Synthesis and photophysical properties of a covalently linked porphyrin-phthalocyanine conjugate
- Zhao, Zhixin, Ogunsipe, Abimbola O, Maree, M David, Nyokong, Tebello
- Authors: Zhao, Zhixin , Ogunsipe, Abimbola O , Maree, M David , Nyokong, Tebello
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/300358 , vital:57922 , xlink:href="https://doi.org/10.1142/S1088424605000253"
- Description: The synthesis of a phthalocyanine-porphyrin heteropentamer (zinc(II) tetra(5-phenoxy-10,15,20-triphenylporphyrin)) zinc(II) phthalocyanine, (ZnPc-(ZnTPP)4), containing four units of zinc tetraphenylporphyrin linked to a central zinc phthalocyanine macrocycle via an ether linkage is reported. The photophysical parameters of the pentamer are reported in toluene and dimethyl sulfoxide (DMSO). The observed differences in the fluorescence behavior of the pentamer in the two solvents is explained in terms of emission from different states; charge transfer state in DMSO and locally excited state in toluene. The rate constants for fluorescence, intersystem crossing, internal conversion, and of charge and energy transfer are reported for the pentamer. Quantum yields for fluorescence, internal conversion, triplet state and of charge and energy transfer are also reported for the pentamer, ZnPc-(ZnTPP)4 and the mixture of ZnPc and ZnTPP. The latter two parameters are higher in the pentamer compared to a mixture containing ZnPc and ZnTPP.
- Full Text:
- Date Issued: 2005
- Authors: Zhao, Zhixin , Ogunsipe, Abimbola O , Maree, M David , Nyokong, Tebello
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/300358 , vital:57922 , xlink:href="https://doi.org/10.1142/S1088424605000253"
- Description: The synthesis of a phthalocyanine-porphyrin heteropentamer (zinc(II) tetra(5-phenoxy-10,15,20-triphenylporphyrin)) zinc(II) phthalocyanine, (ZnPc-(ZnTPP)4), containing four units of zinc tetraphenylporphyrin linked to a central zinc phthalocyanine macrocycle via an ether linkage is reported. The photophysical parameters of the pentamer are reported in toluene and dimethyl sulfoxide (DMSO). The observed differences in the fluorescence behavior of the pentamer in the two solvents is explained in terms of emission from different states; charge transfer state in DMSO and locally excited state in toluene. The rate constants for fluorescence, intersystem crossing, internal conversion, and of charge and energy transfer are reported for the pentamer. Quantum yields for fluorescence, internal conversion, triplet state and of charge and energy transfer are also reported for the pentamer, ZnPc-(ZnTPP)4 and the mixture of ZnPc and ZnTPP. The latter two parameters are higher in the pentamer compared to a mixture containing ZnPc and ZnTPP.
- Full Text:
- Date Issued: 2005
The relevance of (South African) Renaissance studies
- Authors: Wright, Laurence
- Date: 2005
- Language: English
- Type: text , article
- Identifier: vital:7055 , http://hdl.handle.net/10962/d1007416 , https://www.ajol.info/index.php/sisa/article/view/40550
- Description: preprint , This paper is part of a longer piece devoted to the elucidation of two related propositions. The first is that in South Africa the humanities in general, and Renaissance Studies in particular, are stymied by a lack of strategic thinking from those in the academy. The second is that the humanities, and Renaissance Studies, and Shakespeare, are valid and needed in this country, possibly as never before. This paper tackles the latter question, the challenge of intrinsic relevance. What possible bearing have art and literature, politics and religion, customs and technologies developed 10,000 kilometres away and nearly half a millennium ago to do with South Africa in the 21st century? I steal up on the main issue by outlining an abbreviated rhetoric of relevance, establishing a framework within which intrinsic relevance can be conceptualised for Renaissance Studies today.
- Full Text:
- Date Issued: 2005
- Authors: Wright, Laurence
- Date: 2005
- Language: English
- Type: text , article
- Identifier: vital:7055 , http://hdl.handle.net/10962/d1007416 , https://www.ajol.info/index.php/sisa/article/view/40550
- Description: preprint , This paper is part of a longer piece devoted to the elucidation of two related propositions. The first is that in South Africa the humanities in general, and Renaissance Studies in particular, are stymied by a lack of strategic thinking from those in the academy. The second is that the humanities, and Renaissance Studies, and Shakespeare, are valid and needed in this country, possibly as never before. This paper tackles the latter question, the challenge of intrinsic relevance. What possible bearing have art and literature, politics and religion, customs and technologies developed 10,000 kilometres away and nearly half a millennium ago to do with South Africa in the 21st century? I steal up on the main issue by outlining an abbreviated rhetoric of relevance, establishing a framework within which intrinsic relevance can be conceptualised for Renaissance Studies today.
