo function of Agt DnaJ suggesting that the maintenance of the structural integrity of the J domain was important for function. This study has identified a number of residues critical to the structure and function of the J domain of Agt DnaJ, and potentially of general importance as molecular determinants for DnaJ-Hsp70 interaction.
- Full Text:
- Date Issued: 2004
Cleaning of fouled membranes using enzymes from a sulphidogenic bioreactor
- Authors: Melamane, Xolisa L
- Date: 2004
- Subjects: Membrane filters , Membrane filters -- Fouling , Enzymes -- Biotechnology , Enzymes -- Purification , Water -- Purification -- Membrane filtration , Ultrafiltration
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4133 , http://hdl.handle.net/10962/d1015764
- Description: Maintenance of membrane performance requires inevitable cleaning or defouling of fouled membranes. Membrane cleaning using enzymes such as proteases, lipases, α-glucosidases from a sulphidogenic bioreactor was investigated. At first, dilute and concentrated enzyme extract were prepared form the sulphidogenic pellet. Enzyme assays on 0.5 % azocaisen, 1 % triacetin and 1 mg/ml ρ-nitrophenyl-α-D-glucopyranoside were performed using the concentrated enzyme extract (0 – 200 mg/ml). For membrane fouling, an abattoir effluent was obtained from Ostritech Pty (Ltd), Grahamstown, South Africa. The effluent was characterised for presence of potential foulants such as lipids, proteins, amino acids and carbohydrates. Static fouling of polysulphone membranes (0.22 μm, 47 mm) was then performed using the abattoir effluent. Cleaning of the fouled membranes was also performed using at first the dilute and then the concentrated form (200 mg/ml) of enzyme extracts. Qualitative and quantitative biochemical analysis for proteins, lipids and carbohydrates was performed to ascertain the presence of foulants on polysulphone membranes and their removal by dilute or concentrated enzyme extracts. The ability of dilute enzyme extracts to remove proteins lipids, and carbohydrates fouling capillary UF membrane module; their ability to restore permeate fluxes and transmembrane pressure after cleaning/defouling was also investigated. Permeate volumes from this UF membrane module were analysed for protein, amino acids, lipids, and carbohydrates concentrations after fouling and defouling. Fouling was further characterized by standard blocking, cake filtration and pore blocking models using stirred UF cell and polyethersulphone membranes with MWCO of 30 000, 100 000 and 300 000. After characterization of fouling, polyethersulphone membranes with MWCO of 30 000 and 300 000 were defouled using the concentrated enzyme extract (100 mg ml). Enzyme activities at 200 mg/ml of enzyme concentration were 8.071 IU, 86.71 IU and 789.02 IU for proteases, lipases and α-glucosidases. The abattoir effluent contained 553 μg/ml of lipid, 301 μg/ml of protein, 141 μg/ml of total carbohydrate, and 0.63 μg/ml of total reducing sugars. Proteins, lipids and carbohydrates fouling polysulphone membranes after a day were removed by 23.4 %, when a dilute enzyme was used. A concentrated enzyme extract of 200 mg/ml was able to remove proteins, lipids and carbohydrates up to 5 days of fouling by 100 %, 82 %, 71 %, 68 % and 76 % respectively. Defouling of dynamically fouled capillary ultrafiltration membranes using sulphidogenic proteases was successful at pH 10, 37°C, within 1 hour. Sulphidogenic proteases activity was 2.1 U/ml and flux Recovery (FR %) was 64. Characterization of fouling revealed that proteins and lipids were major foulants while low concentration of carbohydrates fouled polyethersulphone membranes. Fouling followed standard blocking for 10 minutes in all the membranes; afterwards fouling adopted cake filtration model for membranes with 30 000 MWCO and pore blocking model for membranes with 300 000 MWCO. A concentration of 100 mg/ml of enzyme extract was able to remove fouling from membranes with MWCO of 30 000. Defouling membranes that followed pore blocking model i.e. 300 000 MWCO was not successful due to a mass transfer problem. From the results of defouling of 30 000 and 300 000 MWCO it was concluded that defouling of cake layer fouling (30 000 MWCO) was successful while defouling of pore blocking fouling was unsuccessful due to a mass transfer problem. The ratio of enzymes present in the enzyme extract when calculated based on enzymatic activity for proteases, lipases and α-glucosidases was 1.1 %, 11 % and 87.9 %. It was hypothesized that apart from proteases, lipases, α and β-glucosidases; phosphatases, sulphatases, amonipeptidases etc. from a sulphidogenic bioreactor clean or defoul cake layer fouling by organic foulants and pore blocking fouling provided the mass transfer problem is solved. However, concentration of enzymes from a sulphidogenic bioreactor has not been optimized yet. Other methods of concentrating the enzyme extract can be investigated for example use of organic solvents.
