The importance of long-term post-release studies in classical biological control: Insect–plant monitoring and public awareness of water hyacinth management (Pontederia crassipes) in Dique Los Sauces, Argentina
- Faltlhauser, Ana C, Jiménez, Nadia L, Righetti, Tomas, Visintin, Andrés M, Torrens, Javier, Salinas, Nicolás A, Mc Kay, Fernando, Hill, Martin P, Cordo, Hugo A, Sosa, Alejandro J
- Authors: Faltlhauser, Ana C , Jiménez, Nadia L , Righetti, Tomas , Visintin, Andrés M , Torrens, Javier , Salinas, Nicolás A , Mc Kay, Fernando , Hill, Martin P , Cordo, Hugo A , Sosa, Alejandro J
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/424828 , vital:72187 , xlink:href="https://doi.org/10.1111/eea.13355"
- Description: Several components of classical biological control (CBC) programmes are necessary to assess the success of the management strategy (e.g., post-release monitoring) and also help prevent reintroductions or resurgences of invasive species (e.g., public awareness). Water hyacinth, Pontederia (= Eichhornia) crassipes (Mart.) Solms (Pontederiaceae) is an aquatic plant naturally distributed in the north-eastern region of the Del Plata basin in Argentina. In the 1960s it was introduced into the Dique Los Sauces reservoir located outside of its native range in La Rioja Province, in western Argentina, where it became invasive. The natural enemy, Neochetina bruchi Hustache (Coleoptera: Curculionidae), was intentionally introduced in 1974 to control the weed. To assess the success of this CBC programme, a long-term post-release study was conducted. Between 1965 and 2023, we monitored plant coverage, estimated N. bruchi densities, and quantified the associated damage by reanalysing previously published data and incorporating new sampling. We also conducted an online survey to analyse public knowledge and perception about this programme. Water hyacinth coverage fluctuated from its first record in 1965 (maximum coverage 90%) until the control of germinated plants (coverage 0%) in 2018. The plant decline was accompanied by an increase in the weevil population. In our survey, out of 325 respondents only a small group of mostly middle-aged and elderly people knew that the restoration had been achieved through a management strategy and even fewer were aware of the biocontrol approach taken. Respondents who had a positive approach to biological control were more aware of the management plan than respondents who had neutral or negative opinions. Neochetina bruchi has played a key factor in the control of P. crassipes. The intrinsic dynamics of these populations, the dormant seed bank, and the lack of public awareness support the need for long post-release evaluations including outreach campaigns to make a sustainable successful management programme.
- Full Text:
- Date Issued: 2023
- Authors: Faltlhauser, Ana C , Jiménez, Nadia L , Righetti, Tomas , Visintin, Andrés M , Torrens, Javier , Salinas, Nicolás A , Mc Kay, Fernando , Hill, Martin P , Cordo, Hugo A , Sosa, Alejandro J
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/424828 , vital:72187 , xlink:href="https://doi.org/10.1111/eea.13355"
- Description: Several components of classical biological control (CBC) programmes are necessary to assess the success of the management strategy (e.g., post-release monitoring) and also help prevent reintroductions or resurgences of invasive species (e.g., public awareness). Water hyacinth, Pontederia (= Eichhornia) crassipes (Mart.) Solms (Pontederiaceae) is an aquatic plant naturally distributed in the north-eastern region of the Del Plata basin in Argentina. In the 1960s it was introduced into the Dique Los Sauces reservoir located outside of its native range in La Rioja Province, in western Argentina, where it became invasive. The natural enemy, Neochetina bruchi Hustache (Coleoptera: Curculionidae), was intentionally introduced in 1974 to control the weed. To assess the success of this CBC programme, a long-term post-release study was conducted. Between 1965 and 2023, we monitored plant coverage, estimated N. bruchi densities, and quantified the associated damage by reanalysing previously published data and incorporating new sampling. We also conducted an online survey to analyse public knowledge and perception about this programme. Water hyacinth coverage fluctuated from its first record in 1965 (maximum coverage 90%) until the control of germinated plants (coverage 0%) in 2018. The plant decline was accompanied by an increase in the weevil population. In our survey, out of 325 respondents only a small group of mostly middle-aged and elderly people knew that the restoration had been achieved through a management strategy and even fewer were aware of the biocontrol approach taken. Respondents who had a positive approach to biological control were more aware of the management plan than respondents who had neutral or negative opinions. Neochetina bruchi has played a key factor in the control of P. crassipes. The intrinsic dynamics of these populations, the dormant seed bank, and the lack of public awareness support the need for long post-release evaluations including outreach campaigns to make a sustainable successful management programme.
- Full Text:
- Date Issued: 2023
Shifting contexts: contemporary South African art in changing times
- Authors: Ntombela, N
- Date: 2019
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/146200 , vital:38504 , ISBN 9781869143398 , https://books.google.co.za/books?id=xZlAjySD5-cCandq=Tribing+and+Untribing+the+Archive:+Identity+and+the+Material+Record+in+Southern+KwaZulu-Natal+in+the+Late+Independent+and+Colonial+Periodsdq=Tribing+and+Untribing+the+Archive:+Identity+and+the+Material+Record+in+Southern+KwaZulu-Natal+in+the+Late+Independent+and+Colonial+Periodsl=ensa=Xved=0ahUKEwjJ3oOGgcDpAhVuURUIHQyoAnIQ6AEIJzAA
- Description: Book abstract. The pernicious combination of tribe and tradition continues to tether modern South Africans to ideas about the region's remote past as primitive, timeless, and unchanging. Any hunger for knowledge or understanding of the past before European colonialism remains to a significant degree unsated in the face of a narrowly prescribed archive and repugnant, but insidiously resilient, stereotypes. These volumes track how the domain of the tribal and traditional came to be sharply distinguished from modernity, how it was denied a changing history and an archive, and was endowed instead with a timeless culture. They also offer strategies for engaging with the materials differently-from the interventions effected in contemporary artworks to the inserting of nameless, timeless objects of material culture into histories of individualized and politicized experience. The two volume set make this archive of material culture visible as an archival resource. They also seek to spring the identity trap, releasing the material from pre-assigned identity positions as tribal into settings that enable them to be used as resources for thinking critically about identity.
