HUMA: A platform for the analysis of genetic variation in humans
- Brown, David K, Tastan Bishop, Özlem
- Authors: Brown, David K , Tastan Bishop, Özlem
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124653 , vital:35642 , https://doi.10.1002/humu.23334
- Description: The completion of the human genome project at the beginning of the 21st century, along with the rapid advancement of sequencing technologies thereafter, has resulted in exponential growth of biological data. In genetics, this has given rise to numerous variation databases, created to store and annotate the ever-expanding dataset of known mutations. Usually, these databases focus on variation at the sequence level. Few databases focus on the analysis of variation at the 3D level, that is, mapping, visualizing, and determining the effects of variation in protein structures. Additionally, these Web servers seldom incorporate tools to help analyze these data. Here, we present the Human Mutation Analysis (HUMA) Web server and database. HUMA integrates sequence, structure, variation, and disease data into a single, connected database. A user-friendly interface provides click-based data access and visualization, whereas a RESTfulWebAPI provides programmatic access to the data. Tools have been integrated into HUMA to allow initial analyses to be carried out on the server. Furthermore, users can upload their private variation datasets, which are automatically mapped to public data and can be analyzed using the integrated tools. HUMA is freely accessible at https://huma.rubi.ru.ac.za.
- Full Text:
- Authors: Brown, David K , Tastan Bishop, Özlem
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124653 , vital:35642 , https://doi.10.1002/humu.23334
- Description: The completion of the human genome project at the beginning of the 21st century, along with the rapid advancement of sequencing technologies thereafter, has resulted in exponential growth of biological data. In genetics, this has given rise to numerous variation databases, created to store and annotate the ever-expanding dataset of known mutations. Usually, these databases focus on variation at the sequence level. Few databases focus on the analysis of variation at the 3D level, that is, mapping, visualizing, and determining the effects of variation in protein structures. Additionally, these Web servers seldom incorporate tools to help analyze these data. Here, we present the Human Mutation Analysis (HUMA) Web server and database. HUMA integrates sequence, structure, variation, and disease data into a single, connected database. A user-friendly interface provides click-based data access and visualization, whereas a RESTfulWebAPI provides programmatic access to the data. Tools have been integrated into HUMA to allow initial analyses to be carried out on the server. Furthermore, users can upload their private variation datasets, which are automatically mapped to public data and can be analyzed using the integrated tools. HUMA is freely accessible at https://huma.rubi.ru.ac.za.
- Full Text:
Human capital and other stories
- Authors: Dludlu, John
- Date: 2018
- Subjects: Short stories, South African (English) -- 21st century , South African fiction (English) -- 21st century
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/63121 , vital:28365
- Description: My collection of short stories is set mostly in Gauteng and revolves around mainly the lives of the urban, black elite almost three decades after the first non‐racial elections in South Africa. It captures emerging trends and fault lines and enquires into whether South Africa can continue on a different path from that of the rest of the continent. Themes covered in the collection, which still espouses idealism, include the acquisition of power, status and money, the use and abuse of these, as well as the psychosocial effects of money on this group. My writing is inspired by the courageous, inventive and introspective writings of the Drum generation of writers William Bloke Modisane, Nat Nakasa and Can Themba, as well as the use of language and the experimental form of writing as embodied in the work of Lidia Yuknavitch to deal with similarly pressing social issues of the day.
- Full Text:
- Authors: Dludlu, John
- Date: 2018
- Subjects: Short stories, South African (English) -- 21st century , South African fiction (English) -- 21st century
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/63121 , vital:28365
- Description: My collection of short stories is set mostly in Gauteng and revolves around mainly the lives of the urban, black elite almost three decades after the first non‐racial elections in South Africa. It captures emerging trends and fault lines and enquires into whether South Africa can continue on a different path from that of the rest of the continent. Themes covered in the collection, which still espouses idealism, include the acquisition of power, status and money, the use and abuse of these, as well as the psychosocial effects of money on this group. My writing is inspired by the courageous, inventive and introspective writings of the Drum generation of writers William Bloke Modisane, Nat Nakasa and Can Themba, as well as the use of language and the experimental form of writing as embodied in the work of Lidia Yuknavitch to deal with similarly pressing social issues of the day.
- Full Text:
Hybrid Sensor Simulation within an ICS Testbed
- Shaw, Brent, Irwin, Barry V W
- Authors: Shaw, Brent , Irwin, Barry V W
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427713 , vital:72457 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327624204_Hybrid_Sensor_Simulation_within_an_ICS_Testbed/links/5b9a50d8299bf14ad4d79587/Hybrid-Sensor-Simulation-within-an-ICS-Testbed.pdf
- Description: Industrial Control Systems (ICS) are responsible for managing factories, power-grids and water treatment facilities, and play a key role in running and controlling national Critical Information Infrastructure (CII). The integrity and availability of these systems are paramount, and the threat of cyberphysical attacks on these systems warrant thorough research into ensuring their security. The increasing interconnectivity seen in both the domestic and industrial sectors exposes numerous devices and systems to the Internet. These devices are exposed to malware and advanced persistent threats, that can affect CII through the attack of ICS. While simulations provide insights into how systems might react to certain changes, they generally lack the ability to be integrated into existing hardware systems. Hybrid testbeds could provide a platform for testing hardware and software components, enabling researchers to examine the interactions between various different networking through exploratory research and investigation in a controlled environment. This work presents an approach to traffic generation for use within ICS/IoT testbeds, through the production of Docker-based simulation nodes that are constructed based on the configuration of the system.
- Full Text:
- Authors: Shaw, Brent , Irwin, Barry V W
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427713 , vital:72457 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327624204_Hybrid_Sensor_Simulation_within_an_ICS_Testbed/links/5b9a50d8299bf14ad4d79587/Hybrid-Sensor-Simulation-within-an-ICS-Testbed.pdf
- Description: Industrial Control Systems (ICS) are responsible for managing factories, power-grids and water treatment facilities, and play a key role in running and controlling national Critical Information Infrastructure (CII). The integrity and availability of these systems are paramount, and the threat of cyberphysical attacks on these systems warrant thorough research into ensuring their security. The increasing interconnectivity seen in both the domestic and industrial sectors exposes numerous devices and systems to the Internet. These devices are exposed to malware and advanced persistent threats, that can affect CII through the attack of ICS. While simulations provide insights into how systems might react to certain changes, they generally lack the ability to be integrated into existing hardware systems. Hybrid testbeds could provide a platform for testing hardware and software components, enabling researchers to examine the interactions between various different networking through exploratory research and investigation in a controlled environment. This work presents an approach to traffic generation for use within ICS/IoT testbeds, through the production of Docker-based simulation nodes that are constructed based on the configuration of the system.