- Full Text:
- Date Issued: 2004
- Authors: Melamane, Xolisa L
- Date: 2004
- Subjects: Membrane filters , Membrane filters -- Fouling , Enzymes -- Biotechnology , Enzymes -- Purification , Water -- Purification -- Membrane filtration , Ultrafiltration
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4133 , http://hdl.handle.net/10962/d1015764
- Description: Maintenance of membrane performance requires inevitable cleaning or defouling of fouled membranes. Membrane cleaning using enzymes such as proteases, lipases, α-glucosidases from a sulphidogenic bioreactor was investigated. At first, dilute and concentrated enzyme extract were prepared form the sulphidogenic pellet. Enzyme assays on 0.5 % azocaisen, 1 % triacetin and 1 mg/ml ρ-nitrophenyl-α-D-glucopyranoside were performed using the concentrated enzyme extract (0 – 200 mg/ml). For membrane fouling, an abattoir effluent was obtained from Ostritech Pty (Ltd), Grahamstown, South Africa. The effluent was characterised for presence of potential foulants such as lipids, proteins, amino acids and carbohydrates. Static fouling of polysulphone membranes (0.22 μm, 47 mm) was then performed using the abattoir effluent. Cleaning of the fouled membranes was also performed using at first the dilute and then the concentrated form (200 mg/ml) of enzyme extracts. Qualitative and quantitative biochemical analysis for proteins, lipids and carbohydrates was performed to ascertain the presence of foulants on polysulphone membranes and their removal by dilute or concentrated enzyme extracts. The ability of dilute enzyme extracts to remove proteins lipids, and carbohydrates fouling capillary UF membrane module; their ability to restore permeate fluxes and transmembrane pressure after cleaning/defouling was also investigated. Permeate volumes from this UF membrane module were analysed for protein, amino acids, lipids, and carbohydrates concentrations after fouling and defouling. Fouling was further characterized by standard blocking, cake filtration and pore blocking models using stirred UF cell and polyethersulphone membranes with MWCO of 30 000, 100 000 and 300 000. After characterization of fouling, polyethersulphone membranes with MWCO of 30 000 and 300 000 were defouled using the concentrated enzyme extract (100 mg ml). Enzyme activities at 200 mg/ml of enzyme concentration were 8.071 IU, 86.71 IU and 789.02 IU for proteases, lipases and α-glucosidases. The abattoir effluent contained 553 μg/ml of lipid, 301 μg/ml of protein, 141 μg/ml of total carbohydrate, and 0.63 μg/ml of total reducing sugars. Proteins, lipids and carbohydrates fouling polysulphone membranes after a day were removed by 23.4 %, when a dilute enzyme was used. A concentrated enzyme extract of 200 mg/ml was able to remove proteins, lipids and carbohydrates up to 5 days of fouling by 100 %, 82 %, 71 %, 68 % and 76 % respectively. Defouling of dynamically fouled capillary ultrafiltration membranes using sulphidogenic proteases was successful at pH 10, 37°C, within 1 hour. Sulphidogenic proteases activity was 2.1 U/ml and flux Recovery (FR %) was 64. Characterization of fouling revealed that proteins and lipids were major foulants while low concentration of carbohydrates fouled polyethersulphone membranes. Fouling followed standard blocking for 10 minutes in all the membranes; afterwards fouling adopted cake filtration model for membranes with 30 000 MWCO and pore blocking model for membranes with 300 000 MWCO. A concentration of 100 mg/ml of enzyme extract was able to remove fouling from membranes with MWCO of 30 000. Defouling membranes that followed pore blocking model i.e. 300 000 MWCO was not successful due to a mass transfer problem. From the results of defouling of 30 000 and 300 000 MWCO it was concluded that defouling of cake layer fouling (30 000 MWCO) was successful while defouling of pore blocking fouling was unsuccessful due to a mass transfer problem. The ratio of enzymes present in the enzyme extract when calculated based on enzymatic activity for proteases, lipases and α-glucosidases was 1.1 %, 11 % and 87.9 %. It was hypothesized that apart from proteases, lipases, α and β-glucosidases; phosphatases, sulphatases, amonipeptidases etc. from a sulphidogenic bioreactor clean or defoul cake layer fouling by organic foulants and pore blocking fouling provided the mass transfer problem is solved. However, concentration of enzymes from a sulphidogenic bioreactor has not been optimized yet. Other methods of concentrating the enzyme extract can be investigated for example use of organic solvents.