- Full Text:
- Date Issued: 2005
Book Review:‘These Traits Portend’: review of Thabo Mbeki and the Struggle for the Soul of the ANC by William Mervyn Gumede
- Authors: Wright, Laurence
- Date: 2005
- Language: English
- Type: text , article
- Identifier: vital:7049 , http://hdl.handle.net/10962/d1007391 , https://www.researchgate.net/publication/29807204_Book_Review_'These_Traits_Portend'_Review_of_Thabo_Mbeki_and_the_Struggle_for_the_Soul_of_the_ANC_by_William_Mervyn_Gumede_Cape_Town_Zebra_Press_2005
- Description: preprint , “The identity of the old ANC is changing fast and its soul is becoming harder to locate” – so writes William Gumede in his best-selling account of the Mbeki presidency. This is a thoroughly admirable book, critical, informed and deeply concerned with the welfare of the people of South Africa, especially the poor – with no taint of political hagiography. The central plank of the critique concerns the ANC’s management of the economy. Gumede’s account of the genesis of GEAR and the devious way it was sprung on the tri-partite alliance is illuminating. It was done under the rubric of necessary modernization, according to Gumede, and allegiance to the Blair/Schroeder Third Way. But there were huge ancillary consequences: the loss of influence by the ordinary ANC membership, neglect of branch activity, sidelining of the parliamentary caucus, centralization of policy development in the office of the president, increasing reliance on consultants and relentless cosying up to big business.
- Full Text:
- Date Issued: 2005
- Authors: Wright, Laurence
- Date: 2005
- Language: English
- Type: text , article
- Identifier: vital:7049 , http://hdl.handle.net/10962/d1007391 , https://www.researchgate.net/publication/29807204_Book_Review_'These_Traits_Portend'_Review_of_Thabo_Mbeki_and_the_Struggle_for_the_Soul_of_the_ANC_by_William_Mervyn_Gumede_Cape_Town_Zebra_Press_2005
- Description: preprint , “The identity of the old ANC is changing fast and its soul is becoming harder to locate” – so writes William Gumede in his best-selling account of the Mbeki presidency. This is a thoroughly admirable book, critical, informed and deeply concerned with the welfare of the people of South Africa, especially the poor – with no taint of political hagiography. The central plank of the critique concerns the ANC’s management of the economy. Gumede’s account of the genesis of GEAR and the devious way it was sprung on the tri-partite alliance is illuminating. It was done under the rubric of necessary modernization, according to Gumede, and allegiance to the Blair/Schroeder Third Way. But there were huge ancillary consequences: the loss of influence by the ordinary ANC membership, neglect of branch activity, sidelining of the parliamentary caucus, centralization of policy development in the office of the president, increasing reliance on consultants and relentless cosying up to big business.
- Full Text:
- Date Issued: 2005
Bycatch and discarding in the South African demersal trawl fishery
- Walmsley, Sarah A, Leslie, Rob W, Sauer, Warwick H H
- Authors: Walmsley, Sarah A , Leslie, Rob W , Sauer, Warwick H H
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123944 , vital:35518 , https://doi.10.1016/j.fishres.2007.03.002
- Description: Observers aboard commercial trawlers collected data on the total catch composition of 614 and 479 hauls made by vessels operating off the south and west coasts of South Africa, respectively. On the south coast, four fishing areas were identified on the basis of target species and fishing depth. On the west coast, hauls were separated into those targeting hake Merluccius spp. in four depth ranges (0–300, 301–400, 401–500, and >500 m) and those targeting monkfish Lophius vomerinus. For each area, the catch composition was calculated and the species assemblages were investigated using cluster analysis and multi-dimensional scaling. Finally, for each coast, the weight of fish discarded annually was estimated. On the south coast, although hake dominated, between 21% and 47% of the catch was not hake, depending on the fishing area. In comparison, hake dominated west coast catches, the proportion of hake increasing with depth. For each fishery investigated, approximately 90% of the catch was processed and landed. However, estimates of annual discards indicate that the south and west coast fisheries may annually discard 9000 or 10,000 t and 17,000 or 25,000 t, of undersized and unutilizable fish and offal, respectively, depending on the estimation method used. When developing strategies to limit or enhance utilization of bycatch, cognisance should be taken of the differences in catch composition between the south and west coasts and of the importance of bycatch revenue to south coast fishing companies.
- Full Text:
- Date Issued: 2007
- Authors: Walmsley, Sarah A , Leslie, Rob W , Sauer, Warwick H H
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123944 , vital:35518 , https://doi.10.1016/j.fishres.2007.03.002
- Description: Observers aboard commercial trawlers collected data on the total catch composition of 614 and 479 hauls made by vessels operating off the south and west coasts of South Africa, respectively. On the south coast, four fishing areas were identified on the basis of target species and fishing depth. On the west coast, hauls were separated into those targeting hake Merluccius spp. in four depth ranges (0–300, 301–400, 401–500, and >500 m) and those targeting monkfish Lophius vomerinus. For each area, the catch composition was calculated and the species assemblages were investigated using cluster analysis and multi-dimensional scaling. Finally, for each coast, the weight of fish discarded annually was estimated. On the south coast, although hake dominated, between 21% and 47% of the catch was not hake, depending on the fishing area. In comparison, hake dominated west coast catches, the proportion of hake increasing with depth. For each fishery investigated, approximately 90% of the catch was processed and landed. However, estimates of annual discards indicate that the south and west coast fisheries may annually discard 9000 or 10,000 t and 17,000 or 25,000 t, of undersized and unutilizable fish and offal, respectively, depending on the estimation method used. When developing strategies to limit or enhance utilization of bycatch, cognisance should be taken of the differences in catch composition between the south and west coasts and of the importance of bycatch revenue to south coast fishing companies.