- Full Text:
I won’t be long
- Mhlambi, Ntombi Kayise Millicent
- Authors: Mhlambi, Ntombi Kayise Millicent
- Date: 2018
- Subjects: Creative writing (Higher education) -- South Africa , South African fiction (English) -- 21st century , South African poetry (English) -- 21st century , Short stories, South African (English) -- 21st century
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/63603 , vital:28446
- Description: My thesis is a weave of short stories, flash fiction and vignettes of prose-poetry. It uses lyrical, scenic and explorative modes to explore the stories of women, past, present and future, from all walks of life. These women, young and old, struggle to find their way within a ‘world’ characterised as Salithambo (the pink castle) whose structures and survival preys on their bodies. The stories explore the themes of girlhood and maturation, violence (specifically against women), animality, scatology, time, gender roles and expectations, and their rejection. I draw inspiration, stylistically, from Irenosen Okojie’s depiction of beauty and terror in the same sentence; Selah Saterstrom’s fragmented plot and directorial stroke; Taban Lo Liyong & Amos Tutuola’s avant-gardism and amplification of language; Adania Shibli’s sensorial and spare prose, Lyudmila Petrushevskaya, Lily Hoang & Carol Oates’ normalized magic spell, Athena Villaverde & Espido Freire’s imaginative overload of childhood; Shelley Jackson & Chevisa Woods’ construction of body parts as bearing texts or as texts themselves.
- Full Text:
- Authors: Mhlambi, Ntombi Kayise Millicent
- Date: 2018
- Subjects: Creative writing (Higher education) -- South Africa , South African fiction (English) -- 21st century , South African poetry (English) -- 21st century , Short stories, South African (English) -- 21st century
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/63603 , vital:28446
- Description: My thesis is a weave of short stories, flash fiction and vignettes of prose-poetry. It uses lyrical, scenic and explorative modes to explore the stories of women, past, present and future, from all walks of life. These women, young and old, struggle to find their way within a ‘world’ characterised as Salithambo (the pink castle) whose structures and survival preys on their bodies. The stories explore the themes of girlhood and maturation, violence (specifically against women), animality, scatology, time, gender roles and expectations, and their rejection. I draw inspiration, stylistically, from Irenosen Okojie’s depiction of beauty and terror in the same sentence; Selah Saterstrom’s fragmented plot and directorial stroke; Taban Lo Liyong & Amos Tutuola’s avant-gardism and amplification of language; Adania Shibli’s sensorial and spare prose, Lyudmila Petrushevskaya, Lily Hoang & Carol Oates’ normalized magic spell, Athena Villaverde & Espido Freire’s imaginative overload of childhood; Shelley Jackson & Chevisa Woods’ construction of body parts as bearing texts or as texts themselves.
- Full Text:
Igniting public space at the Chale Wote street art festival in Accra:
- Authors: Simbao, Ruth K
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147048 , vital:38588 , https://theconversation.com/igniting-public-space-at-the-chale-wote-street-art-festival-in-accra-102783
- Description: For the past eight years at the end of every August the James Town suburb of Ghana’s capital Accra has been taken over by the Chale Wote street art festival. During the festival, thousands of people, including local celebrities, artists, musicians, boxers and everyday revellers, move up and down the streets mostly by foot and at times on roller skates or unicycles.
- Full Text:
- Authors: Simbao, Ruth K
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147048 , vital:38588 , https://theconversation.com/igniting-public-space-at-the-chale-wote-street-art-festival-in-accra-102783
- Description: For the past eight years at the end of every August the James Town suburb of Ghana’s capital Accra has been taken over by the Chale Wote street art festival. During the festival, thousands of people, including local celebrities, artists, musicians, boxers and everyday revellers, move up and down the streets mostly by foot and at times on roller skates or unicycles.
- Full Text:
Impact of invasive alien plants on water provision in selected catchments
- Preston, Ian R, Le Maitre, D C, Blignaut, J N, Louw, Lynette, Palmer, Carolyn G
- Authors: Preston, Ian R , Le Maitre, D C , Blignaut, J N , Louw, Lynette , Palmer, Carolyn G
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/437979 , vital:73426 , ISBN 1816-7950 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/44_04_20_33741.pdf
- Description: We analyse the impact of failing to control invasive alien plants (IAPs) on the water supply to the Berg River and De Hoop Dams, in other words, the opportunity cost of not clearing IAPs in these two catch-ments. To do this we used models to assess and compare the impact of current and future invasions on inflows into the dams. Although the clearing of current invasions would only provide a modest increase in the amount of water compared to, for example, the construction of an-other dam, failure to clear the invasion will have a negative impact on water security in the long term. We estimated that the Berg River Dam could lose up to 51% of its mean annual inflows to IAPs over a 45-year period, and the De Hoop Dam catchment could lose up to 44%. These impacts would continue to increase over time, and the costs of control could become very high as the plants invade rugged terrain. Major in-frastructural development requires Ministerial approval, supported by advice from senior officials. We suggest that such advice should sub-stantively take sufficient account of the benefits of clearing existing in-vasions, or at least of preventing further invasions. Our results suggest that serious consequences arise from insufficient investment in catch-ment management. An integrated approach to the management of the supply of and demand for water, that ensures long-term sustainability, is essential in informed decision-making and the early control of IAPs is a key component of that approach.
- Full Text:
- Authors: Preston, Ian R , Le Maitre, D C , Blignaut, J N , Louw, Lynette , Palmer, Carolyn G
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/437979 , vital:73426 , ISBN 1816-7950 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/44_04_20_33741.pdf
- Description: We analyse the impact of failing to control invasive alien plants (IAPs) on the water supply to the Berg River and De Hoop Dams, in other words, the opportunity cost of not clearing IAPs in these two catch-ments. To do this we used models to assess and compare the impact of current and future invasions on inflows into the dams. Although the clearing of current invasions would only provide a modest increase in the amount of water compared to, for example, the construction of an-other dam, failure to clear the invasion will have a negative impact on water security in the long term. We estimated that the Berg River Dam could lose up to 51% of its mean annual inflows to IAPs over a 45-year period, and the De Hoop Dam catchment could lose up to 44%. These impacts would continue to increase over time, and the costs of control could become very high as the plants invade rugged terrain. Major in-frastructural development requires Ministerial approval, supported by advice from senior officials. We suggest that such advice should sub-stantively take sufficient account of the benefits of clearing existing in-vasions, or at least of preventing further invasions. Our results suggest that serious consequences arise from insufficient investment in catch-ment management. An integrated approach to the management of the supply of and demand for water, that ensures long-term sustainability, is essential in informed decision-making and the early control of IAPs is a key component of that approach.