- Full Text:
- Date Issued: 2004
Comparison of two granulation processes with the view to reduce manufacturing cost
- Authors: Maclean, Aldritt Allister
- Date: 2004
- Subjects: Drugs -- Granulation , Tablets (Medicine) , Pharmaceutical industry
- Language: English
- Type: Thesis , Masters , MTech (Chemistry)
- Identifier: vital:10980 , http://hdl.handle.net/10948/210 , Drugs -- Granulation , Tablets (Medicine) , Pharmaceutical industry
- Description: Aspen Pharmacare, one of the leading pharmaceutical manufacturers in South Africa has embarked on a programme of improving the production processes currently employed at their Port Elizabeth site. With the introduction of new technology at the site and the move towards globalization, it became imperative that Aspen remain competitive in the market. The product of interest in this research, Degoran Plus tablets, is one of the company’s leading brand sellers. Upon investigation, it became apparent that this product created opportunity for process improvement using the new technology. The manufacture of Degoran Plus entails granulation, compression and coating of the product. Most opportunity for improvement was possible in the granulation stage because of the laborious nature of the present process. Degoran Plus tablets had a history of analytical failures, especially with regard to the dissolution rate of the final product, as well as other quality related issues. The product was not considered to be a “through-runner”, which resulted in bad production output, due to continual repeats of not only analysis but also reworks in production. A strategic decision was taken to manufacture Degoran Plus using the Collette Gral granulator as the equipment offered superior mixing capability when compared to the Bear planetary granulator. It was assumed that the granulation process would result in more uniform distribution of the actives. Upon producing a better granule, a final product of superior quality would be attained. The validation protocol stipulates that three samples be taken and tested from the powder mix. Nine samples taken from granulated bulk are treated in the same manner. The validation protocol further stipulates that the first three batches manufactured utilise the new process, and tested according to the protocol. The results obtained from the analysis are evaluated statistically and a conclusion and recommendation were derived based on the evaluation.
- Full Text:
- Date Issued: 2004
- Authors: Maclean, Aldritt Allister
- Date: 2004
- Subjects: Drugs -- Granulation , Tablets (Medicine) , Pharmaceutical industry
- Language: English
- Type: Thesis , Masters , MTech (Chemistry)
- Identifier: vital:10980 , http://hdl.handle.net/10948/210 , Drugs -- Granulation , Tablets (Medicine) , Pharmaceutical industry
- Description: Aspen Pharmacare, one of the leading pharmaceutical manufacturers in South Africa has embarked on a programme of improving the production processes currently employed at their Port Elizabeth site. With the introduction of new technology at the site and the move towards globalization, it became imperative that Aspen remain competitive in the market. The product of interest in this research, Degoran Plus tablets, is one of the company’s leading brand sellers. Upon investigation, it became apparent that this product created opportunity for process improvement using the new technology. The manufacture of Degoran Plus entails granulation, compression and coating of the product. Most opportunity for improvement was possible in the granulation stage because of the laborious nature of the present process. Degoran Plus tablets had a history of analytical failures, especially with regard to the dissolution rate of the final product, as well as other quality related issues. The product was not considered to be a “through-runner”, which resulted in bad production output, due to continual repeats of not only analysis but also reworks in production. A strategic decision was taken to manufacture Degoran Plus using the Collette Gral granulator as the equipment offered superior mixing capability when compared to the Bear planetary granulator. It was assumed that the granulation process would result in more uniform distribution of the actives. Upon producing a better granule, a final product of superior quality would be attained. The validation protocol stipulates that three samples be taken and tested from the powder mix. Nine samples taken from granulated bulk are treated in the same manner. The validation protocol further stipulates that the first three batches manufactured utilise the new process, and tested according to the protocol. The results obtained from the analysis are evaluated statistically and a conclusion and recommendation were derived based on the evaluation.