- Full Text:
- Date Issued: 2007
Primary caregivers' experience of raising children with autism: a phenomenological perspective
- Authors: Swanepoel, Yolandi
- Date: 2005
- Subjects: Autism in children Autistic children Autism in children -- Diagnosis Parents of autistic children
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:3067 , http://hdl.handle.net/10962/d1002576
- Description: Autism occupies an extreme position among childhood pathologies due to its severity, duration and impact on the family. In this qualitative study, four primary caregivers of autistic children were interviewed regarding their experiences of the diagnostic process, their post-diagnostic adjustment, and how helping professionals can improve their service rendering to these families. This study utilised a phenomenological approach to look at primary caregivers as the best-informed authority to explore and describe their lived realities and experiences of raising their autistic children in South Africa. The rationale for a phenomenological approach in this study is that such an interpretative inquiry enables material to be collected and analysed within the specific context of the subjective realities of primary caregivers of autistic children in South Africa. The researcher utilised semi-structured, in-depth, face-to-face interviews as method of data collection. Each participant was interviewed over the course of three separate interviews. The themes and categories that resulted from a content analysis of the material were grouped into two broad fields of experience, namely: (1) experiences surrounding the diagnostic process; and (2) the pervasive influence of autism on different areas of family life. In terms of experiences surrounding children’s diagnosis, four themes were identified: (1) Being a new parent and making sense out of chaos; (2) Responsibility and blame; (3) Confusion and disillusionment during early experiences with helping professionals; and (4) Feelings about the diagnosis. The pervasive influence of autism on different areas of family life includes: (5) Strained family relationships; (6) Challenges of behaviour management and disciplining the autistic child; (7) Challenges of finding suitable resources for education and day-care; and (8) Maintaining the family unit and doing things as a family.
- Full Text:
- Date Issued: 2005
- Authors: Swanepoel, Yolandi
- Date: 2005
- Subjects: Autism in children Autistic children Autism in children -- Diagnosis Parents of autistic children
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:3067 , http://hdl.handle.net/10962/d1002576
- Description: Autism occupies an extreme position among childhood pathologies due to its severity, duration and impact on the family. In this qualitative study, four primary caregivers of autistic children were interviewed regarding their experiences of the diagnostic process, their post-diagnostic adjustment, and how helping professionals can improve their service rendering to these families. This study utilised a phenomenological approach to look at primary caregivers as the best-informed authority to explore and describe their lived realities and experiences of raising their autistic children in South Africa. The rationale for a phenomenological approach in this study is that such an interpretative inquiry enables material to be collected and analysed within the specific context of the subjective realities of primary caregivers of autistic children in South Africa. The researcher utilised semi-structured, in-depth, face-to-face interviews as method of data collection. Each participant was interviewed over the course of three separate interviews. The themes and categories that resulted from a content analysis of the material were grouped into two broad fields of experience, namely: (1) experiences surrounding the diagnostic process; and (2) the pervasive influence of autism on different areas of family life. In terms of experiences surrounding children’s diagnosis, four themes were identified: (1) Being a new parent and making sense out of chaos; (2) Responsibility and blame; (3) Confusion and disillusionment during early experiences with helping professionals; and (4) Feelings about the diagnosis. The pervasive influence of autism on different areas of family life includes: (5) Strained family relationships; (6) Challenges of behaviour management and disciplining the autistic child; (7) Challenges of finding suitable resources for education and day-care; and (8) Maintaining the family unit and doing things as a family.
- Full Text:
- Date Issued: 2005
Thinking about South African tabloid newspapers:
- Strelitz, Larry N, Steenveld, Lynette N
- Authors: Strelitz, Larry N , Steenveld, Lynette N
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159825 , vital:40347 , DOI: 10.1080/02560054.2005.9653337
- Description: A popular view of tabloids is that they pander to the lowest common denominator of public taste, they simplify complex issues, and they generally fail to provide information that citizens need in order to make informed political judgments - the latter being the raison d’etre of serious newspapers. In summary, tabloids “lower the standards of public discourse” (Ornerbring and Jonson, 2004:283).
- Full Text:
- Date Issued: 2010
- Authors: Strelitz, Larry N , Steenveld, Lynette N
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159825 , vital:40347 , DOI: 10.1080/02560054.2005.9653337
- Description: A popular view of tabloids is that they pander to the lowest common denominator of public taste, they simplify complex issues, and they generally fail to provide information that citizens need in order to make informed political judgments - the latter being the raison d’etre of serious newspapers. In summary, tabloids “lower the standards of public discourse” (Ornerbring and Jonson, 2004:283).
- Full Text:
- Date Issued: 2010
You can’t be serious:
- Strelitz, Larry N, Steenveld, Lynette N
- Authors: Strelitz, Larry N , Steenveld, Lynette N
- Date: 2005
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159215 , vital:40278 , https://hdl.handle.net/10520/EJC146377
- Description: As well as pandering to the lowest common denominator and simplifying complex issues, tabloids are also condemned for generally failing to provide information that citizens need in order to make informed political judgements - the latter being the raison d'etre of serious newspapers. In summary, tabloids "lower the standards of public discourse" (Ornerbring and Jonson, 2004: 283).
- Full Text:
- Date Issued: 2005
- Authors: Strelitz, Larry N , Steenveld, Lynette N
- Date: 2005
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159215 , vital:40278 , https://hdl.handle.net/10520/EJC146377
- Description: As well as pandering to the lowest common denominator and simplifying complex issues, tabloids are also condemned for generally failing to provide information that citizens need in order to make informed political judgements - the latter being the raison d'etre of serious newspapers. In summary, tabloids "lower the standards of public discourse" (Ornerbring and Jonson, 2004: 283).