- Full Text:
- Date Issued: 2019
- Authors: Ntombela, N
- Date: 2019
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/146200 , vital:38504 , ISBN 9781869143398 , https://books.google.co.za/books?id=xZlAjySD5-cCandq=Tribing+and+Untribing+the+Archive:+Identity+and+the+Material+Record+in+Southern+KwaZulu-Natal+in+the+Late+Independent+and+Colonial+Periodsdq=Tribing+and+Untribing+the+Archive:+Identity+and+the+Material+Record+in+Southern+KwaZulu-Natal+in+the+Late+Independent+and+Colonial+Periodsl=ensa=Xved=0ahUKEwjJ3oOGgcDpAhVuURUIHQyoAnIQ6AEIJzAA
- Description: Book abstract. The pernicious combination of tribe and tradition continues to tether modern South Africans to ideas about the region's remote past as primitive, timeless, and unchanging. Any hunger for knowledge or understanding of the past before European colonialism remains to a significant degree unsated in the face of a narrowly prescribed archive and repugnant, but insidiously resilient, stereotypes. These volumes track how the domain of the tribal and traditional came to be sharply distinguished from modernity, how it was denied a changing history and an archive, and was endowed instead with a timeless culture. They also offer strategies for engaging with the materials differently-from the interventions effected in contemporary artworks to the inserting of nameless, timeless objects of material culture into histories of individualized and politicized experience. The two volume set make this archive of material culture visible as an archival resource. They also seek to spring the identity trap, releasing the material from pre-assigned identity positions as tribal into settings that enable them to be used as resources for thinking critically about identity.
- Full Text:
- Date Issued: 2019
Colonised minds?: post-development theory and the desirability of development in Africa
- Authors: Matthews, Sally
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142213 , vital:38059 , DOI: 10.1080/01436597.2017.1279540
- Description: While post-development theory is very concerned with the ways in which development has impacted upon the countries of the Global South, there has been relatively little written on post-development theory from an African perspective. This paper identifies some of the ways in which post-development theory fails to adequately understand the African experience of development. In particular, I explore the difficulty that post-development theory confronts when faced with the continued desire on the part of many people in Africa for development.
- Full Text:
- Date Issued: 2017
- Authors: Matthews, Sally
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142213 , vital:38059 , DOI: 10.1080/01436597.2017.1279540
- Description: While post-development theory is very concerned with the ways in which development has impacted upon the countries of the Global South, there has been relatively little written on post-development theory from an African perspective. This paper identifies some of the ways in which post-development theory fails to adequately understand the African experience of development. In particular, I explore the difficulty that post-development theory confronts when faced with the continued desire on the part of many people in Africa for development.
- Full Text:
- Date Issued: 2017
Counting on demographic equity to transform institutional cultures at historically white South African universities?:
- Booi, Masixole, Vincent, Louise, Liccardo, Sabrina
- Authors: Booi, Masixole , Vincent, Louise , Liccardo, Sabrina
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141946 , vital:38018 , DOI: 10.1080/07294360.2017.1289155
- Description: The post-apartheid higher education transformation project is faced with the challenge of recruiting and retaining black academics and other senior staff. But when we shift the focus from participation rates to equality–inequality within historically white universities (HWUs), then the discourse changes from demographic equity and redress to institutional culture and diversity. HWUs invoke the need to maintain their position as leading higher education institutions globally, and notions of ‘quality’ and ‘excellence’ have emerged as discursive practices, which serve to perpetuate exclusion. The question then arises as to which forms of capital comprise the Gold Standard at HWUs? Several South African universities have responded to the challenge of recruiting and retaining black academics by initiating programmes for the ‘accelerated development’ of these candidates.
- Full Text:
- Date Issued: 2017
- Authors: Booi, Masixole , Vincent, Louise , Liccardo, Sabrina
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141946 , vital:38018 , DOI: 10.1080/07294360.2017.1289155
- Description: The post-apartheid higher education transformation project is faced with the challenge of recruiting and retaining black academics and other senior staff. But when we shift the focus from participation rates to equality–inequality within historically white universities (HWUs), then the discourse changes from demographic equity and redress to institutional culture and diversity. HWUs invoke the need to maintain their position as leading higher education institutions globally, and notions of ‘quality’ and ‘excellence’ have emerged as discursive practices, which serve to perpetuate exclusion. The question then arises as to which forms of capital comprise the Gold Standard at HWUs? Several South African universities have responded to the challenge of recruiting and retaining black academics by initiating programmes for the ‘accelerated development’ of these candidates.
- Full Text:
- Date Issued: 2017
Decoupled reciprocal subsidies of biomass and fatty acids in fluxes of invertebrates between a temperate river and the adjacent land:
- Moyo, Sydney, Chari, Lenin D, Villet, Martin H, Richoux, Nicole B
- Authors: Moyo, Sydney , Chari, Lenin D , Villet, Martin H , Richoux, Nicole B
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/140843 , vital:37923 , DOI: 10.1007/s00027-017-0529-0
- Description: Streams and riparian areas are tightly coupled through reciprocal trophic subsidies, and there is evidence that these subsidies affect consumers in connected ecosystems. Most studies of subsidies consider only their quantity and not their quality. We determined the bidirectional exchange of organisms between the Kowie River and its riparian zone in South Africa using floating pyramidal traps (to measure insect emergence) and pan traps (to capture infalling invertebrates).
- Full Text:
- Date Issued: 2017
- Authors: Moyo, Sydney , Chari, Lenin D , Villet, Martin H , Richoux, Nicole B
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/140843 , vital:37923 , DOI: 10.1007/s00027-017-0529-0
- Description: Streams and riparian areas are tightly coupled through reciprocal trophic subsidies, and there is evidence that these subsidies affect consumers in connected ecosystems. Most studies of subsidies consider only their quantity and not their quality. We determined the bidirectional exchange of organisms between the Kowie River and its riparian zone in South Africa using floating pyramidal traps (to measure insect emergence) and pan traps (to capture infalling invertebrates).
- Full Text:
- Date Issued: 2017
Forensic entomotoxicology revisited: towards professional standardisation of study designs
- da Silva, Erica I T, Wilhelmi, Brendan S, Villet, Martin H
- Authors: da Silva, Erica I T , Wilhelmi, Brendan S , Villet, Martin H
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/140819 , vital:37921 , DOI: 10.1007/s00414-017-1603-9
- Description: Forensic entomotoxicology is the use of insects as evidence of whether a toxicant is present in an environment such as a corpse, river or landscape. The earliest overtly forensic study was published in 1977, and since then, at least 63 papers have been published, most of them focused on the detection of toxicants in insects or on effects of toxicants on diverse insect indicator taxa. A comprehensive review of the published literature revealed various inconsistencies between studies that could be addressed by introducing standard protocols for such studies. These protocols could include selecting widespread and common model organisms (such as Lucilia sericata, Calliphora vicina, Chrysomya megacephala and Dermestes maculatus) and model toxicants (e.g. morphine and amitriptyline) to build up comparative databases; developing a standard matrix for use as a feeding substrate; setting guidelines for statistically adequate sample sizes; and deploying more sophisticated analytical methods from the general field of toxicology.