- Full Text:
- Date Issued: 2004
Competition for attachment of aquaculture candidate probiotic and pathogenic bacteria on fish intestinal mucus:
- Vine, Niall G, Leukes, Winston D, Kaiser, Horst, Daya, Santylal, Baxter, Jeremy, Hecht, Thomas
- Authors: Vine, Niall G , Leukes, Winston D , Kaiser, Horst , Daya, Santylal , Baxter, Jeremy , Hecht, Thomas
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142819 , vital:38120 , DOI: 10.1111/j.1365-2761.2004.00542.x
- Description: Probiotics for aquaculture are generally only selected by their ability to produce antimicrobial metabolites; however, attachment to intestinal mucus is important in order to remain within the gut of its host. Five candidate probiotics (AP1–AP5), isolated from the clownfish, Amphiprion percula (Lacepéde), were examined for their ability to attach to fish intestinal mucus and compete with two pathogens, Aeromonas hydrophila and Vibrio alginolyticus. Two different radioactive isotopes were used to quantify competition between pathogens and probionts. Attachment of the pathogens was enhanced by the presence of the candidate probiotics. However, the addition of the candidate probiotics after the pathogens resulted in reduced pathogen attachment.
- Full Text:
- Date Issued: 2004
- Authors: Vine, Niall G , Leukes, Winston D , Kaiser, Horst , Daya, Santylal , Baxter, Jeremy , Hecht, Thomas
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142819 , vital:38120 , DOI: 10.1111/j.1365-2761.2004.00542.x
- Description: Probiotics for aquaculture are generally only selected by their ability to produce antimicrobial metabolites; however, attachment to intestinal mucus is important in order to remain within the gut of its host. Five candidate probiotics (AP1–AP5), isolated from the clownfish, Amphiprion percula (Lacepéde), were examined for their ability to attach to fish intestinal mucus and compete with two pathogens, Aeromonas hydrophila and Vibrio alginolyticus. Two different radioactive isotopes were used to quantify competition between pathogens and probionts. Attachment of the pathogens was enhanced by the presence of the candidate probiotics. However, the addition of the candidate probiotics after the pathogens resulted in reduced pathogen attachment.
- Full Text:
- Date Issued: 2004
Composition portfolio
- Authors: Prince, Lloyd T
- Date: 2004
- Subjects: Music -- South Africa Composition (Music)
- Language: English
- Type: Thesis , Masters , MMus
- Identifier: vital:2652 , http://hdl.handle.net/10962/d1002318
- Full Text:
- Date Issued: 2004
- Authors: Prince, Lloyd T
- Date: 2004
- Subjects: Music -- South Africa Composition (Music)
- Language: English
- Type: Thesis , Masters , MMus
- Identifier: vital:2652 , http://hdl.handle.net/10962/d1002318
- Full Text:
- Date Issued: 2004
Concerning secondary thermoluminescence peaks in α-Al_2_O_3_:C
- Authors: Chithambo, Makaiko L
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6793 , http://hdl.handle.net/10962/d1003823
- Description: Thermoluminescence characteristics of two subsidiary glow peaks, one below 100°C and the other above 300°C, have been studied for measurements between 30°C and 500°C in α-Al_2_O_3_:C. The thermoluminescence intensity of the lower temperature peak decreased with storage with a half-life of about 150 s. In contrast, the intensity of the higher temperature peak increased with storage towards some maximum. The peak-temperature of each of the secondary glow peaks was essentially constant with dose, whereas that of the main peak decreased with irradiation. The dose response for the three peaks was similar except for sublinear growth in the higher temperature peak at low dose values. These effects are discussed in terms of changes in the concentration of F+ luminescence precursors brought about by competitive electron retrapping at deep electron-traps or hole-traps. This work refines the physics and application of α-Al_2_O_3_:C luminescence in radiation dosimetry.