- Full Text:
Improved Photophysical and Photochemical Properties of Thiopheneethoxy Substituted Metallophthalocyanines on Immobilization onto Gold‐speckled Silica Nanoparticles
- Dube, Edith, Oluwole, David O, Nyokong, Tebello
- Authors: Dube, Edith , Oluwole, David O , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187699 , vital:44688 , xlink:href="https://doi.org/10.1111/php.12879"
- Description: This work reports on the synthesis of tetrakis-[(thiophineethoxy) phthalocyaninato] indium(II) chloride (3). The photophysical behavior of complex 3 was compared to that of the Zn derivative (tetrakis-[(thiophineethoxy) phthalocyaninato] zinc(II) (complex 2)). The compounds were interacted with gold-speckled silica (GSS) nanoparticles via Au–S self assembly to afford the conjugates (2–GSS and 3–GSS). The photophysicochemical behavior of the compounds and their conjugates were assessed. The conjugates afforded a decrease in fluorescence quantum yields and lifetimes with improved triplet and singlet oxygen quantum yields in comparison with complexes 2 and 3 alone. The complexes and their conjugates could serve as good candidates for photodynamic therapy.
- Full Text:
- Authors: Dube, Edith , Oluwole, David O , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187699 , vital:44688 , xlink:href="https://doi.org/10.1111/php.12879"
- Description: This work reports on the synthesis of tetrakis-[(thiophineethoxy) phthalocyaninato] indium(II) chloride (3). The photophysical behavior of complex 3 was compared to that of the Zn derivative (tetrakis-[(thiophineethoxy) phthalocyaninato] zinc(II) (complex 2)). The compounds were interacted with gold-speckled silica (GSS) nanoparticles via Au–S self assembly to afford the conjugates (2–GSS and 3–GSS). The photophysicochemical behavior of the compounds and their conjugates were assessed. The conjugates afforded a decrease in fluorescence quantum yields and lifetimes with improved triplet and singlet oxygen quantum yields in comparison with complexes 2 and 3 alone. The complexes and their conjugates could serve as good candidates for photodynamic therapy.
- Full Text:
In silico characterization of plasmodial transketolases as potential malaria drug target
- Authors: Boateng, Rita Afriyie
- Date: 2018
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/63540 , vital:28433
- Description: Expected release date-April 2019
- Full Text:
- Authors: Boateng, Rita Afriyie
- Date: 2018
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/63540 , vital:28433
- Description: Expected release date-April 2019
- Full Text:
In silico study of Plasmodium 1-deoxy-dxylulose 5-phosphate reductoisomerase (DXR) for identification of novel inhibitors from SANCDB
- Authors: Diallo, Bakary N'tji
- Date: 2018
- Subjects: Plasmodium 1-deoxy-dxylulose 5-phosphate reductoisomerase , Isoprenoids , Plasmodium , Antimalarials , Malaria -- Chemotherapy , Molecules -- Models , Molecular dynamics , South African Natural Compounds Database
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/64012 , vital:28523
- Description: Malaria remains a major health concern with a complex parasite constantly developing resistance to the different drugs introduced to treat it, threatening the efficacy of the current ACT treatment recommended by WHO (World Health Organization). Different antimalarial compounds with different mechanisms of action are ideal as this decreases chances of resistance occurring. Inhibiting DXR and consequently the MEP pathway is a good strategy to find a new antimalarial with a novel mode of action. From literature, all the enzymes of the MEP pathway have also been shown to be indispensable for the synthesis of isoprenoids. They have been validated as drug targets and the X-ray structure of each of the enzymes has been solved. DXR is a protein which catalyses the second step of the MEP pathway. There are currently 255 DXR inhibitors in the Binding Database (accessed November 2017) generally based on the fosmidomycin structural scaffold and thus often showing poor drug likeness properties. This study aims to research new DXR inhibitors using in silico techniques. We analysed the protein sequence and built 3D models in close and open conformations for the different Plasmodium sequences. Then SANCDB compounds were screened to identify new potential DXR inhibitors with new chemical scaffolds. Finally, the identified hits were submitted to molecular dynamics studies, preceded by a parameterization of the manganese atom in the protein active site.
- Full Text:
- Authors: Diallo, Bakary N'tji
- Date: 2018
- Subjects: Plasmodium 1-deoxy-dxylulose 5-phosphate reductoisomerase , Isoprenoids , Plasmodium , Antimalarials , Malaria -- Chemotherapy , Molecules -- Models , Molecular dynamics , South African Natural Compounds Database
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/64012 , vital:28523
- Description: Malaria remains a major health concern with a complex parasite constantly developing resistance to the different drugs introduced to treat it, threatening the efficacy of the current ACT treatment recommended by WHO (World Health Organization). Different antimalarial compounds with different mechanisms of action are ideal as this decreases chances of resistance occurring. Inhibiting DXR and consequently the MEP pathway is a good strategy to find a new antimalarial with a novel mode of action. From literature, all the enzymes of the MEP pathway have also been shown to be indispensable for the synthesis of isoprenoids. They have been validated as drug targets and the X-ray structure of each of the enzymes has been solved. DXR is a protein which catalyses the second step of the MEP pathway. There are currently 255 DXR inhibitors in the Binding Database (accessed November 2017) generally based on the fosmidomycin structural scaffold and thus often showing poor drug likeness properties. This study aims to research new DXR inhibitors using in silico techniques. We analysed the protein sequence and built 3D models in close and open conformations for the different Plasmodium sequences. Then SANCDB compounds were screened to identify new potential DXR inhibitors with new chemical scaffolds. Finally, the identified hits were submitted to molecular dynamics studies, preceded by a parameterization of the manganese atom in the protein active site.
- Full Text:
In vitro analysis of putative cancer stem cell populations and chemosensitivity in the SW480 and SW620 colon cancer metastasis model:
- Slater, Cindy, de la Mare, Jo-Anne, Edkins, Adrienne L
- Authors: Slater, Cindy , de la Mare, Jo-Anne , Edkins, Adrienne L
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/164401 , vital:41115 , DOI: 10.3892/ol.2018.8431
- Description: The cancer stem cell (CSC) theory implicates a small subpopulation of cells with stem like properties, which is responsible for tumour initiation, development and metastasis. The unique biological and functional characteristics of CSCs, widely associated with treatment resistance, indicate an association between metastasis and stemness. It was hypothesised that metastatic cell lines may be enriched in CSCs and that this would correlate with a more resistant tumour. In the present study, the SW480 and SW620 paired cell lines derived from a colon adenocarcinoma and its lymph node metastasis, respectively were compared as an in vitro model of cancer progression. Their chemosensitivity and CSC properties were investigated. A range of in vitro assays were performed, including the side population assay, ALDEFLUOR assay, tumoursphere assay and assessment of CSC associated surface phenotypes.