- Full Text:
- Date Issued: 2017
- Authors: da Silva, Erica I T , Wilhelmi, Brendan S , Villet, Martin H
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/140819 , vital:37921 , DOI: 10.1007/s00414-017-1603-9
- Description: Forensic entomotoxicology is the use of insects as evidence of whether a toxicant is present in an environment such as a corpse, river or landscape. The earliest overtly forensic study was published in 1977, and since then, at least 63 papers have been published, most of them focused on the detection of toxicants in insects or on effects of toxicants on diverse insect indicator taxa. A comprehensive review of the published literature revealed various inconsistencies between studies that could be addressed by introducing standard protocols for such studies. These protocols could include selecting widespread and common model organisms (such as Lucilia sericata, Calliphora vicina, Chrysomya megacephala and Dermestes maculatus) and model toxicants (e.g. morphine and amitriptyline) to build up comparative databases; developing a standard matrix for use as a feeding substrate; setting guidelines for statistically adequate sample sizes; and deploying more sophisticated analytical methods from the general field of toxicology.
- Full Text:
- Date Issued: 2017
MD-TASK: a software suite for analyzing molecular dynamics trajectories
- Brown, David K, Penkler, David L, Amamuddy, Olivier S, Ross, Caroline J, Atilgan, Ali R, Atilgan, Canan, Tastan Bishop, Özlem
- Authors: Brown, David K , Penkler, David L , Amamuddy, Olivier S , Ross, Caroline J , Atilgan, Ali R , Atilgan, Canan , Tastan Bishop, Özlem
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125138 , vital:35735 , https://doi.10.1093/bioinformatics/btx349
- Description: Molecular dynamics (MD) determines the physical motions of atoms of a biological macromolecule in a cell-like environment and is an important method in structural bioinformatics. Traditionally, measurements such as root mean square deviation, root mean square fluctuation, radius of gyration, and various energy measures have been used to analyze MD simulations. Here, we present MD-TASK, a novel software suite that employs graph theory techniques, perturbation response scanning, and dynamic cross-correlation to provide unique ways for analyzing MD trajectories.
- Full Text:
- Date Issued: 2017
- Authors: Brown, David K , Penkler, David L , Amamuddy, Olivier S , Ross, Caroline J , Atilgan, Ali R , Atilgan, Canan , Tastan Bishop, Özlem
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125138 , vital:35735 , https://doi.10.1093/bioinformatics/btx349
- Description: Molecular dynamics (MD) determines the physical motions of atoms of a biological macromolecule in a cell-like environment and is an important method in structural bioinformatics. Traditionally, measurements such as root mean square deviation, root mean square fluctuation, radius of gyration, and various energy measures have been used to analyze MD simulations. Here, we present MD-TASK, a novel software suite that employs graph theory techniques, perturbation response scanning, and dynamic cross-correlation to provide unique ways for analyzing MD trajectories.
- Full Text:
- Date Issued: 2017
Pessimistic assessment of white shark population status in South Africa: comment on Andreotti et al.(2016)
- Irion, Dylan T, Noble, Leslie R, Kock, Alison A, Gennari, Enrico, Dicken, Matthew L, Hewitt, Adrian M, Towner, Alison V, Booth, Anthony J, Smale, Malcolm J, Cliff, Geremy
- Authors: Irion, Dylan T , Noble, Leslie R , Kock, Alison A , Gennari, Enrico , Dicken, Matthew L , Hewitt, Adrian M , Towner, Alison V , Booth, Anthony J , Smale, Malcolm J , Cliff, Geremy
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/${Handle} , vital:35799 , https://doi.10.3354/meps12283
- Description: Andreotti et al. (2016; Mar Ecol Prog Ser 552:241−253) estimate an abundance (N) of 438 white sharks Carcharodon carcharias and a contemporary effective population size (CNe) of 333 individuals along the South African coast. N was estimated by using a mark-recapture analysis of photographic identification records from a single aggregation site (Gansbaai). CNe was calculated based on the levels of pairwise linkage disequilibrium of genetic material collected from 4 aggregation sites across approximately 965 km of South African coastline. However, due to the complex stock structure of white sharks and the model assumptions made by Andreotti et al. (2016), the conclusions drawn cannot be supported by their methods and data.
- Full Text:
- Date Issued: 2017
- Authors: Irion, Dylan T , Noble, Leslie R , Kock, Alison A , Gennari, Enrico , Dicken, Matthew L , Hewitt, Adrian M , Towner, Alison V , Booth, Anthony J , Smale, Malcolm J , Cliff, Geremy
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/${Handle} , vital:35799 , https://doi.10.3354/meps12283
- Description: Andreotti et al. (2016; Mar Ecol Prog Ser 552:241−253) estimate an abundance (N) of 438 white sharks Carcharodon carcharias and a contemporary effective population size (CNe) of 333 individuals along the South African coast. N was estimated by using a mark-recapture analysis of photographic identification records from a single aggregation site (Gansbaai). CNe was calculated based on the levels of pairwise linkage disequilibrium of genetic material collected from 4 aggregation sites across approximately 965 km of South African coastline. However, due to the complex stock structure of white sharks and the model assumptions made by Andreotti et al. (2016), the conclusions drawn cannot be supported by their methods and data.
- Full Text:
- Date Issued: 2017
Rhodes University Graduation Ceremony 2017
- Authors: Rhodes University
- Date: 2017
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/58067 , vital:27061
- Description: 2017 Graduation Ceremony, Umsitho Wothweso-Zidanga, Gradeplegtigheid [at] 1820 Settlers National Monument, Thursday, 20 April until Saturday, 22 April 2017.
- Full Text:
- Date Issued: 2017
- Authors: Rhodes University
- Date: 2017
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/58067 , vital:27061
- Description: 2017 Graduation Ceremony, Umsitho Wothweso-Zidanga, Gradeplegtigheid [at] 1820 Settlers National Monument, Thursday, 20 April until Saturday, 22 April 2017.