- Full Text:
- Date Issued: 2004
- Authors: Chithambo, Makaiko L
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6793 , http://hdl.handle.net/10962/d1003823
- Description: Thermoluminescence characteristics of two subsidiary glow peaks, one below 100°C and the other above 300°C, have been studied for measurements between 30°C and 500°C in α-Al_2_O_3_:C. The thermoluminescence intensity of the lower temperature peak decreased with storage with a half-life of about 150 s. In contrast, the intensity of the higher temperature peak increased with storage towards some maximum. The peak-temperature of each of the secondary glow peaks was essentially constant with dose, whereas that of the main peak decreased with irradiation. The dose response for the three peaks was similar except for sublinear growth in the higher temperature peak at low dose values. These effects are discussed in terms of changes in the concentration of F+ luminescence precursors brought about by competitive electron retrapping at deep electron-traps or hole-traps. This work refines the physics and application of α-Al_2_O_3_:C luminescence in radiation dosimetry.
- Full Text:
- Date Issued: 2004
Constructing a cardinal measure of democratic development in a transition polity: the Nigerian example
- Dinneya, Godson E, Tsegaye, Asrat
- Authors: Dinneya, Godson E , Tsegaye, Asrat
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6076 , http://hdl.handle.net/10962/d1003837
- Description: Existing measures of the level of democracy present in a given state treat democracy as a product and therefore place undue emphasis on actual freedoms enjoyed by the citizens of the country. In transition polities where the actual levels of freedom are low despite continuing efforts to democratize, democracy should be seen as a process rather than a product. A measure that dilutes the end product to capture today's struggles against undemocratic structures and policies does so in order to recognize the foundations these inputs lay for future democratic development. Nigeria exemplifies the many polities in transition on the African continent. This essay looks at the major political events that typify the processes of power change, quality of governance, political environment and democratic dividends, and uses them to construct democratization indices to determine the pattern and level of democratization in Nigeria since political independence. This exercise sets the stage for assessing the impacts of various dimensions of democratization on the performance of the Nigerian economy.
- Full Text:
- Date Issued: 2004
- Authors: Dinneya, Godson E , Tsegaye, Asrat
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6076 , http://hdl.handle.net/10962/d1003837
- Description: Existing measures of the level of democracy present in a given state treat democracy as a product and therefore place undue emphasis on actual freedoms enjoyed by the citizens of the country. In transition polities where the actual levels of freedom are low despite continuing efforts to democratize, democracy should be seen as a process rather than a product. A measure that dilutes the end product to capture today's struggles against undemocratic structures and policies does so in order to recognize the foundations these inputs lay for future democratic development. Nigeria exemplifies the many polities in transition on the African continent. This essay looks at the major political events that typify the processes of power change, quality of governance, political environment and democratic dividends, and uses them to construct democratization indices to determine the pattern and level of democratization in Nigeria since political independence. This exercise sets the stage for assessing the impacts of various dimensions of democratization on the performance of the Nigerian economy.