- Full Text:
- Authors: Slater, Cindy , de la Mare, Jo-Anne , Edkins, Adrienne L
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/164401 , vital:41115 , DOI: 10.3892/ol.2018.8431
- Description: The cancer stem cell (CSC) theory implicates a small subpopulation of cells with stem like properties, which is responsible for tumour initiation, development and metastasis. The unique biological and functional characteristics of CSCs, widely associated with treatment resistance, indicate an association between metastasis and stemness. It was hypothesised that metastatic cell lines may be enriched in CSCs and that this would correlate with a more resistant tumour. In the present study, the SW480 and SW620 paired cell lines derived from a colon adenocarcinoma and its lymph node metastasis, respectively were compared as an in vitro model of cancer progression. Their chemosensitivity and CSC properties were investigated. A range of in vitro assays were performed, including the side population assay, ALDEFLUOR assay, tumoursphere assay and assessment of CSC associated surface phenotypes.
- Full Text:
In vitro antimalarial, antitrypanosomal and HIV-1 integrase inhibitory activities of two Cameroonian medicinal plants: Antrocaryon klaineanum (Anacardiaceae) and Diospyros conocarpa (Ebenaceae)
- Fouokeng, Y, Feusso, H M Feumo, Noundou, Xavier S, Krause, Rui W M, Teinkela, Jean E Mb, Wintjens, R, Hoppe, Heinrich C, Azebaze, Anatole G B, Vardamides, Juliette C, Isaacs, Michelle
- Authors: Fouokeng, Y , Feusso, H M Feumo , Noundou, Xavier S , Krause, Rui W M , Teinkela, Jean E Mb , Wintjens, R , Hoppe, Heinrich C , Azebaze, Anatole G B , Vardamides, Juliette C , Isaacs, Michelle
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/126653 , vital:35908 , https://doi.org/10.1016/j.sajb.2018.10.008
- Description: Antiplasmodial, antitrypanosomal and anti-HIV-1 activities of crude extracts, fractions and some isolated compounds from two Cameroonian medicinal plants: Antrocaryon klaineanum Pierre (Anacardiaceae) and Diospyros conocarpa Gürke ex K. Schum. (Ebenaceae) were assessed. The phytochemical studies led to the isolation of eight compounds (1–8) from Diospyros conocarpa and six compounds (6, 9–13) from Antrocaryon klaineanum. These compounds were identified as mangiferolic acid (1), 3β, 22(S)-dihydroxycycloart-24E-en-26-oic acid (2), lupeol (3), aridanin (4), betulin (5), betulinic acid (6), bergenin (7), D-quercitol(8), entilin C(9), entilin A(10), antrocarine A(11), 7R,20(S)-dihydroxy-4,24(28)-ergostadien-3-one(12) and stigmasterol glucoside (13). The criteria for activity were set as follows: an IC50 value
- Full Text:
- Authors: Fouokeng, Y , Feusso, H M Feumo , Noundou, Xavier S , Krause, Rui W M , Teinkela, Jean E Mb , Wintjens, R , Hoppe, Heinrich C , Azebaze, Anatole G B , Vardamides, Juliette C , Isaacs, Michelle
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/126653 , vital:35908 , https://doi.org/10.1016/j.sajb.2018.10.008
- Description: Antiplasmodial, antitrypanosomal and anti-HIV-1 activities of crude extracts, fractions and some isolated compounds from two Cameroonian medicinal plants: Antrocaryon klaineanum Pierre (Anacardiaceae) and Diospyros conocarpa Gürke ex K. Schum. (Ebenaceae) were assessed. The phytochemical studies led to the isolation of eight compounds (1–8) from Diospyros conocarpa and six compounds (6, 9–13) from Antrocaryon klaineanum. These compounds were identified as mangiferolic acid (1), 3β, 22(S)-dihydroxycycloart-24E-en-26-oic acid (2), lupeol (3), aridanin (4), betulin (5), betulinic acid (6), bergenin (7), D-quercitol(8), entilin C(9), entilin A(10), antrocarine A(11), 7R,20(S)-dihydroxy-4,24(28)-ergostadien-3-one(12) and stigmasterol glucoside (13). The criteria for activity were set as follows: an IC50 value
- Full Text:
In-situ synthesis of gold nanoparticles on graphene quantum dots-phthalocyanine nanoplatforms: First description of the photophysical and surface enhanced Raman scattering behaviour
- Nwahara, Nnamdi, Achadu, Ojodomo John, Nyokong, Tebello
- Authors: Nwahara, Nnamdi , Achadu, Ojodomo John , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187638 , vital:44682 , xlink:href="https://doi.org/10.1016/j.jphotochem.2018.04.011"
- Description: Owing to the need for new low-dimensional molecular assemblies with tailored electronic properties, the current study presents a facile approach for the synthesis and assembly of gold nanoparticles (AuNPs) onto functional graphene quantum dots (GQDs)-phthalocyanines (Pcs) arrays and the investigation of their photophysical and surface enhanced Raman scattering (SERS) properties. The GQDs were functionalized with L-glutathione (GSH) (to form GQDs@GSH) in order to assist coupling to the low symmetry Zn tris–(tert–butyl) mono carboxyphenoxy (propionic acid) phthalocyanine (complex 1) to form 1@GQDs. The affinity of gold (Au) to sulphur (S) was exploited for the assembly of the AuNPs onto 1@GQDs platform to form 1@GQDs-AuNPs. Transmission electron microscopic investigations confirmed the formation of monodispersed, spherical Pc/GQDs@GSH/AuNPs hybrids. The nanocomposite displayed high triplet quantum yields, which translated into high singlet oxygen quantum yield as high as 87%. Furthermore, the formed composites demonstrated strong surface enhanced Raman scattering (SERS) properties with an unprecedented intrinsic maximal enhancement factor of more than 30-fold. These nanostructures also retain more than 90% of their original SERS intensities after a week of storage, displaying superb stability under ambient conditions. These results highlight the remarkable potential of this composite as a unique Raman-based PDT dosimetric agent.