- Full Text:
- Date Issued: 2017
Synthesis, characterisation and evaluation of benzoxaborole-based hybrids as antiplasmodial agents
- Authors: Gumbo, Maureen
- Date: 2017
- Subjects: Malaria Chemotherapy , Antimalarials , Boron compounds , Drug resistance , Plasmodium falciparum , Drug development
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/59193 , vital:27456
- Description: Malaria is a mosquito-borne disease, which continues to pose a threat to the entire humanity. About 40% of the world population is estimated to be at risk of infections by malaria. Despite efforts undertaken by scientific community, government entities and international organizations, malaria is still rampant. The major problem is drug resistance, where the Plasmodium spp have over the past decades developed drug resistance against available drugs. In order to counter this problem, novel antimalarial drugs that are efficacious and with novel mode of action are of great necessity. Benzoxaborole derivatives have been shown to exhibit promising antimalarial activity against Plasmodium falciparum strains. Previous studies reported on the compounds such as 6-(2- (alkoxycarbonyl)pyrazinyl-5-oxy)-1,3-dihydro-1-hydroxy-2,1-benzoxaboroles, which showed good antimalarial activity against both W7 and 3D7 strains without significant toxicity. On the other hand, chloroquine (CQ) and cinnamic acids have a wide variety of biological activity including antimalarial activity. Herein, a hybridisation strategy was employed to synthesise new CQ-benzoxaborole and cinnamoyl-benzoxaborole hybrids. CQ-Benzoxaborole 2.12a-c and cinnamoylbenzoxaborole 2.11a-g hydrid molecules were synthesised in low to good yields. Their structural identities were confirmed using conventional spectroscopic techniques (1H and 13C NMR, and mass spectrometry). CQ-benzoxaborole compounds, however, showed instability, and only 2.12b was used for in vitro biological assay and showed activity comparable to CQ. Furthermore, in vitro biological assay revealed that compounds 2.11a-g poorly inhibited the growth of P. falciparum parasites. Interestingly, these compounds, however, exhibited satisfactory activity against Trypanosoma brucei with IC50 = 0.052 μM for compound 2.11g. The cell cytotoxicity assay of all final compounds confirmed that all CQ-benzoxaborole 2.12b and cinnamoyl-benzoxaborole 2.11a-g hybrids were non-toxic against HeLa cell lines. However, efforts to further expand the structure-activity relationship (SAR) of CQbenzoxaborole by increasing the length of the linker with one extra carbon (Scheme 2.10) were not possible as an important precursor 6-formylbenzoxaborole 2.29 could not be synthesized in sufficient yields. , Thesis (MSc) -- Faculty of Faculty of Science, Chemistry, 2017
- Full Text:
- Date Issued: 2017
- Authors: Gumbo, Maureen
- Date: 2017
- Subjects: Malaria Chemotherapy , Antimalarials , Boron compounds , Drug resistance , Plasmodium falciparum , Drug development
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/59193 , vital:27456
- Description: Malaria is a mosquito-borne disease, which continues to pose a threat to the entire humanity. About 40% of the world population is estimated to be at risk of infections by malaria. Despite efforts undertaken by scientific community, government entities and international organizations, malaria is still rampant. The major problem is drug resistance, where the Plasmodium spp have over the past decades developed drug resistance against available drugs. In order to counter this problem, novel antimalarial drugs that are efficacious and with novel mode of action are of great necessity. Benzoxaborole derivatives have been shown to exhibit promising antimalarial activity against Plasmodium falciparum strains. Previous studies reported on the compounds such as 6-(2- (alkoxycarbonyl)pyrazinyl-5-oxy)-1,3-dihydro-1-hydroxy-2,1-benzoxaboroles, which showed good antimalarial activity against both W7 and 3D7 strains without significant toxicity. On the other hand, chloroquine (CQ) and cinnamic acids have a wide variety of biological activity including antimalarial activity. Herein, a hybridisation strategy was employed to synthesise new CQ-benzoxaborole and cinnamoyl-benzoxaborole hybrids. CQ-Benzoxaborole 2.12a-c and cinnamoylbenzoxaborole 2.11a-g hydrid molecules were synthesised in low to good yields. Their structural identities were confirmed using conventional spectroscopic techniques (1H and 13C NMR, and mass spectrometry). CQ-benzoxaborole compounds, however, showed instability, and only 2.12b was used for in vitro biological assay and showed activity comparable to CQ. Furthermore, in vitro biological assay revealed that compounds 2.11a-g poorly inhibited the growth of P. falciparum parasites. Interestingly, these compounds, however, exhibited satisfactory activity against Trypanosoma brucei with IC50 = 0.052 μM for compound 2.11g. The cell cytotoxicity assay of all final compounds confirmed that all CQ-benzoxaborole 2.12b and cinnamoyl-benzoxaborole 2.11a-g hybrids were non-toxic against HeLa cell lines. However, efforts to further expand the structure-activity relationship (SAR) of CQbenzoxaborole by increasing the length of the linker with one extra carbon (Scheme 2.10) were not possible as an important precursor 6-formylbenzoxaborole 2.29 could not be synthesized in sufficient yields. , Thesis (MSc) -- Faculty of Faculty of Science, Chemistry, 2017
- Full Text:
- Date Issued: 2017
"Let loose in the unthinkable unspeakable": waiting and alterity in Samuel Beckett's trilogy
- Authors: Marais, Jessica
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/3917 , vital:20557
- Description: In this thesis, I examine the interrelated roles of waiting and alterity in Samuel Beckett's trilogy of novels: Molloy, Malone Dies and The Unnamable. The conventional understanding of waiting is as an intentional relationship between a waiting subject and an awaited object. This kind of waiting is end-directed, and, in order for it to be worthwhile, the awaited must, at some point, arrive. In the trilogy, however, the awaited never does arrive, and it is my contention that the novels are concerned with an unconventional kind of waiting, which, being without object or end, takes the form of a non-intentional relationship between waiter and awaited. Significantly, through the non-intentional wait, the subject awaits the unawaited. She or he thereby encounters the radically other, or that which cannot be rendered familiar or assimilated in any way – an unthinkable, unspeakable, ungraspable excess that overflows the limits of thought and language. The texts foreground the vexed question of response to such alterity: how can one approach the ungraspable as ungraspable, when it is in the nature of any approach to attempt to grasp? I argue that the texts explore a paradoxical form of "incurious seeking" as an avenue to accommodate the absolutely other.
- Full Text:
- Date Issued: 2016
- Authors: Marais, Jessica
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/3917 , vital:20557
- Description: In this thesis, I examine the interrelated roles of waiting and alterity in Samuel Beckett's trilogy of novels: Molloy, Malone Dies and The Unnamable. The conventional understanding of waiting is as an intentional relationship between a waiting subject and an awaited object. This kind of waiting is end-directed, and, in order for it to be worthwhile, the awaited must, at some point, arrive. In the trilogy, however, the awaited never does arrive, and it is my contention that the novels are concerned with an unconventional kind of waiting, which, being without object or end, takes the form of a non-intentional relationship between waiter and awaited. Significantly, through the non-intentional wait, the subject awaits the unawaited. She or he thereby encounters the radically other, or that which cannot be rendered familiar or assimilated in any way – an unthinkable, unspeakable, ungraspable excess that overflows the limits of thought and language. The texts foreground the vexed question of response to such alterity: how can one approach the ungraspable as ungraspable, when it is in the nature of any approach to attempt to grasp? I argue that the texts explore a paradoxical form of "incurious seeking" as an avenue to accommodate the absolutely other.