- Full Text:
- Date Issued: 2004
Consumer decision making styles: a comparative study among Motswana, Chinese and South African students
- Authors: Li, Yuejin
- Date: 2004
- Subjects: Consumer behavior -- China , Consumer behavior -- Botswana , Consumer behavior -- South Africa , Young consumers , Caucasian race
- Language: English
- Type: Thesis , Masters , MTech (Marketing)
- Identifier: vital:10771 , http://hdl.handle.net/10948/154 , Consumer behavior -- China , Consumer behavior -- Botswana , Consumer behavior -- South Africa , Young consumers , Caucasian race
- Description: As the global marketplace becomes more integrated and consumer specialists develop an international focus, developing useful scales to profile consumer decision-making styles in other cultures becomes important. Comparing the decision-making styles of consumers from different countries would thus contribute to the understanding of the effect of the marketing environment as well as of the cultural factors on consumer decision-making styles. It would also be significant to determine if the decision-making styles of foreign consumers differ from those of local ones. The influx of foreign students enrolled at South African Universities and Technikons has resulted in an increase in the number of consumers who have to make purchases connected to their daily lives within a different cultural environment. An understanding of students as consumers and their decisionmaking processes is important to marketers, particularly as students are recognised as a specialised market segment for a variety of goods and services. It would thus be significant to determine if the decision-making styles of foreign students differ from those of local students. This exploratory study investigates the decision-making styles among Chinese, Motswana and South African Caucasian students in a South African context, with a view of verifying the international applicability of the Consumer Styles Inventory (CSI) developed by Sproles and Kendall (1986). Only students with a Caucasian background were included in an attempt to avoid the influence of the different subcultures amongst South African students. It was found that Sproles and Kendall’s (1986) model did not fit the South African samples. It was furthermore found that differences exist among Motswana, Chinese and Caucasian students in consumer decision-making styles. The mean value for the “Novelty-fashion conscious” style was number one in the list of factors for Chinese and Motswana students and second for the Caucasian sample. “Price conscious” style, however, was number one for the Caucasian students.
- Full Text:
- Date Issued: 2004
- Authors: Li, Yuejin
- Date: 2004
- Subjects: Consumer behavior -- China , Consumer behavior -- Botswana , Consumer behavior -- South Africa , Young consumers , Caucasian race
- Language: English
- Type: Thesis , Masters , MTech (Marketing)
- Identifier: vital:10771 , http://hdl.handle.net/10948/154 , Consumer behavior -- China , Consumer behavior -- Botswana , Consumer behavior -- South Africa , Young consumers , Caucasian race
- Description: As the global marketplace becomes more integrated and consumer specialists develop an international focus, developing useful scales to profile consumer decision-making styles in other cultures becomes important. Comparing the decision-making styles of consumers from different countries would thus contribute to the understanding of the effect of the marketing environment as well as of the cultural factors on consumer decision-making styles. It would also be significant to determine if the decision-making styles of foreign consumers differ from those of local ones. The influx of foreign students enrolled at South African Universities and Technikons has resulted in an increase in the number of consumers who have to make purchases connected to their daily lives within a different cultural environment. An understanding of students as consumers and their decisionmaking processes is important to marketers, particularly as students are recognised as a specialised market segment for a variety of goods and services. It would thus be significant to determine if the decision-making styles of foreign students differ from those of local students. This exploratory study investigates the decision-making styles among Chinese, Motswana and South African Caucasian students in a South African context, with a view of verifying the international applicability of the Consumer Styles Inventory (CSI) developed by Sproles and Kendall (1986). Only students with a Caucasian background were included in an attempt to avoid the influence of the different subcultures amongst South African students. It was found that Sproles and Kendall’s (1986) model did not fit the South African samples. It was furthermore found that differences exist among Motswana, Chinese and Caucasian students in consumer decision-making styles. The mean value for the “Novelty-fashion conscious” style was number one in the list of factors for Chinese and Motswana students and second for the Caucasian sample. “Price conscious” style, however, was number one for the Caucasian students.