- Full Text:
- Date Issued: 2005
An embracing Africanism:
- Authors: Strelitz, Larry N
- Date: 2005
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159266 , vital:40282 , https://hdl.handle.net/10520/EJC146405
- Description: "African journalism" is a composite term, each element of which is problematic, and is open to differing interpretations. I'll deal with each in turn. An identity of any sort is always relational. Thus "Africa" and things "African" have meaning in relation to what is non-African - usually European or American.
- Full Text:
- Date Issued: 2005
- Authors: Strelitz, Larry N
- Date: 2005
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159266 , vital:40282 , https://hdl.handle.net/10520/EJC146405
- Description: "African journalism" is a composite term, each element of which is problematic, and is open to differing interpretations. I'll deal with each in turn. An identity of any sort is always relational. Thus "Africa" and things "African" have meaning in relation to what is non-African - usually European or American.
- Full Text:
- Date Issued: 2005
The economic impact of Rhodes University students on the Grahamstown economy
- Snowball, Jeanette D, Antrobus, Geoffrey G
- Authors: Snowball, Jeanette D , Antrobus, Geoffrey G
- Date: 2005
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67475 , vital:29099
- Description: Publisher version , From Executive Summary: This study compares the spending patterns and economic impact of three groups of Rhodes University students: South Africans (SA), Other Africans and students from the Rest of the World (RoW). Data was collected via self-completion questionnaires and the final sample size was 163. Despite differences in spending patterns, total spending was found to be remarkably similar across groups, the major differences being between those students in university residence and those in digs (rented accommodation in town). Total monthly spending for those in residence was highest for SA students (R1034), then Other Africans (R850) and finally RoW (R777). For those in digs, total monthly spending was very similar, but again highest for SA students (R2495), then RoW (R2480) and then students from Other African countries (R2461). SA students have a considerably lower average unearned income than other groups, with students from the RoW having the highest unearned income (R1060 for those in residence and R2300 for those in digs). However, 55% of SA students, compared to 47% of foreign students, have sources of earned income, usually related to the university. Monthly income also tended to be higher for SA students (R654) than for other groups (Other Africa = R557; RoW = R575). The general conclusion that can be drawn is that there is very little difference in total spending between groups, although SA students have a somewhat higher average than others. A straight line ordinary least squares regression showed that, holding all else constant, SA students spent on average R169 more per month than foreign students (significant at the 10% level).
- Full Text:
- Date Issued: 2005
- Authors: Snowball, Jeanette D , Antrobus, Geoffrey G
- Date: 2005
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67475 , vital:29099
- Description: Publisher version , From Executive Summary: This study compares the spending patterns and economic impact of three groups of Rhodes University students: South Africans (SA), Other Africans and students from the Rest of the World (RoW). Data was collected via self-completion questionnaires and the final sample size was 163. Despite differences in spending patterns, total spending was found to be remarkably similar across groups, the major differences being between those students in university residence and those in digs (rented accommodation in town). Total monthly spending for those in residence was highest for SA students (R1034), then Other Africans (R850) and finally RoW (R777). For those in digs, total monthly spending was very similar, but again highest for SA students (R2495), then RoW (R2480) and then students from Other African countries (R2461). SA students have a considerably lower average unearned income than other groups, with students from the RoW having the highest unearned income (R1060 for those in residence and R2300 for those in digs). However, 55% of SA students, compared to 47% of foreign students, have sources of earned income, usually related to the university. Monthly income also tended to be higher for SA students (R654) than for other groups (Other Africa = R557; RoW = R575). The general conclusion that can be drawn is that there is very little difference in total spending between groups, although SA students have a somewhat higher average than others. A straight line ordinary least squares regression showed that, holding all else constant, SA students spent on average R169 more per month than foreign students (significant at the 10% level).
- Full Text:
- Date Issued: 2005
Five unpublished coins of Alexander the great and his successors in the Rhodes University collection
- Snowball, Jeanette D, Snowball, Warren D
- Authors: Snowball, Jeanette D , Snowball, Warren D
- Date: 2005
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70359 , vital:29648 , http://dx.doi.org/10.7445/50-0-73
- Description: The article briefly discusses the economic and political significance of the Alexander III(“the Great”) type silver tetradrachm and publishes three of his coins currently held by the Rhodes University Classics Museum. Based on stylistic elements, they are classified as from the Amphipolis and Arados mints and were probably minted during his lifetime. Two further tetradrachms from the empires of Alexander’s successors, Ptolemy II and Seleucus IV, are also published.
- Full Text:
- Date Issued: 2005
Five unpublished coins of Alexander the great and his successors in the Rhodes University collection
- Authors: Snowball, Jeanette D , Snowball, Warren D
- Date: 2005
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70359 , vital:29648 , http://dx.doi.org/10.7445/50-0-73
- Description: The article briefly discusses the economic and political significance of the Alexander III(“the Great”) type silver tetradrachm and publishes three of his coins currently held by the Rhodes University Classics Museum. Based on stylistic elements, they are classified as from the Amphipolis and Arados mints and were probably minted during his lifetime. Two further tetradrachms from the empires of Alexander’s successors, Ptolemy II and Seleucus IV, are also published.