- Full Text:
- Authors: Nwahara, Nnamdi , Achadu, Ojodomo John , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187638 , vital:44682 , xlink:href="https://doi.org/10.1016/j.jphotochem.2018.04.011"
- Description: Owing to the need for new low-dimensional molecular assemblies with tailored electronic properties, the current study presents a facile approach for the synthesis and assembly of gold nanoparticles (AuNPs) onto functional graphene quantum dots (GQDs)-phthalocyanines (Pcs) arrays and the investigation of their photophysical and surface enhanced Raman scattering (SERS) properties. The GQDs were functionalized with L-glutathione (GSH) (to form GQDs@GSH) in order to assist coupling to the low symmetry Zn tris–(tert–butyl) mono carboxyphenoxy (propionic acid) phthalocyanine (complex 1) to form 1@GQDs. The affinity of gold (Au) to sulphur (S) was exploited for the assembly of the AuNPs onto 1@GQDs platform to form 1@GQDs-AuNPs. Transmission electron microscopic investigations confirmed the formation of monodispersed, spherical Pc/GQDs@GSH/AuNPs hybrids. The nanocomposite displayed high triplet quantum yields, which translated into high singlet oxygen quantum yield as high as 87%. Furthermore, the formed composites demonstrated strong surface enhanced Raman scattering (SERS) properties with an unprecedented intrinsic maximal enhancement factor of more than 30-fold. These nanostructures also retain more than 90% of their original SERS intensities after a week of storage, displaying superb stability under ambient conditions. These results highlight the remarkable potential of this composite as a unique Raman-based PDT dosimetric agent.
- Full Text:
In-situ synthesis of gold nanoparticles on graphene quantum dots-phthalocyanine nanoplatforms: First description of the photophysical and surface enhanced Raman scattering behaviour
- Nwahara, Nnamdi, Achadu, Ojodomo John, Nyokong, Tebello
- Authors: Nwahara, Nnamdi , Achadu, Ojodomo John , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188183 , vital:44730 , xlink:href="https://doi.org/10.1016/j.jphotochem.2018.04.011"
- Description: Owing to the need for new low-dimensional molecular assemblies with tailored electronic properties, the current study presents a facile approach for the synthesis and assembly of gold nanoparticles (AuNPs) onto functional graphene quantum dots (GQDs)-phthalocyanines (Pcs) arrays and the investigation of their photophysical and surface enhanced Raman scattering (SERS) properties. The GQDs were functionalized with L-glutathione (GSH) (to form GQDs@GSH) in order to assist coupling to the low symmetry Zn tris–(tert–butyl) mono carboxyphenoxy (propionic acid) phthalocyanine (complex 1) to form 1@GQDs. The affinity of gold (Au) to sulphur (S) was exploited for the assembly of the AuNPs onto 1@GQDs platform to form 1@GQDs-AuNPs. Transmission electron microscopic investigations confirmed the formation of monodispersed, spherical Pc/GQDs@GSH/AuNPs hybrids. The nanocomposite displayed high triplet quantum yields, which translated into high singlet oxygen quantum yield as high as 87%. Furthermore, the formed composites demonstrated strong surface enhanced Raman scattering (SERS) properties with an unprecedented intrinsic maximal enhancement factor of more than 30-fold. These nanostructures also retain more than 90% of their original SERS intensities after a week of storage, displaying superb stability under ambient conditions. These results highlight the remarkable potential of this composite as a unique Raman-based PDT dosimetric agent.
- Full Text:
- Authors: Nwahara, Nnamdi , Achadu, Ojodomo John , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188183 , vital:44730 , xlink:href="https://doi.org/10.1016/j.jphotochem.2018.04.011"
- Description: Owing to the need for new low-dimensional molecular assemblies with tailored electronic properties, the current study presents a facile approach for the synthesis and assembly of gold nanoparticles (AuNPs) onto functional graphene quantum dots (GQDs)-phthalocyanines (Pcs) arrays and the investigation of their photophysical and surface enhanced Raman scattering (SERS) properties. The GQDs were functionalized with L-glutathione (GSH) (to form GQDs@GSH) in order to assist coupling to the low symmetry Zn tris–(tert–butyl) mono carboxyphenoxy (propionic acid) phthalocyanine (complex 1) to form 1@GQDs. The affinity of gold (Au) to sulphur (S) was exploited for the assembly of the AuNPs onto 1@GQDs platform to form 1@GQDs-AuNPs. Transmission electron microscopic investigations confirmed the formation of monodispersed, spherical Pc/GQDs@GSH/AuNPs hybrids. The nanocomposite displayed high triplet quantum yields, which translated into high singlet oxygen quantum yield as high as 87%. Furthermore, the formed composites demonstrated strong surface enhanced Raman scattering (SERS) properties with an unprecedented intrinsic maximal enhancement factor of more than 30-fold. These nanostructures also retain more than 90% of their original SERS intensities after a week of storage, displaying superb stability under ambient conditions. These results highlight the remarkable potential of this composite as a unique Raman-based PDT dosimetric agent.
- Full Text:
Incorporation of metal free and Ga 5, 10, 15, 20-tetrakis (4-bromophenyl) porphyrin into Pluronic F127-folic acid micelles
- Managa, Muthumuni, Ngoy, Bucolome P, Mafukidze, Donovan M, Nyokong, Tebello
- Authors: Managa, Muthumuni , Ngoy, Bucolome P , Mafukidze, Donovan M , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/233256 , vital:50073 , xlink:href="https://doi.org/10.1016/j.jlumin.2017.09.045"
- Description: ClGa 5,10,15,20-Tetrakis (4-bromophenyl) porphyrinato (ClGaTBrPP) and its metal free derivative were successfully synthesized and incorporated into Pluronic F127 polymeric micelles that has been conjugated to folic acid (FA) to form ClGaTBrPP-F127-FA (or H2TBrPP-F127-FA). For comparison, ClGaTBrPP-F127 and H2TBrPP-F127 (without FA) were also formed. The singlet oxygen quantum yield for ClGaTBrPP-F127-FA was higher (ΦΔ = 0.44) than that of H2TBrPP-F127-FA (ΦΔ = 0.37), due to the heavy atom effect of Ga in the former which encourages intersystem crossing to the triplet state. The same applies to ClGaTBrPP-F127 (ΦΔ = 0.47) and H2TBrPP-F127 (ΦΔ = 0.41). Thus, ΦΔ values decreased in the presence of FA, but still high enough for practical application of the nanodrug system. The binding constants Kb were determined to be 1.08 × 104 M−1, 2.51 × 105 M−1, 1.52 × 103 and 2.68 × 103 for H2TBrPP+F127-FA, ClGaTBrPP+F127-FA, ClGaTBrPP-F127 and H2TBrPP-F127, respectively. The Kp values were determined in biphasic octanol and water system.