- Full Text:
- Date Issued: 2004
Contested rights : the impact of game farming on farm workers in the Bushmen's River area
- Authors: Luck, Kelly
- Date: 2004
- Subjects: Game farms -- South Africa -- Eastern Cape , Agricultural laborers -- South Africa -- Eastern Cape -- Social conditions Agricultural laborers -- South Africa -- Eastern Cape -- Economic conditions Agricultural laborers -- Political aspects -- South Africa -- Eastern Cape Agricultural laborers -- Legal status, laws, etc. -- South Africa -- Eastern Cape Agricultural laborers -- Protection -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2104 , http://hdl.handle.net/10962/d1004144
- Description: This thesis is an investigation of the impact of commercial game farming on former farm workers in the Bushman's River area of the Eastern Cape. In its examination of the broader economic and political changes that have facilitated a move from agriculture to game farming, it analyses how these changes affect farm workers. The main concern of the thesis is the ways in which farm workers (at the local level) respond to changes at the national and global level (legal and political changes, the advent of tourism, and the injection of foreign capital and businessmen into the area). Lack of knowledge about their rights under the current political dispensation, as well as the perceived need for mediation between themselves and foreign landowners, points to a general sense of powerlessness. Feelings of alienation from local government structures aimed at fulfilling this function indicate a significant gap between the statute at the national level and the local reality. Local reality is informed by a strong conservatism which is generated by African Independent Church structures and local Xhosa perceptions of manhood and respectability. This conservative discourse leads to a frame of reference which is largely informed by pre-1994 interactions with farmers and government. This results in a situation in which farm workers, largely unaware of their rights in the new dispensation, operate as they did in the past; waiting for landowners to decide their fate for them. What ensues is a lack of meaningful interaction with government and landowners, perpetuating their subjugation and cynicism as to whether government structures are in fact working in their interests. The thesis comes to three main conclusions. The first is that game farming has been negatively received by farm workers due to the associated threats of unemployment and eviction. The second is that despite high levels of subjugation, even the very poor are agents to some degree. The creation of a masculine identity which is internally articulated, as opposed to outwardly expressed, and the grounding of reputation in the family suggest that farm workers have developed mechanisms to deal with their disempowered position. Lastly, farm workers are in possession of social capital which has made it possible for them to deal with their low status in the societal hierarchy. This includes the Church, family and fellow community members. These coping strategies have however proved a disadvantage in the current era because they prevent direct communication with landowners, government and NGOs.
- Full Text:
- Date Issued: 2004
- Authors: Luck, Kelly
- Date: 2004
- Subjects: Game farms -- South Africa -- Eastern Cape , Agricultural laborers -- South Africa -- Eastern Cape -- Social conditions Agricultural laborers -- South Africa -- Eastern Cape -- Economic conditions Agricultural laborers -- Political aspects -- South Africa -- Eastern Cape Agricultural laborers -- Legal status, laws, etc. -- South Africa -- Eastern Cape Agricultural laborers -- Protection -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2104 , http://hdl.handle.net/10962/d1004144
- Description: This thesis is an investigation of the impact of commercial game farming on former farm workers in the Bushman's River area of the Eastern Cape. In its examination of the broader economic and political changes that have facilitated a move from agriculture to game farming, it analyses how these changes affect farm workers. The main concern of the thesis is the ways in which farm workers (at the local level) respond to changes at the national and global level (legal and political changes, the advent of tourism, and the injection of foreign capital and businessmen into the area). Lack of knowledge about their rights under the current political dispensation, as well as the perceived need for mediation between themselves and foreign landowners, points to a general sense of powerlessness. Feelings of alienation from local government structures aimed at fulfilling this function indicate a significant gap between the statute at the national level and the local reality. Local reality is informed by a strong conservatism which is generated by African Independent Church structures and local Xhosa perceptions of manhood and respectability. This conservative discourse leads to a frame of reference which is largely informed by pre-1994 interactions with farmers and government. This results in a situation in which farm workers, largely unaware of their rights in the new dispensation, operate as they did in the past; waiting for landowners to decide their fate for them. What ensues is a lack of meaningful interaction with government and landowners, perpetuating their subjugation and cynicism as to whether government structures are in fact working in their interests. The thesis comes to three main conclusions. The first is that game farming has been negatively received by farm workers due to the associated threats of unemployment and eviction. The second is that despite high levels of subjugation, even the very poor are agents to some degree. The creation of a masculine identity which is internally articulated, as opposed to outwardly expressed, and the grounding of reputation in the family suggest that farm workers have developed mechanisms to deal with their disempowered position. Lastly, farm workers are in possession of social capital which has made it possible for them to deal with their low status in the societal hierarchy. This includes the Church, family and fellow community members. These coping strategies have however proved a disadvantage in the current era because they prevent direct communication with landowners, government and NGOs.
- Full Text:
- Date Issued: 2004