- Full Text:
- Date Issued: 2005
Five unpublished coins of Alexander the Great and his successors in the Rhodes University Collection
- Snowball, Jeanette D, Snowball, Warren D
- Authors: Snowball, Jeanette D , Snowball, Warren D
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68489 , vital:29267 , http://dx.doi.org/10.7445/50-0-73
- Description: Publisher version , The article briefly discusses the economic and political significance of the Alexander III (“the Great”) type silver tetradrachm and publishes three of his coins currently held by the Rhodes University Classics Museum. Based on stylistic elements, they are classified as from the Amphipolis and Arados mints and were probably minted during his lifetime. Two further tetradrachms from the empires of Alexander’s successors, Ptolemy II and Seleucus IV, are also published.
- Full Text:
- Date Issued: 2012
Five unpublished coins of Alexander the Great and his successors in the Rhodes University Collection
- Authors: Snowball, Jeanette D , Snowball, Warren D
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68489 , vital:29267 , http://dx.doi.org/10.7445/50-0-73
- Description: Publisher version , The article briefly discusses the economic and political significance of the Alexander III (“the Great”) type silver tetradrachm and publishes three of his coins currently held by the Rhodes University Classics Museum. Based on stylistic elements, they are classified as from the Amphipolis and Arados mints and were probably minted during his lifetime. Two further tetradrachms from the empires of Alexander’s successors, Ptolemy II and Seleucus IV, are also published.
- Full Text:
- Date Issued: 2012
Lechwe Trust Collection:
- Authors: Simbao, Ruth K
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147547 , vital:38648 , https://doi.org/10.1162/afar.2005.38.3.78
- Description: The caustic humor of The Arts Delegate (2000), by the cartoonist popularly known in Zambia as" Yuss," captures a dynamic readily found in the Zambian art world.
- Full Text:
- Date Issued: 2013
- Authors: Simbao, Ruth K
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147547 , vital:38648 , https://doi.org/10.1162/afar.2005.38.3.78
- Description: The caustic humor of The Arts Delegate (2000), by the cartoonist popularly known in Zambia as" Yuss," captures a dynamic readily found in the Zambian art world.
- Full Text:
- Date Issued: 2013
Research on indigenous knowledge and its application: A case of wild food plants of Zimbabwe
- Authors: Shava, Soul
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/373809 , vital:66725 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122700"
- Description: Research on indigenous knowledge should go beyond documenting and interpreting it. Rather, it should stimulate inquiry into its application in present day community development and education settings. This study intends to steer indigenous knowledge research towards practical application initiatives. The study documents wild food plants of Zimbabwe, highlights some popular wild food plants, and cites some commercially marketed wild food plants and makes recommendations on the application of indigenous knowledge of wild food plants in community and educational settings.
- Full Text:
- Date Issued: 2005
- Authors: Shava, Soul
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/373809 , vital:66725 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122700"
- Description: Research on indigenous knowledge should go beyond documenting and interpreting it. Rather, it should stimulate inquiry into its application in present day community development and education settings. This study intends to steer indigenous knowledge research towards practical application initiatives. The study documents wild food plants of Zimbabwe, highlights some popular wild food plants, and cites some commercially marketed wild food plants and makes recommendations on the application of indigenous knowledge of wild food plants in community and educational settings.
- Full Text:
- Date Issued: 2005
Estimating the potential role of commercial over-harvesting in resource viability: A case study of five useful tree species in South Africa
- Shackleton, Charlie M, Guthrie, G, Main, R
- Authors: Shackleton, Charlie M , Guthrie, G , Main, R
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181324 , vital:43719 , xlink:href="https://doi.org/10.1002/ldr.652"
- Description: There is a growing commercialization of non-timber forest products (NTFPs) as a means of livelihood by rural communities throughout the developing world. This often occurs in the absence of any clear understanding of or guidelines regarding sustainable yields and ecological impacts, which may undermine the success of NTFP enterprises, especially from arid regions. This paper reports on the use of size class profiles and three quantitative indices to examine population profiles of five potentially useful tree species used as NTFPs in the semiarid lowveld of South Africa. We also contrast the population densities of the five tree species in 2003 with data from 1992. Low stem densities and population profiles indicated that three of the five species would preclude the establishment of NTFP enterprises based on their products. The other two species seem to have sufficient densities for some harvesting to take place, within an adaptive management framework. However, the longitudinal data indicated that the density of both these species had significantly declined over an eleven-year period, highlighting the need for appropriate management institutions. Additionally, the proportion of mature stems cut, and the degree of cutting per stem, had increased for all five species over the eleven years. The three quantitative indices of population stability were not correlated with one another, and hence provided a useful suite of measures sensitive to different aspects of size class profiles and their interpretation.