- Full Text:
- Date Issued: 2016
A bitcoin framework : an alternative payment system for marginalized areas of South Africa using low-end mobile phones
- Authors: Dlamini, Nelisiwe Peaceness
- Date: 2016
- Subjects: Electronic funds transfers -- South Africa Bitcoin -- South Africa Mobile commerce -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11884 , vital:39115
- Description: The emergence of the cryptocurrency Bitcoin, has invoked the need for developing financial systems that can be used to transfer digital value. This would serve as a solution to developing countries especially the challenged ones, when it comes to accommodating the financial needs of the disadvantaged people. Moreover, it facilitates access to financial services to allow them to transact with ease. Numerous companies have taken advantage of the prevalence of mobile phones and introduced financial platforms to provide financial inclusion to disadvantaged people. Financial institutions and Mobile Network Operators (MNO) have developed platforms such as cell phone banking services, mobile money, mobile wallets, and electronic wallets that can be used to provide affordable financial services. Although this is the case, alternative platforms that are affordable and accessible through mobile phones are still required. Therefore, this study proposes a Bitcoin framework that can be used as an alternative platform through low-end mobile phones to provide access to financial services to the disadvantaged people in marginalized areas. To prove the concept of the proposed Bitcoin framework, a Mobile Bitcoin Wallet System (MBWS) prototype was developed, which allows a person using a low-end mobile phone with no intervening technology such as Internet or Bluetooth, to access a Bitcoin wallet by sending a Short Message Service (SMS). This enables Bitcoin to be accessed more easily and affordably by the people. Thus the developed prototype conceptualizes an alternative payment system or a payment method that can augment the existing payment methods. The MBWS is evaluated to assess if it can offer the services that other platforms offer by being compared to a cell-phone banking service. It was deployed on a computer connected to the Internet to enable a connection to the Bitcoin network and access to the blockchain which records all the transactions that take place in Bitcoin. Although this system provides access to the Bitcoin wallet, for it to be applied to areas where people require an alternative payment system, it still needs to be enhanced for such use. This includes scaling the system and adding more functions to it.
- Full Text:
- Date Issued: 2016
- Authors: Dlamini, Nelisiwe Peaceness
- Date: 2016
- Subjects: Electronic funds transfers -- South Africa Bitcoin -- South Africa Mobile commerce -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11884 , vital:39115
- Description: The emergence of the cryptocurrency Bitcoin, has invoked the need for developing financial systems that can be used to transfer digital value. This would serve as a solution to developing countries especially the challenged ones, when it comes to accommodating the financial needs of the disadvantaged people. Moreover, it facilitates access to financial services to allow them to transact with ease. Numerous companies have taken advantage of the prevalence of mobile phones and introduced financial platforms to provide financial inclusion to disadvantaged people. Financial institutions and Mobile Network Operators (MNO) have developed platforms such as cell phone banking services, mobile money, mobile wallets, and electronic wallets that can be used to provide affordable financial services. Although this is the case, alternative platforms that are affordable and accessible through mobile phones are still required. Therefore, this study proposes a Bitcoin framework that can be used as an alternative platform through low-end mobile phones to provide access to financial services to the disadvantaged people in marginalized areas. To prove the concept of the proposed Bitcoin framework, a Mobile Bitcoin Wallet System (MBWS) prototype was developed, which allows a person using a low-end mobile phone with no intervening technology such as Internet or Bluetooth, to access a Bitcoin wallet by sending a Short Message Service (SMS). This enables Bitcoin to be accessed more easily and affordably by the people. Thus the developed prototype conceptualizes an alternative payment system or a payment method that can augment the existing payment methods. The MBWS is evaluated to assess if it can offer the services that other platforms offer by being compared to a cell-phone banking service. It was deployed on a computer connected to the Internet to enable a connection to the Bitcoin network and access to the blockchain which records all the transactions that take place in Bitcoin. Although this system provides access to the Bitcoin wallet, for it to be applied to areas where people require an alternative payment system, it still needs to be enhanced for such use. This includes scaling the system and adding more functions to it.
- Full Text:
- Date Issued: 2016
A business intelligence framework for supporting strategic sustainability information management in higher education
- Authors: Haupt, Ross
- Date: 2016
- Subjects: Business intelligence , Strategic planning -- Management
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10948/5319 , vital:20832
- Description: In the higher education sector, a number of Higher Education Institutions (HEIs) are playing a leading role in promoting sustainable initiatives. Effectively managing these initiatives however can be a complex task and requires data and information from multiple aspects of operations. In an HEI, operating sustainably means ensuring financial sustainability, social sustainability, environmental sustainability and educational sustainability. In order to manage sustainability effectively, HEIs require an integrated tool that can provide information on all areas of sustainability. HEIs face a number of challenges in effectively managing sustainability information, such as siloed data and information, and poor sharing and communication of information. Business Intelligence (BI) can assist in overcoming many of the challenges faced by organisations in effectively managing strategic sustainability information. This study investigates both the constraints to effective sustainability information management and the challenges of BI. A BI framework to support effective strategic sustainability information management is proposed. Nelson Mandela Metropolitan University (NMMU) is one such HEI, which is affected by the challenges of managing strategic sustainability information. NMMU is therefore used as a case study in this research. A BI solution, Sustainable BI, was developed based on the proposed framework. The main goal of sustainable BI is to provide strategic management at NMMU with a tool that can provide integrated sustainability information that can assist in overcoming the challenges in effectively managing strategic sustainability information. Sustainable BI was evaluated by strategic management at NMMU who are responsible for managing sustainability at NMMU. The evaluation took place through a usability study. The study revealed to what extent Sustainable BI could effectively manage strategic sustainability information at NMMU. The BI framework was iteratively improved on based on the results of the evaluations. The contributions from this study are a model for sustainability management, a BI Framework to support strategic sustainability information management and a BI solution, Sustainable BI.
- Full Text:
- Date Issued: 2016
- Authors: Haupt, Ross
- Date: 2016
- Subjects: Business intelligence , Strategic planning -- Management
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10948/5319 , vital:20832
- Description: In the higher education sector, a number of Higher Education Institutions (HEIs) are playing a leading role in promoting sustainable initiatives. Effectively managing these initiatives however can be a complex task and requires data and information from multiple aspects of operations. In an HEI, operating sustainably means ensuring financial sustainability, social sustainability, environmental sustainability and educational sustainability. In order to manage sustainability effectively, HEIs require an integrated tool that can provide information on all areas of sustainability. HEIs face a number of challenges in effectively managing sustainability information, such as siloed data and information, and poor sharing and communication of information. Business Intelligence (BI) can assist in overcoming many of the challenges faced by organisations in effectively managing strategic sustainability information. This study investigates both the constraints to effective sustainability information management and the challenges of BI. A BI framework to support effective strategic sustainability information management is proposed. Nelson Mandela Metropolitan University (NMMU) is one such HEI, which is affected by the challenges of managing strategic sustainability information. NMMU is therefore used as a case study in this research. A BI solution, Sustainable BI, was developed based on the proposed framework. The main goal of sustainable BI is to provide strategic management at NMMU with a tool that can provide integrated sustainability information that can assist in overcoming the challenges in effectively managing strategic sustainability information. Sustainable BI was evaluated by strategic management at NMMU who are responsible for managing sustainability at NMMU. The evaluation took place through a usability study. The study revealed to what extent Sustainable BI could effectively manage strategic sustainability information at NMMU. The BI framework was iteratively improved on based on the results of the evaluations. The contributions from this study are a model for sustainability management, a BI Framework to support strategic sustainability information management and a BI solution, Sustainable BI.