- Full Text:
- Authors: Managa, Muthumuni , Ngoy, Bucolome P , Mafukidze, Donovan M , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/233256 , vital:50073 , xlink:href="https://doi.org/10.1016/j.jlumin.2017.09.045"
- Description: ClGa 5,10,15,20-Tetrakis (4-bromophenyl) porphyrinato (ClGaTBrPP) and its metal free derivative were successfully synthesized and incorporated into Pluronic F127 polymeric micelles that has been conjugated to folic acid (FA) to form ClGaTBrPP-F127-FA (or H2TBrPP-F127-FA). For comparison, ClGaTBrPP-F127 and H2TBrPP-F127 (without FA) were also formed. The singlet oxygen quantum yield for ClGaTBrPP-F127-FA was higher (ΦΔ = 0.44) than that of H2TBrPP-F127-FA (ΦΔ = 0.37), due to the heavy atom effect of Ga in the former which encourages intersystem crossing to the triplet state. The same applies to ClGaTBrPP-F127 (ΦΔ = 0.47) and H2TBrPP-F127 (ΦΔ = 0.41). Thus, ΦΔ values decreased in the presence of FA, but still high enough for practical application of the nanodrug system. The binding constants Kb were determined to be 1.08 × 104 M−1, 2.51 × 105 M−1, 1.52 × 103 and 2.68 × 103 for H2TBrPP+F127-FA, ClGaTBrPP+F127-FA, ClGaTBrPP-F127 and H2TBrPP-F127, respectively. The Kp values were determined in biphasic octanol and water system.
- Full Text:
Influence of annealing on thermoluminescence of natural quartz: kinetic analysis and experimental study of apparent inverse thermal quenching
- Folley, Damilola E, Chithambo, Makaiko L
- Authors: Folley, Damilola E , Chithambo, Makaiko L
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/109996 , vital:33212 , https://doi.org/10.1016/j.radmeas.2018.04.010
- Description: The influence of annealing on the main thermoluminescence glow-peak of natural quartz is reported. For comparison, results from un-annealed quartz are included. The glow-curve measured at 1 °Cs−1 after beta irradiation to 50 Gy revealed six peaks each for quartz annealed at 800 °C for 1 h and the un-annealed sample. The main peak in both quartzes was observed at 72 °C. This report focusses on kinetic analysis of the main peak. The analysis was carried out using various methods consisting of the initial rise, whole glow-peak, peak shape, variable heating rate and phosphorescence-based methods. The activation energy obtained using the various methods ranges between and for the annealed sample and between and for the un-annealed sample. The result suggests that annealing has little effect on the activation energy. The luminescence intensity decreased with heating rate in the un-annealed sample in a manner suggestive of thermal quenching. In contrast, the dependence of intensity on heating rate in the annealed sample is influenced by the dose the sample is irradiated to. Whereas thermal quenching was noted for a dose of 50 Gy in the un-annealed sample, the annealed sample showed evidence of thermal quenching at a low dose of 3 Gy with the opposite effect when irradiated to 50 Gy. The activation energies of thermal quenching were found as and for the un-annealed and annealed samples respectively. We ascribe the apparent dependence of thermal quenching on dose in the annealed sample to competition between radiative and non-radiative transitions at the recombination centre.
- Full Text: false
- Authors: Folley, Damilola E , Chithambo, Makaiko L
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/109996 , vital:33212 , https://doi.org/10.1016/j.radmeas.2018.04.010
- Description: The influence of annealing on the main thermoluminescence glow-peak of natural quartz is reported. For comparison, results from un-annealed quartz are included. The glow-curve measured at 1 °Cs−1 after beta irradiation to 50 Gy revealed six peaks each for quartz annealed at 800 °C for 1 h and the un-annealed sample. The main peak in both quartzes was observed at 72 °C. This report focusses on kinetic analysis of the main peak. The analysis was carried out using various methods consisting of the initial rise, whole glow-peak, peak shape, variable heating rate and phosphorescence-based methods. The activation energy obtained using the various methods ranges between and for the annealed sample and between and for the un-annealed sample. The result suggests that annealing has little effect on the activation energy. The luminescence intensity decreased with heating rate in the un-annealed sample in a manner suggestive of thermal quenching. In contrast, the dependence of intensity on heating rate in the annealed sample is influenced by the dose the sample is irradiated to. Whereas thermal quenching was noted for a dose of 50 Gy in the un-annealed sample, the annealed sample showed evidence of thermal quenching at a low dose of 3 Gy with the opposite effect when irradiated to 50 Gy. The activation energies of thermal quenching were found as and for the un-annealed and annealed samples respectively. We ascribe the apparent dependence of thermal quenching on dose in the annealed sample to competition between radiative and non-radiative transitions at the recombination centre.
- Full Text: false
Influence of knowledge of the end-point on pacing during a 2000m rowing time trial
- Authors: Ferreira, Dean
- Date: 2018
- Subjects: Rowing -- Training , Rowing -- Coaching , Endurance sports -- Training , Rowers -- Ability testing , Rowing -- Training -- Psychological aspects
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/61636 , vital:28044
- Description: Introduction: A typical 2000 m rowing race requires maximal force production over six to eight minutes. Optimal distribution of energetic resources during such a race is vital for optimal performance. There is little research examining the pacing strategies employed by rowers, particularly at the sub-elite level. Aim: The purpose of this investigation was to determine the influence of knowledge of the end-point on pacing during a 2000 m rowing time trial. Methods: Eleven male rowers from a university rowing club volunteered to partake in the study. Each participant completed three experimental trials on an indoor rowing ergometer, each 2000 m. The only difference between the trials was the nature of the information provided beforehand. At the start of the control trial, participants were correctly informed about the distance to be covered. Participants were not informed of the distance to be completed in the unknown trial. For the deceptive trial, participants were told 1000 m would be completed, but when this distance was reached, they were told to continue for another 1000 m. During each trial muscle activity, power output, heart rate, performance time and perceptions of effort were measured.Results: The control trial was significantly (p<0.05) faster than both the unknown and deceptive trials, however the deceptive trial was the fastest of all trials at the 1000 m distance. The unknown trial was slowest at 1000 m and at 2000 m. Muscle activity, RPE, heart rate and power output were significantly (p<0.05) lower in the unknown trial compared to the control and deceptive trial. The control trial exhibited a reverse J-shape pacing profile. The deceptive trial revealed a significant (p<0.05) reduction in performance time, heart rate, power output and muscle activity after the 1000 m interval. The first 500 m interval had the fastest performance and highest power output in all trials. In all trials, RPE was highest at the end of the 2000 m, the greatest reading being obtained at the end of the control trial. During the first 1000 m of the deceptive trial, the dependant variables were similar to those in the control trial. Once the deception was revealed, there was a significant (p<0.05) reduction in the muscle activity, heart rate and power output. Conclusion: The results of this study indicate that accurate end-point information is crucial to the development of an optimal pacing strategy, and ultimately to successful performance. Rowers tend to adopt the reverse J-shape pacing profile most often due to the tactical and physiological benefits offered by this strategy. Unknown or inaccurate end-point information resulted in performance decrements due to the uncertainty associated with the exercise bout.