- Full Text:
- Date Issued: 2005
- Authors: Shackleton, Charlie M , Guthrie, G , Main, R
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181324 , vital:43719 , xlink:href="https://doi.org/10.1002/ldr.652"
- Description: There is a growing commercialization of non-timber forest products (NTFPs) as a means of livelihood by rural communities throughout the developing world. This often occurs in the absence of any clear understanding of or guidelines regarding sustainable yields and ecological impacts, which may undermine the success of NTFP enterprises, especially from arid regions. This paper reports on the use of size class profiles and three quantitative indices to examine population profiles of five potentially useful tree species used as NTFPs in the semiarid lowveld of South Africa. We also contrast the population densities of the five tree species in 2003 with data from 1992. Low stem densities and population profiles indicated that three of the five species would preclude the establishment of NTFP enterprises based on their products. The other two species seem to have sufficient densities for some harvesting to take place, within an adaptive management framework. However, the longitudinal data indicated that the density of both these species had significantly declined over an eleven-year period, highlighting the need for appropriate management institutions. Additionally, the proportion of mature stems cut, and the degree of cutting per stem, had increased for all five species over the eleven years. The three quantitative indices of population stability were not correlated with one another, and hence provided a useful suite of measures sensitive to different aspects of size class profiles and their interpretation.
- Full Text:
- Date Issued: 2005
The contribution and direct-use value of livestock to rural livelihoods in the Sand River catchment, South Africa
- Shackleton, Charlie M, Shackleton, Sheona E, Netshiluvhi, T R, Mathabela, F R
- Authors: Shackleton, Charlie M , Shackleton, Sheona E , Netshiluvhi, T R , Mathabela, F R
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181335 , vital:43720 , xlink:href="https://doi.org/10.2989/10220110509485870"
- Description: The productive functions of livestock ownership in communal areas are multipurpose in character, comprising a mix of stock types and a range of goods and services used. When all these multiple uses are accounted for, the cash and direct-use returns of livestock in communal areas can be comparable to commercial systems, although temporally and spatially variable. Yet previous work has generally excluded small stock from such analyses, as well as benefits and costs to non-owning households. This paper presents empirical results of a study in the Sand River catchment, assessing the benefits and costs accruing to owners and non-owners for both cattle and goats within a livelihoods analysis framework. Results indicate that cattle are used for a greater variety of goods and services than are goats. The savings value represented the most important function, followed by milk and then manure. Even if savings value was excluded, cattle ownership made a significant contribution to local livelihoods. Goats also provided a net positive benefit, represented largely by the savings value, followed by meat and cash sales. Non-owners also benefited through donations of manure, milk, draught and meat for free, or at a cheaper rate than alternatives. The majority of non-owners aspired to livestock ownership, although the risk of theft of animals was of growing concern. Averaged across the whole catchment, the net value of goods and services from livestock was just over R400 per hectare, with an annual return to capital of 36%. Cattle contributed the bulk of the value by virtue of their greater numbers and larger size, but on a per kilogramme basis goats provided higher value. Many of the goods and services obtained from livestock were not enumerated in regional or national economic statistics.
- Full Text:
- Date Issued: 2005
- Authors: Shackleton, Charlie M , Shackleton, Sheona E , Netshiluvhi, T R , Mathabela, F R
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181335 , vital:43720 , xlink:href="https://doi.org/10.2989/10220110509485870"
- Description: The productive functions of livestock ownership in communal areas are multipurpose in character, comprising a mix of stock types and a range of goods and services used. When all these multiple uses are accounted for, the cash and direct-use returns of livestock in communal areas can be comparable to commercial systems, although temporally and spatially variable. Yet previous work has generally excluded small stock from such analyses, as well as benefits and costs to non-owning households. This paper presents empirical results of a study in the Sand River catchment, assessing the benefits and costs accruing to owners and non-owners for both cattle and goats within a livelihoods analysis framework. Results indicate that cattle are used for a greater variety of goods and services than are goats. The savings value represented the most important function, followed by milk and then manure. Even if savings value was excluded, cattle ownership made a significant contribution to local livelihoods. Goats also provided a net positive benefit, represented largely by the savings value, followed by meat and cash sales. Non-owners also benefited through donations of manure, milk, draught and meat for free, or at a cheaper rate than alternatives. The majority of non-owners aspired to livestock ownership, although the risk of theft of animals was of growing concern. Averaged across the whole catchment, the net value of goods and services from livestock was just over R400 per hectare, with an annual return to capital of 36%. Cattle contributed the bulk of the value by virtue of their greater numbers and larger size, but on a per kilogramme basis goats provided higher value. Many of the goods and services obtained from livestock were not enumerated in regional or national economic statistics.
- Full Text:
- Date Issued: 2005
Growing of trees in home-gardens by rural households in the Eastern Cape and Limpopo Provinces, South Africa:
- Shackleton, Charlie M, Paumgarten, Fiona, Cocks, Michelle L
- Authors: Shackleton, Charlie M , Paumgarten, Fiona , Cocks, Michelle L
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141360 , vital:37965 , DOI: 10.1080/13504500509469647
- Description: Trees provide a wide range of goods and services to rural households which, when incorporated into their livelihood strategies, help reduce their vulnerability to adversity. Governments and policy makers often ignore the contribution made by trees and consequently resources are focussed on cash crops and livestock. Villagers in the Eastern Cape and Limpopo Province, South Africa utilise a range of trees from home-gardens for various purposes, although predominantly for fruit and shade. Trees are either planted or actively retained in households' home-gardens. There were noticeable differences between the villages in the Eastern Cape and those in Limpopo Province, particularly with respect to the overall density of trees per hectare and the number of species per household, both being significantly greater in Limpopo Province. The five most preferred species were listed for each village, revealing a preference for exotic fruit trees in Limpopo Province and a mix of exotic fruit trees and shade trees in the Eastern Cape. Households also retained useful indigenous species, predominantly fruit-bearing species. A range of factors constrain tree growing in home-gardens and households engage in practices to grow and maintain their trees. Not all of these constraints and practices were significantly different between the various localities.