- Full Text:
- Date Issued: 2016
A case for contemporary third literature: the black experience in the postmillennial fiction of three Kwela authors
- Authors: Mthembu, Lumumba
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/3322 , vital:20480
- Description: This study seeks to uncover the manner in which the young black experience is constructed in three novels by Sifiso Mzobe, Kgebetli Moele and K. Sello Duiker. Young Blood, Untitled and Thirteen Cents all feature teenage narrators navigating the social milieu of South Africa in the twenty-first century. My analysis is informed by Frantz Fanon’s postcolonial theory because South Africa’s socio-economic landscape conforms to the divisions laid out in The Wretched of the Earth. I contend that post-apartheid South Africa is developing in a manner that is symptomatic of the Fanonian post-independence African state. My close reading of the novels teases out the conditions under which young black subjects must survive and express themselves. I look into the roles of the community, the government, the family, and the school in shaping this experience. Naturally, my discussion segues into questions of sexuality and gender as they intersect with race. I demonstrate how these texts fail and succeed as works of Third Literature, a genre derived from Third Cinema, which I have adapted due to its Fanonian ideological underpinning. Third Literature is a fundamentally revolutionary and activistic genre which seeks to pave the way for social change. In this regard, I concern myself with the recommendations these three authors may have for the readers of their texts. In conclusion, these texts demonstrate that racialized identities are social constructs with measurable experiential effects. However, there are ways of actively resisting or even
- Full Text:
- Date Issued: 2016
- Authors: Mthembu, Lumumba
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/3322 , vital:20480
- Description: This study seeks to uncover the manner in which the young black experience is constructed in three novels by Sifiso Mzobe, Kgebetli Moele and K. Sello Duiker. Young Blood, Untitled and Thirteen Cents all feature teenage narrators navigating the social milieu of South Africa in the twenty-first century. My analysis is informed by Frantz Fanon’s postcolonial theory because South Africa’s socio-economic landscape conforms to the divisions laid out in The Wretched of the Earth. I contend that post-apartheid South Africa is developing in a manner that is symptomatic of the Fanonian post-independence African state. My close reading of the novels teases out the conditions under which young black subjects must survive and express themselves. I look into the roles of the community, the government, the family, and the school in shaping this experience. Naturally, my discussion segues into questions of sexuality and gender as they intersect with race. I demonstrate how these texts fail and succeed as works of Third Literature, a genre derived from Third Cinema, which I have adapted due to its Fanonian ideological underpinning. Third Literature is a fundamentally revolutionary and activistic genre which seeks to pave the way for social change. In this regard, I concern myself with the recommendations these three authors may have for the readers of their texts. In conclusion, these texts demonstrate that racialized identities are social constructs with measurable experiential effects. However, there are ways of actively resisting or even
- Full Text:
- Date Issued: 2016
A case study of democratic debate on People's Choice (PC) FM "Thahameso" and Harvest FM "Tsa Mabatooa" in Lesotho
- Falatsa, Mamolise Martha, Thipa, Henry
- Authors: Falatsa, Mamolise Martha , Thipa, Henry
- Date: 2016
- Subjects: Radio addresses, debates, etc. -- Lesotho , Radio broadcasting -- Lesotho , Mass media -- Political aspects -- Lesotho , Civil rights -- Lesotho
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/7281 , vital:21314
- Description: The study investigates the role of media in promoting free debate in Lesotho: A case study of democratic debate on People’s Choice (PC) FM “Thahameso” and Harvest FM “Tsa Mabatooa in Lesotho. Firstly, the study looked at the democratic communication in the volatile democracy of Lesotho, by providing historical factors of pre-independence and authoritarian governments, democrocatic governments prevailing and the dependence on South Africa. Secondly, the study provided literature on the role of broadcast media in different forms of government globally. Thirdly, it provides the analysis and transcription of one month’s recordings of the two political talk shows in Sesotho and identifies the communicative strategies used in this live on-air political discussion by talk show hosts, guests and callers. In these talk shows the researcher identifies the caller, host and guest behaviour and attitudes in discussions that relate the current political situation to the historical development of democracy in Lesotho alongside the economic and political influences from South Africa. The researcher also identifies that the talk show, guests and callers in the challenging political climate use traditional figurative expressions and biblical quotations to express their views. This leads the researcher to conclude that the political talk shows indeed facilitate participatory communication.
- Full Text:
- Date Issued: 2016
- Authors: Falatsa, Mamolise Martha , Thipa, Henry
- Date: 2016
- Subjects: Radio addresses, debates, etc. -- Lesotho , Radio broadcasting -- Lesotho , Mass media -- Political aspects -- Lesotho , Civil rights -- Lesotho
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/7281 , vital:21314
- Description: The study investigates the role of media in promoting free debate in Lesotho: A case study of democratic debate on People’s Choice (PC) FM “Thahameso” and Harvest FM “Tsa Mabatooa in Lesotho. Firstly, the study looked at the democratic communication in the volatile democracy of Lesotho, by providing historical factors of pre-independence and authoritarian governments, democrocatic governments prevailing and the dependence on South Africa. Secondly, the study provided literature on the role of broadcast media in different forms of government globally. Thirdly, it provides the analysis and transcription of one month’s recordings of the two political talk shows in Sesotho and identifies the communicative strategies used in this live on-air political discussion by talk show hosts, guests and callers. In these talk shows the researcher identifies the caller, host and guest behaviour and attitudes in discussions that relate the current political situation to the historical development of democracy in Lesotho alongside the economic and political influences from South Africa. The researcher also identifies that the talk show, guests and callers in the challenging political climate use traditional figurative expressions and biblical quotations to express their views. This leads the researcher to conclude that the political talk shows indeed facilitate participatory communication.
- Full Text:
- Date Issued: 2016
A case study of public service delivery in Cookhouse, Eastern Cape
- Makrwalana, Nomlindo Lillian
- Authors: Makrwalana, Nomlindo Lillian
- Date: 2016
- Subjects: Local government -- South Africa -- Eastern Cape , Municipal services -- South Africa -- Eastern Cape , Municipal services -- Management -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/6986 , vital:21188
- Description: In South Africa the economic gaps imposed by the previous apartheid government aggravated economic inequalities and caused considerable disparities, which has resulted in high unemployment rates. Inequalities were also manifest in the neglect of infrastructural and service provision as well in the effective absence of independent governance among some race groups. This led to a call for pro-active initiatives by the post-1994 democratic government to remedy the living condition of the previously disadvantage people. As part of this poverty relief drive the South African government has embarked on a series of developmental initiatives in bringing infrastructure related service to the poor and to reduce the enormous prevailing backlog, with the aim of increasing community participation, improving service delivery and promoting the upliftment of the lives of poor people through the medium of local governance. This study investigated the integrated Development Planning, which has been undertaken in Cookhouse in Blue Crane Route Municipality in the Eastern Cape to respond to the prevailing poverty and underdevelopment among the poor communities.
- Full Text:
- Date Issued: 2016
- Authors: Makrwalana, Nomlindo Lillian
- Date: 2016
- Subjects: Local government -- South Africa -- Eastern Cape , Municipal services -- South Africa -- Eastern Cape , Municipal services -- Management -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/6986 , vital:21188
- Description: In South Africa the economic gaps imposed by the previous apartheid government aggravated economic inequalities and caused considerable disparities, which has resulted in high unemployment rates. Inequalities were also manifest in the neglect of infrastructural and service provision as well in the effective absence of independent governance among some race groups. This led to a call for pro-active initiatives by the post-1994 democratic government to remedy the living condition of the previously disadvantage people. As part of this poverty relief drive the South African government has embarked on a series of developmental initiatives in bringing infrastructure related service to the poor and to reduce the enormous prevailing backlog, with the aim of increasing community participation, improving service delivery and promoting the upliftment of the lives of poor people through the medium of local governance. This study investigated the integrated Development Planning, which has been undertaken in Cookhouse in Blue Crane Route Municipality in the Eastern Cape to respond to the prevailing poverty and underdevelopment among the poor communities.
- Full Text:
- Date Issued: 2016
A change management model for the implementation of environmental sustainability principles at General Motors South Africa
- Authors: Mzuzu, Ncedisa
- Date: 2016
- Subjects: General Motors Corporation Organizational change -- Management , Corporate culture Business ethics
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/48047 , vital:40466
- Description: In this day and age, Environmental issues are considered to be very pertinent in a business environment. Lee (2010) argues that the natural environment is not only important for the general population, but the concern for the natural environment has become increasingly important within the accounting practice. Lee (2010) references (Porter & Van der Linde, 1995; Schaltegger & Wagner, 2006; Lee, 2009), in supporting his argument that there has been increasing interest in the relationship between environmental and economic performance, that is to say reducing costs while simultaneously improving environmental performance. Organisation in the past decades have either opted to disregard or embrace change as a result of this global phenomenon. Within organisations current leaders have had to manage operations in their local areas with a global mindset. Hill (2011:4) defines globalisation as a process whereby barriers to cross border trade and investment are declining, perceived trading distances are shrinking, material culture is starting to look similar and where national economies are merging to an interdependent, integrated economic system. With the increased hype and awareness of environmental and sustainability issues within the manufacturing environment, certain companies have adopted best practices that focus on firms' production processes (Hart, 1995; Stead & Stead, 1995) that can result in cost advantage. Within the South African context, the government has put in place a legislative framework laid down by the South African Constitution that enforces the responsibility of sustainable use of natural resources and responsible management of process outputs such as waste, effluent and gas emissions. General Motors adopted an Environmental Management System. The fundamental principles of EMS are based on continuous improvement where most of improvement opportunities and challenges exist within the implementation stages. The fundamental questions the study seeks to address are: As General Motors South Africa put in place this sustainability tool, how does the company ensure that in line with continuous improvement, the improvements are sustained? What interventions can the company implement to drive the change to ensure that it improves the implementation of its Environmental Management System so as to reap the benefits as outlined? This research effort discussed recommendations for achieving the objective of developing a change management model for improving implementation of sustainability principles at General Motors South Africa. Based on the outcome of the survey and the interview, the current senior managers at General Motors South Africa have embraced environmental issues, but there is no clear indication that the future leaders will also do the same. Based on the eight steps for transforming an organisation by Kotter (2006), the following are recommendations: A communication strategy to all employees (including leadership) that will continuously articulate connections between new behaviours and corporate success throughout the organisation, and not limit to manufacturing operations. Secondly, the company needs to ensure that there are programmes in place for leadership development and succession.
- Full Text:
- Date Issued: 2016
- Authors: Mzuzu, Ncedisa
- Date: 2016
- Subjects: General Motors Corporation Organizational change -- Management , Corporate culture Business ethics
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/48047 , vital:40466
- Description: In this day and age, Environmental issues are considered to be very pertinent in a business environment. Lee (2010) argues that the natural environment is not only important for the general population, but the concern for the natural environment has become increasingly important within the accounting practice. Lee (2010) references (Porter & Van der Linde, 1995; Schaltegger & Wagner, 2006; Lee, 2009), in supporting his argument that there has been increasing interest in the relationship between environmental and economic performance, that is to say reducing costs while simultaneously improving environmental performance. Organisation in the past decades have either opted to disregard or embrace change as a result of this global phenomenon. Within organisations current leaders have had to manage operations in their local areas with a global mindset. Hill (2011:4) defines globalisation as a process whereby barriers to cross border trade and investment are declining, perceived trading distances are shrinking, material culture is starting to look similar and where national economies are merging to an interdependent, integrated economic system. With the increased hype and awareness of environmental and sustainability issues within the manufacturing environment, certain companies have adopted best practices that focus on firms' production processes (Hart, 1995; Stead & Stead, 1995) that can result in cost advantage. Within the South African context, the government has put in place a legislative framework laid down by the South African Constitution that enforces the responsibility of sustainable use of natural resources and responsible management of process outputs such as waste, effluent and gas emissions. General Motors adopted an Environmental Management System. The fundamental principles of EMS are based on continuous improvement where most of improvement opportunities and challenges exist within the implementation stages. The fundamental questions the study seeks to address are: As General Motors South Africa put in place this sustainability tool, how does the company ensure that in line with continuous improvement, the improvements are sustained? What interventions can the company implement to drive the change to ensure that it improves the implementation of its Environmental Management System so as to reap the benefits as outlined? This research effort discussed recommendations for achieving the objective of developing a change management model for improving implementation of sustainability principles at General Motors South Africa. Based on the outcome of the survey and the interview, the current senior managers at General Motors South Africa have embraced environmental issues, but there is no clear indication that the future leaders will also do the same. Based on the eight steps for transforming an organisation by Kotter (2006), the following are recommendations: A communication strategy to all employees (including leadership) that will continuously articulate connections between new behaviours and corporate success throughout the organisation, and not limit to manufacturing operations. Secondly, the company needs to ensure that there are programmes in place for leadership development and succession.
- Full Text:
- Date Issued: 2016
A chiral hemiporphyrazine derivative
- Wu, Yanping, Gai, Lizhi, Xiao, Xuqiong, Lu, Hua, Li, Zhifang, Mack, John, Harris, Jessica, Nyokong, Tebello, Shen, Zhen
- Authors: Wu, Yanping , Gai, Lizhi , Xiao, Xuqiong , Lu, Hua , Li, Zhifang , Mack, John , Harris, Jessica , Nyokong, Tebello , Shen, Zhen
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/240404 , vital:50831 , xlink:href="https://doi.org/10.1002/asia.201600754"
- Description: The synthesis of an optically active hemiporphyrazine with chiral binaphthyl substituents (1) is reported, providing the first example of the incorporation of an intrinsically chiral moiety into the macrocyclic core of a hemiporphyrazine analogue. A negative circular dichroism (CD) signal is observed in the 325–450 nm region of the CD spectrum of (S,S)-1, while mainly positive bands are observed in the 220–325 nm region. Mirror symmetry is observed across the entire wavelength range of the CD spectra of (R,R)-1 and (S,S)-1. An irreversible one-electron oxidation wave with an onset potential at 1.07 V is observed by cyclic voltammetry, along with a reversible one-electron reduction wave at −0.85 V. Density functional calculations reproduce the experimentally observed data and trends, and provide further insight into the nature of the electronic transitions.
- Full Text:
- Date Issued: 2016
- Authors: Wu, Yanping , Gai, Lizhi , Xiao, Xuqiong , Lu, Hua , Li, Zhifang , Mack, John , Harris, Jessica , Nyokong, Tebello , Shen, Zhen
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/240404 , vital:50831 , xlink:href="https://doi.org/10.1002/asia.201600754"
- Description: The synthesis of an optically active hemiporphyrazine with chiral binaphthyl substituents (1) is reported, providing the first example of the incorporation of an intrinsically chiral moiety into the macrocyclic core of a hemiporphyrazine analogue. A negative circular dichroism (CD) signal is observed in the 325–450 nm region of the CD spectrum of (S,S)-1, while mainly positive bands are observed in the 220–325 nm region. Mirror symmetry is observed across the entire wavelength range of the CD spectra of (R,R)-1 and (S,S)-1. An irreversible one-electron oxidation wave with an onset potential at 1.07 V is observed by cyclic voltammetry, along with a reversible one-electron reduction wave at −0.85 V. Density functional calculations reproduce the experimentally observed data and trends, and provide further insight into the nature of the electronic transitions.
- Full Text:
- Date Issued: 2016
A combinatorial analysis of barred preferential arrangements
- Authors: Nkonkobe, Sithembele
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/36228 , vital:24530
- Description: For a non-negative integer n an ordered partition of a set Xn with n distinct elements is called a preferential arrangement (PA). A barred preferential arrangement (BPA) is a preferential arrangement with bars in between the blocks of the partition. An integer sequence an associated with the counting PA's of Xn has been intensely studied over a century and a half in many different contexts. In this thesis we develop a unified combinatorial framework to study the enumeration of BPAs and a special subclass of BPAs. The results of the study lead to a positive settlement of an open problem and a conjecture by Nelsen. We derive few important identities pertaining to the number of BPAs and restricted BPAs of an n element set using generating- functionology. Later we show that the number of restricted BPAs of Xn are intricately related to well-known numbers such as Eulerian numbers, Bell numbers, Poly-Bernoulli numbers and the number of equivalence classes of fuzzy subsets of Xn under some equivalent relation.
- Full Text:
- Date Issued: 2016
- Authors: Nkonkobe, Sithembele
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/36228 , vital:24530
- Description: For a non-negative integer n an ordered partition of a set Xn with n distinct elements is called a preferential arrangement (PA). A barred preferential arrangement (BPA) is a preferential arrangement with bars in between the blocks of the partition. An integer sequence an associated with the counting PA's of Xn has been intensely studied over a century and a half in many different contexts. In this thesis we develop a unified combinatorial framework to study the enumeration of BPAs and a special subclass of BPAs. The results of the study lead to a positive settlement of an open problem and a conjecture by Nelsen. We derive few important identities pertaining to the number of BPAs and restricted BPAs of an n element set using generating- functionology. Later we show that the number of restricted BPAs of Xn are intricately related to well-known numbers such as Eulerian numbers, Bell numbers, Poly-Bernoulli numbers and the number of equivalence classes of fuzzy subsets of Xn under some equivalent relation.
- Full Text:
- Date Issued: 2016
A comparative physicochemical study of unsymmetrical indium phthalocyanines in the presence of magnetic nanoparticles or quantum dots
- Osifeko, Olawale L, Nyokong, Tebello
- Authors: Osifeko, Olawale L , Nyokong, Tebello
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188743 , vital:44781 , xlink:href="https://doi.org/10.1080/00958972.2016.1152628"
- Description: Asymmetric indium phthalocyanine (3, containing an NH2 group) was conjugated (via an amide bond) to magnetic nanoparticle (MNP) functionalized with carboxylic acid or glutathione-capped CdTe/ZnSe/ZnO quantum dots to form 3-MNPs or 3-QDs. Techniques such as time-resolved fluorescence measurements, transmission electron microscopy, XPS, elemental analysis, FTIR, NMR (1H, 13C, and cozy), electronic spectroscopy, as well as mass spectroscopy were employed to characterize 3 and its nanoconjugates. The phthalocyanine conjugated to quantum dot (3-QDs) possesses the lowest Фpd higher Ф∆ and ФT as well as longer triplet lifetimes compares to 3-MNPs and free phthalocyanine.
- Full Text:
- Date Issued: 2016
- Authors: Osifeko, Olawale L , Nyokong, Tebello
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188743 , vital:44781 , xlink:href="https://doi.org/10.1080/00958972.2016.1152628"
- Description: Asymmetric indium phthalocyanine (3, containing an NH2 group) was conjugated (via an amide bond) to magnetic nanoparticle (MNP) functionalized with carboxylic acid or glutathione-capped CdTe/ZnSe/ZnO quantum dots to form 3-MNPs or 3-QDs. Techniques such as time-resolved fluorescence measurements, transmission electron microscopy, XPS, elemental analysis, FTIR, NMR (1H, 13C, and cozy), electronic spectroscopy, as well as mass spectroscopy were employed to characterize 3 and its nanoconjugates. The phthalocyanine conjugated to quantum dot (3-QDs) possesses the lowest Фpd higher Ф∆ and ФT as well as longer triplet lifetimes compares to 3-MNPs and free phthalocyanine.
- Full Text:
- Date Issued: 2016