- Full Text:
- Authors: Ferreira, Dean
- Date: 2018
- Subjects: Rowing -- Training , Rowing -- Coaching , Endurance sports -- Training , Rowers -- Ability testing , Rowing -- Training -- Psychological aspects
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/61636 , vital:28044
- Description: Introduction: A typical 2000 m rowing race requires maximal force production over six to eight minutes. Optimal distribution of energetic resources during such a race is vital for optimal performance. There is little research examining the pacing strategies employed by rowers, particularly at the sub-elite level. Aim: The purpose of this investigation was to determine the influence of knowledge of the end-point on pacing during a 2000 m rowing time trial. Methods: Eleven male rowers from a university rowing club volunteered to partake in the study. Each participant completed three experimental trials on an indoor rowing ergometer, each 2000 m. The only difference between the trials was the nature of the information provided beforehand. At the start of the control trial, participants were correctly informed about the distance to be covered. Participants were not informed of the distance to be completed in the unknown trial. For the deceptive trial, participants were told 1000 m would be completed, but when this distance was reached, they were told to continue for another 1000 m. During each trial muscle activity, power output, heart rate, performance time and perceptions of effort were measured.Results: The control trial was significantly (p<0.05) faster than both the unknown and deceptive trials, however the deceptive trial was the fastest of all trials at the 1000 m distance. The unknown trial was slowest at 1000 m and at 2000 m. Muscle activity, RPE, heart rate and power output were significantly (p<0.05) lower in the unknown trial compared to the control and deceptive trial. The control trial exhibited a reverse J-shape pacing profile. The deceptive trial revealed a significant (p<0.05) reduction in performance time, heart rate, power output and muscle activity after the 1000 m interval. The first 500 m interval had the fastest performance and highest power output in all trials. In all trials, RPE was highest at the end of the 2000 m, the greatest reading being obtained at the end of the control trial. During the first 1000 m of the deceptive trial, the dependant variables were similar to those in the control trial. Once the deception was revealed, there was a significant (p<0.05) reduction in the muscle activity, heart rate and power output. Conclusion: The results of this study indicate that accurate end-point information is crucial to the development of an optimal pacing strategy, and ultimately to successful performance. Rowers tend to adopt the reverse J-shape pacing profile most often due to the tactical and physiological benefits offered by this strategy. Unknown or inaccurate end-point information resulted in performance decrements due to the uncertainty associated with the exercise bout.
- Full Text:
Influence of land cover, proximity to streams and household topographical location on flooding impact in informal settlements in the Eastern Cape, South Africa
- Dalu, Mwazvita, Shackleton, Charlie M, Dalu, Tatenda
- Authors: Dalu, Mwazvita , Shackleton, Charlie M , Dalu, Tatenda
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182089 , vital:43799 , xlink:href="https://doi.org/10.1016/j.ijdrr.2017.12.009"
- Description: Patterns of land use, household topographical location and state of natural vegetation influence the spatial distribution of flooding impact. Using field observations and GIS mapping techniques, we investigated how landscape factors influenced structural flooding impact in informal settlements. This study was carried out in the informal settlements of the Eastern Cape Province of South Africa, after the October 2012 floods. Increasing slope significantly raised the probability and level of damage by at least 30% in five of the seven sites, whereas proximity to river and wetlands (more than 100 m) was significant in only two of the sites and at lower levels. Multi-regression analysis highlighted that land cover, proximity to streams and household topographical location influenced the impact of flooding on housing structures. We found that the impact on housing structures in informal settlements during the floods were significantly influenced by their proximity to water bodies, slope factor and patterns of land cover.
- Full Text:
- Authors: Dalu, Mwazvita , Shackleton, Charlie M , Dalu, Tatenda
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182089 , vital:43799 , xlink:href="https://doi.org/10.1016/j.ijdrr.2017.12.009"
- Description: Patterns of land use, household topographical location and state of natural vegetation influence the spatial distribution of flooding impact. Using field observations and GIS mapping techniques, we investigated how landscape factors influenced structural flooding impact in informal settlements. This study was carried out in the informal settlements of the Eastern Cape Province of South Africa, after the October 2012 floods. Increasing slope significantly raised the probability and level of damage by at least 30% in five of the seven sites, whereas proximity to river and wetlands (more than 100 m) was significant in only two of the sites and at lower levels. Multi-regression analysis highlighted that land cover, proximity to streams and household topographical location influenced the impact of flooding on housing structures. We found that the impact on housing structures in informal settlements during the floods were significantly influenced by their proximity to water bodies, slope factor and patterns of land cover.
- Full Text:
Informal urban fuelwood markets in South Africa in the context of socio-economic change
- Guild, J, Shackleton, Charlie M
- Authors: Guild, J , Shackleton, Charlie M
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/179779 , vital:43179 , xlink:href="https://doi.org/10.1016/j.enpol.2018.03.023"
- Description: In developing countries, fuelwood is important to livelihoods and energy security because it is used for heating, cooking and can provide additional income to households through trade. The global trade in fuelwood is valued between USD 4–26 billion per annum. In South Africa, fuelwood is a widely used domestic energy source; but how that has changed with rapid urbanisation and socio-economic development over the last two decades is unknown. This study examined the presence and nature of urban fuelwood markets in 39 urban areas of the Eastern Cape and Limpopo provinces. Data were collected from 170 informal fuelwood sellers regarding the prevalence, structure, characteristics, and changes over time of the informal fuelwood markets. Over 80% of the sampled towns had an informal fuelwood market and there was a positive relationship between the number of sellers and town population size. For most sellers, the fuelwood trade was their primary occupation and the income earned was supplemented by government social grants. Sellers earned, on average, over US$9 per day. These results show that despite rapid urbanisation and socio-economic development, fuelwood remains an important domestic fuel in towns and cities of South Africa, and an income source for the urban poor.