- Full Text:
- Date Issued: 2009
- Authors: Shackleton, Charlie M , Paumgarten, Fiona , Cocks, Michelle L
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141360 , vital:37965 , DOI: 10.1080/13504500509469647
- Description: Trees provide a wide range of goods and services to rural households which, when incorporated into their livelihood strategies, help reduce their vulnerability to adversity. Governments and policy makers often ignore the contribution made by trees and consequently resources are focussed on cash crops and livestock. Villagers in the Eastern Cape and Limpopo Province, South Africa utilise a range of trees from home-gardens for various purposes, although predominantly for fruit and shade. Trees are either planted or actively retained in households' home-gardens. There were noticeable differences between the villages in the Eastern Cape and those in Limpopo Province, particularly with respect to the overall density of trees per hectare and the number of species per household, both being significantly greater in Limpopo Province. The five most preferred species were listed for each village, revealing a preference for exotic fruit trees in Limpopo Province and a mix of exotic fruit trees and shade trees in the Eastern Cape. Households also retained useful indigenous species, predominantly fruit-bearing species. A range of factors constrain tree growing in home-gardens and households engage in practices to grow and maintain their trees. Not all of these constraints and practices were significantly different between the various localities.
- Full Text:
- Date Issued: 2009
Synthesis, photophysicochemical studies of adjacently tetrasubstituted binaphthalo-phthalocyanines
- Seotsanyana-Mokhosi, Itumeleng, Chen, Ji-Yao, Nyokong, Tebello
- Authors: Seotsanyana-Mokhosi, Itumeleng , Chen, Ji-Yao , Nyokong, Tebello
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/289294 , vital:56616 , xlink:href="https://doi.org/10.1142/S108842460500040X"
- Description: Adjacent binaphthalo-phthalocyanines tetra-substituted with phenoxy (4a), 4-carboxyphenoxy (4b) and 4-t-butylphenoxy (4c) groups, as well as the di-substituted 4-carboxyphenoxy (5b) have been synthesized and characterized. The photophysical and photochemical behavior of 4a-c, were compared with those of the corresponding di-substituted derivatives, (5a-c). The secondary substituents on the phenoxy ring have an influence on the aggregation of the molecules and hence on their photophysical properties. All of the complexes exhibit a relatively good conversion of energy from the triplet-excited state to the singlet oxygen. The less aggregated molecule (4c), has the highest singlet oxygen quantum yield. For all the molecules, fluorescence yields are low and they all have relatively shorter triplet lifetimes compared with the unsubstituted zinc phthalocyanine. Increasing the number of ring substituents on these rigid MPc complexes (from complexes 5 to 4) showed a general increase in the triplet state lifetimes and singlet oxygen quantum yields, and a decrease in stability.
- Full Text:
- Date Issued: 2005
- Authors: Seotsanyana-Mokhosi, Itumeleng , Chen, Ji-Yao , Nyokong, Tebello
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/289294 , vital:56616 , xlink:href="https://doi.org/10.1142/S108842460500040X"
- Description: Adjacent binaphthalo-phthalocyanines tetra-substituted with phenoxy (4a), 4-carboxyphenoxy (4b) and 4-t-butylphenoxy (4c) groups, as well as the di-substituted 4-carboxyphenoxy (5b) have been synthesized and characterized. The photophysical and photochemical behavior of 4a-c, were compared with those of the corresponding di-substituted derivatives, (5a-c). The secondary substituents on the phenoxy ring have an influence on the aggregation of the molecules and hence on their photophysical properties. All of the complexes exhibit a relatively good conversion of energy from the triplet-excited state to the singlet oxygen. The less aggregated molecule (4c), has the highest singlet oxygen quantum yield. For all the molecules, fluorescence yields are low and they all have relatively shorter triplet lifetimes compared with the unsubstituted zinc phthalocyanine. Increasing the number of ring substituents on these rigid MPc complexes (from complexes 5 to 4) showed a general increase in the triplet state lifetimes and singlet oxygen quantum yields, and a decrease in stability.
- Full Text:
- Date Issued: 2005
Photophysical properties of a water-soluble adjacently substituted bisnaphthalophthalocyanine
- Seotsanyana-Mokhosi, Itumeleng, Nyokong, Tebello
- Authors: Seotsanyana-Mokhosi, Itumeleng , Nyokong, Tebello
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/286091 , vital:56237 , xlink:href="https://doi.org/10.1142/S1088424605000599"
- Description: Spectral properties of a water soluble metal free tetracarboxyphenoxy bisnaphthalo-phthalocyanine (3) were studied in water and organic solvents. It was found that in protic solvents, complex 3 was highly aggregated. The surfactant, Triton X100, and bovineserum albumin (BSA) do not effect disaggregation while cetyl trimethylammonium chloride (CTAC) caused the molecule to disaggregate. The fluorescence quantum yields were higher in the presence of CTAC. Studying the interaction of BSA with complex 3 using fluorometry revealed that BSA is highly quenched by the latter. A 1:1 stoichiometric binding ratio between BSA and the Pc was found. Triplet quantum yields in water containing CTAC were higher than in organic solvents.
- Full Text:
- Date Issued: 2005
- Authors: Seotsanyana-Mokhosi, Itumeleng , Nyokong, Tebello
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/286091 , vital:56237 , xlink:href="https://doi.org/10.1142/S1088424605000599"
- Description: Spectral properties of a water soluble metal free tetracarboxyphenoxy bisnaphthalo-phthalocyanine (3) were studied in water and organic solvents. It was found that in protic solvents, complex 3 was highly aggregated. The surfactant, Triton X100, and bovineserum albumin (BSA) do not effect disaggregation while cetyl trimethylammonium chloride (CTAC) caused the molecule to disaggregate. The fluorescence quantum yields were higher in the presence of CTAC. Studying the interaction of BSA with complex 3 using fluorometry revealed that BSA is highly quenched by the latter. A 1:1 stoichiometric binding ratio between BSA and the Pc was found. Triplet quantum yields in water containing CTAC were higher than in organic solvents.
- Full Text:
- Date Issued: 2005
Students’ Engagement with Learning Theory
- Authors: Schudel, Ingrid J
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/294436 , vital:57221
- Description: This paper reflects on a module on ‘Teaching and Learning Interactions’, presented as part of the Rhodes University Advanced Certificate in Education (Environmental Education).The module is designed to help students use theoretical logic to enhance (not replace) their practical logic of how teaching and learning takes place. Data was analysed from three teaching and learning activities in the module. After the first participatory activity on water and sanitation, students narrated what teaching and learning had taken place using language available from their prior experiences. In a second activity students were introduced to explanations of learning, provided by learning theorists. In the third activity students analysed a case study, using a variety of questions relating to teaching and learning. They then had to consider these same questions in the light of a participatory on-course teaching and learning activity. The paper reflects on how students have used understandings of the nature of reality, the construction of knowledge, the use of language, situated learning, action competence and social change, in order to narrate their teaching and learning experiences on the ACE(EE) course. Through this, the paper trials a reflexive approach to the teaching of learning theory in environmental education.
- Full Text:
- Date Issued: 2005
- Authors: Schudel, Ingrid J
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/294436 , vital:57221
- Description: This paper reflects on a module on ‘Teaching and Learning Interactions’, presented as part of the Rhodes University Advanced Certificate in Education (Environmental Education).The module is designed to help students use theoretical logic to enhance (not replace) their practical logic of how teaching and learning takes place. Data was analysed from three teaching and learning activities in the module. After the first participatory activity on water and sanitation, students narrated what teaching and learning had taken place using language available from their prior experiences. In a second activity students were introduced to explanations of learning, provided by learning theorists. In the third activity students analysed a case study, using a variety of questions relating to teaching and learning. They then had to consider these same questions in the light of a participatory on-course teaching and learning activity. The paper reflects on how students have used understandings of the nature of reality, the construction of knowledge, the use of language, situated learning, action competence and social change, in order to narrate their teaching and learning experiences on the ACE(EE) course. Through this, the paper trials a reflexive approach to the teaching of learning theory in environmental education.
- Full Text:
- Date Issued: 2005
Reproductive biology of ningu, Labeo victorianus (pisces: cyprinidae), in the kagera and Sio rivers, Uganda
- Rutaisire, Justus, Booth, Anthony J
- Authors: Rutaisire, Justus , Booth, Anthony J
- Date: 2005
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125864 , vital:35827 , https://doi.10.1007/s10641-004-5564-8
- Description: We investigated aspects of the reproductive biology of the cyprinid fish, Labeo victorianus, locally known as ningu, in the Kagera and Sio Rivers, Uganda. These rivers represent the last remaining refuges for this species within Uganda. L. victorianus is a highly fecund, potamodrometic fish that migrates upstream to spawn. Spawning is generally synchronised with the bimodal water level maxima observed within the rivers. There were, however, some deviations from this pattern. We caught sexually mature fish throughout the year in the Sio River, and noticed that spawing started before the second rainfall peak. Fish from the Kagera matured at significantly larger sizes than fish from the Sio River. Male and female fish, from both rivers, fed intensively during the non-breeding months accumulating significant fat reserves; a probable energy storage mechanism prior to their spawning migrations. The differences between the populations is probably a phenotypic response to differing abiotic factors such as river size, flow velocity and food availability.
- Full Text:
- Date Issued: 2005
- Authors: Rutaisire, Justus , Booth, Anthony J
- Date: 2005
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125864 , vital:35827 , https://doi.10.1007/s10641-004-5564-8
- Description: We investigated aspects of the reproductive biology of the cyprinid fish, Labeo victorianus, locally known as ningu, in the Kagera and Sio Rivers, Uganda. These rivers represent the last remaining refuges for this species within Uganda. L. victorianus is a highly fecund, potamodrometic fish that migrates upstream to spawn. Spawning is generally synchronised with the bimodal water level maxima observed within the rivers. There were, however, some deviations from this pattern. We caught sexually mature fish throughout the year in the Sio River, and noticed that spawing started before the second rainfall peak. Fish from the Kagera matured at significantly larger sizes than fish from the Sio River. Male and female fish, from both rivers, fed intensively during the non-breeding months accumulating significant fat reserves; a probable energy storage mechanism prior to their spawning migrations. The differences between the populations is probably a phenotypic response to differing abiotic factors such as river size, flow velocity and food availability.
- Full Text:
- Date Issued: 2005