- Full Text:
- Authors: Guild, J , Shackleton, Charlie M
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/179779 , vital:43179 , xlink:href="https://doi.org/10.1016/j.enpol.2018.03.023"
- Description: In developing countries, fuelwood is important to livelihoods and energy security because it is used for heating, cooking and can provide additional income to households through trade. The global trade in fuelwood is valued between USD 4–26 billion per annum. In South Africa, fuelwood is a widely used domestic energy source; but how that has changed with rapid urbanisation and socio-economic development over the last two decades is unknown. This study examined the presence and nature of urban fuelwood markets in 39 urban areas of the Eastern Cape and Limpopo provinces. Data were collected from 170 informal fuelwood sellers regarding the prevalence, structure, characteristics, and changes over time of the informal fuelwood markets. Over 80% of the sampled towns had an informal fuelwood market and there was a positive relationship between the number of sellers and town population size. For most sellers, the fuelwood trade was their primary occupation and the income earned was supplemented by government social grants. Sellers earned, on average, over US$9 per day. These results show that despite rapid urbanisation and socio-economic development, fuelwood remains an important domestic fuel in towns and cities of South Africa, and an income source for the urban poor.
- Full Text:
Installation view: Chale Wote Festival 2018
- Authors: Simbao, Ruth K
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147059 , vital:38589 , https://www.contemporaryand.com/magazines/chale-wote-festival-accra-2018/
- Description: The Chale Wote festival opened on the Day of Re-Membering (20 August), when the Nai Priest poured libations at Brazil House in order to invoke the ancestral spirits. Core events took place on the streets and at various public spaces in James Town from 25 – 26 August. A number of artists including Kiffouly Youchaou, Kresiah Mukwazhi, Va-Bene Elikem Fiatsi (crazinisT artisT), Charlotte Brathwaite, Percy Nii Nortey and the Ubulungiswa/Justice collective created works inside Ussher Fort and James Fort, which were built as slave forts by the Dutch and the British.
- Full Text:
- Authors: Simbao, Ruth K
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147059 , vital:38589 , https://www.contemporaryand.com/magazines/chale-wote-festival-accra-2018/
- Description: The Chale Wote festival opened on the Day of Re-Membering (20 August), when the Nai Priest poured libations at Brazil House in order to invoke the ancestral spirits. Core events took place on the streets and at various public spaces in James Town from 25 – 26 August. A number of artists including Kiffouly Youchaou, Kresiah Mukwazhi, Va-Bene Elikem Fiatsi (crazinisT artisT), Charlotte Brathwaite, Percy Nii Nortey and the Ubulungiswa/Justice collective created works inside Ussher Fort and James Fort, which were built as slave forts by the Dutch and the British.
- Full Text:
Integrated genetic and morphological data support eco‐evolutionary divergence of Angolan and South African populations of Diplodus hottentotus
- Gwilliam, Michael P, Winkler, Alexander C, Potts, Warren M, Santos, Carmen V D, Sauer, Warwick H H, Shaw, Paul W, McKeown, Niall J
- Authors: Gwilliam, Michael P , Winkler, Alexander C , Potts, Warren M , Santos, Carmen V D , Sauer, Warwick H H , Shaw, Paul W , McKeown, Niall J
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124833 , vital:35702 , https://doi.10.1111/jfb.13582
- Description: The genus Diplodus presents multiple cases of taxonomic conjecture. Among these the D. cervinus complex was previously described as comprising three subspecies that are now regarded as separate species: Diplodus cervinus, Diplodus hottentotus and Diplodus omanensis. Diplodus hottentotus exhibits a clear break in its distribution around the Benguela Current system, prompting speculation that Angolan and South African populations flanking this area may be isolated and warrant formal taxonomic distinction. This study reports the first integrated genetic [mitochondrial (mt)DNA and nuclear microsatellite] and morphological (morphometric, meristic and colouration) study to assess patterns of divergence between populations in the two regions. High levels of cytonuclear divergence between the populations support a prolonged period of genetic isolation, with the sharing of only one mtDNA haplotype (12 haplotypes were fully sorted between regions) attributed to retention of ancestral polymorphism. Fish from the two regions were significantly differentiated at a number of morphometric (69·5%) and meristic (46%) characters. In addition, Angolan and South African fish exhibited reciprocally diagnostic colouration patterns that were more similar to Mediterranean and Indian Ocean congeners, respectively. Based on the congruent genetic and phenotypic diversity we suggest that the use of hottentotus, whether for full species or subspecies status, should be restricted to South African D. cervinus to reflect their status as a distinct species-like unit, while the relationship between Angolan and Atlantic–Mediterranean D. cervinus will require further demo-genetic analysis. This study highlights the utility of integrated genetic and morphological approaches to assess taxonomic diversity within the biogeographically dynamic Benguela Current region.
- Full Text:
- Authors: Gwilliam, Michael P , Winkler, Alexander C , Potts, Warren M , Santos, Carmen V D , Sauer, Warwick H H , Shaw, Paul W , McKeown, Niall J
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124833 , vital:35702 , https://doi.10.1111/jfb.13582
- Description: The genus Diplodus presents multiple cases of taxonomic conjecture. Among these the D. cervinus complex was previously described as comprising three subspecies that are now regarded as separate species: Diplodus cervinus, Diplodus hottentotus and Diplodus omanensis. Diplodus hottentotus exhibits a clear break in its distribution around the Benguela Current system, prompting speculation that Angolan and South African populations flanking this area may be isolated and warrant formal taxonomic distinction. This study reports the first integrated genetic [mitochondrial (mt)DNA and nuclear microsatellite] and morphological (morphometric, meristic and colouration) study to assess patterns of divergence between populations in the two regions. High levels of cytonuclear divergence between the populations support a prolonged period of genetic isolation, with the sharing of only one mtDNA haplotype (12 haplotypes were fully sorted between regions) attributed to retention of ancestral polymorphism. Fish from the two regions were significantly differentiated at a number of morphometric (69·5%) and meristic (46%) characters. In addition, Angolan and South African fish exhibited reciprocally diagnostic colouration patterns that were more similar to Mediterranean and Indian Ocean congeners, respectively. Based on the congruent genetic and phenotypic diversity we suggest that the use of hottentotus, whether for full species or subspecies status, should be restricted to South African D. cervinus to reflect their status as a distinct species-like unit, while the relationship between Angolan and Atlantic–Mediterranean D. cervinus will require further demo-genetic analysis. This study highlights the utility of integrated genetic and morphological approaches to assess taxonomic diversity within the biogeographically dynamic Benguela Current region.
- Full Text: