Highly efficient CCl bond cleavage and unprecedented CC bond cleavage of environmentally toxic DDT through molecular electrochemical catalysis
- Liang, Xu, Huang, Tingting, Li, Minzhi, Mack, John, Wildervanck, Martijn, Nyokong, Tebello, Zhu, Weihua
- Authors: Liang, Xu , Huang, Tingting , Li, Minzhi , Mack, John , Wildervanck, Martijn , Nyokong, Tebello , Zhu, Weihua
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188921 , vital:44798 , xlink:href="https://doi.org/10.1016/j.apcata.2017.07.026"
- Description: The electrocatalytic properties of a Co(II)octaalkoxyphthalocyanine complex (Co(II)Pc) with eight strongly electron-donating substituents provide the first example of the complete dechlorination of DDT through molecular electrocatalysis, rather than the use of metal electrodes which had been achieved previously. Interaction with a highly nucleophilic [Co(I)Pc]2− species results in rapid cleavage of the C(sp3) Cl, C(sp2) Cl and aromatic C(sp2) Cl bonds. Bis(p-chlorophenyl)methanone (BPCl2) is detected in high yield along with its full dechlorination product, diphenylmethanone (BP) and the conventional C Cl bond cleavage products, due to an unprecedented C C bond cleavage reaction that is followed by the formation of a C−O bond. Theoretical calculations are used to analyze trends in the electronic structure of the Co(II)octaalkoxyphthalocyanine complex that account for the efficiency of the C Cl bond cleavage reactions, and the reaction process and mechanism are analyzed in depth.
- Full Text:
- Date Issued: 2017
- Authors: Liang, Xu , Huang, Tingting , Li, Minzhi , Mack, John , Wildervanck, Martijn , Nyokong, Tebello , Zhu, Weihua
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188921 , vital:44798 , xlink:href="https://doi.org/10.1016/j.apcata.2017.07.026"
- Description: The electrocatalytic properties of a Co(II)octaalkoxyphthalocyanine complex (Co(II)Pc) with eight strongly electron-donating substituents provide the first example of the complete dechlorination of DDT through molecular electrocatalysis, rather than the use of metal electrodes which had been achieved previously. Interaction with a highly nucleophilic [Co(I)Pc]2− species results in rapid cleavage of the C(sp3) Cl, C(sp2) Cl and aromatic C(sp2) Cl bonds. Bis(p-chlorophenyl)methanone (BPCl2) is detected in high yield along with its full dechlorination product, diphenylmethanone (BP) and the conventional C Cl bond cleavage products, due to an unprecedented C C bond cleavage reaction that is followed by the formation of a C−O bond. Theoretical calculations are used to analyze trends in the electronic structure of the Co(II)octaalkoxyphthalocyanine complex that account for the efficiency of the C Cl bond cleavage reactions, and the reaction process and mechanism are analyzed in depth.
- Full Text:
- Date Issued: 2017
How compatible are urban livestock and urban green spaces and trees?: An assessment in a medium-sized South African town
- Shackleton, Charlie M, Guild, Jenny, Bromham, B, Impey, S, Jarrett, Mitchell, Ngubane, S, Steijl, K
- Authors: Shackleton, Charlie M , Guild, Jenny , Bromham, B , Impey, S , Jarrett, Mitchell , Ngubane, S , Steijl, K
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181048 , vital:43694 , xlink:href="https://doi.org/10.1080/19463138.2017.1314968"
- Description: Urban green spaces and trees provide multiple benefits to urban residents and the sustainability of cities. A poorly examined benefit is the provision of fodder to urban livestock. However, the presence and activities of livestock may be incompatible with other uses, although this has been little studied. We examined the impacts of livestock on trees and parks along a gradient of declining livestock density, complemented with a tree planting experiment to monitor damage. Neighbouring residents and park managers were interviewed regarding their perceptions of damage caused by livestock. The negative impacts on soil compaction, tree damage and death increased with increasing livestock densities. Thorny tree species were damaged significantly less (13 %) than non-thorny species (77 %), as were protected trees (25 %) relative to unprotected ones (65 %). There was more tree damage in public green spaces (PUGS) (54 %) than control sites (38 %). The majority of local residents felt that livestock should not be allowed in formal PUGS, and most urban park managers regarded livestock damage as a strong disincentive to plant trees. These results show the need for management of the trade-offs caused by livestock and greater appreciation of livestock as agents shaping aspects of PUGS.
- Full Text:
- Date Issued: 2017
- Authors: Shackleton, Charlie M , Guild, Jenny , Bromham, B , Impey, S , Jarrett, Mitchell , Ngubane, S , Steijl, K
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181048 , vital:43694 , xlink:href="https://doi.org/10.1080/19463138.2017.1314968"
- Description: Urban green spaces and trees provide multiple benefits to urban residents and the sustainability of cities. A poorly examined benefit is the provision of fodder to urban livestock. However, the presence and activities of livestock may be incompatible with other uses, although this has been little studied. We examined the impacts of livestock on trees and parks along a gradient of declining livestock density, complemented with a tree planting experiment to monitor damage. Neighbouring residents and park managers were interviewed regarding their perceptions of damage caused by livestock. The negative impacts on soil compaction, tree damage and death increased with increasing livestock densities. Thorny tree species were damaged significantly less (13 %) than non-thorny species (77 %), as were protected trees (25 %) relative to unprotected ones (65 %). There was more tree damage in public green spaces (PUGS) (54 %) than control sites (38 %). The majority of local residents felt that livestock should not be allowed in formal PUGS, and most urban park managers regarded livestock damage as a strong disincentive to plant trees. These results show the need for management of the trade-offs caused by livestock and greater appreciation of livestock as agents shaping aspects of PUGS.
- Full Text:
- Date Issued: 2017
Improved endoglucanase production and mycelial biomass of some ericoid fungi
- Adeoyo, Olusegun Richard, Pletschke, Brett I, Dames, Joanna F
- Authors: Adeoyo, Olusegun Richard , Pletschke, Brett I , Dames, Joanna F
- Date: 2017
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/61435 , vital:28026 , https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5209310/
- Description: Fungal species associated with ericaceous plant roots produce a number of enzymes and other bio-active metabolites in order to enhance survival of their host plants in natural environments. This study focussed on endoglucanase production from root associated ericoid mycorrhizal and dark septate endophytic fungal isolates. Out of the five fungal isolates screened, Leohumicola sp. (ChemRU330/PPRI 13195) had the highest relative enzyme activity and was tested along with isolates belonging to Hyloscyphaceae (EdRU083/PPRI 17284) and Leotiomycetes (EdRU002/PPRI 17261) for endoglucanase production under different pH and nutritional conditions that included: carbon sources, nitrogen sources and metal ions, at an optimum temperature of 28 °C. An optimal of pH 5.0 produced enzyme activity of 3.99, 2.18 and 4.31 (U/mg protein) for isolates EdRU083, EdRU002 and Leohumicola sp. respectively. Increased enzyme activities and improved mycelial biomass production were obtained in the presence of supplements such as potassium, sodium, glucose, maltose, cellobiose, tryptone and peptone. While NaFe-EDTA and Co2+ inhibited enzyme activity. The potential role of these fungi as a source of novel enzymes is an ongoing objective of this study.
- Full Text:
- Date Issued: 2017
- Authors: Adeoyo, Olusegun Richard , Pletschke, Brett I , Dames, Joanna F
- Date: 2017
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/61435 , vital:28026 , https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5209310/
- Description: Fungal species associated with ericaceous plant roots produce a number of enzymes and other bio-active metabolites in order to enhance survival of their host plants in natural environments. This study focussed on endoglucanase production from root associated ericoid mycorrhizal and dark septate endophytic fungal isolates. Out of the five fungal isolates screened, Leohumicola sp. (ChemRU330/PPRI 13195) had the highest relative enzyme activity and was tested along with isolates belonging to Hyloscyphaceae (EdRU083/PPRI 17284) and Leotiomycetes (EdRU002/PPRI 17261) for endoglucanase production under different pH and nutritional conditions that included: carbon sources, nitrogen sources and metal ions, at an optimum temperature of 28 °C. An optimal of pH 5.0 produced enzyme activity of 3.99, 2.18 and 4.31 (U/mg protein) for isolates EdRU083, EdRU002 and Leohumicola sp. respectively. Increased enzyme activities and improved mycelial biomass production were obtained in the presence of supplements such as potassium, sodium, glucose, maltose, cellobiose, tryptone and peptone. While NaFe-EDTA and Co2+ inhibited enzyme activity. The potential role of these fungi as a source of novel enzymes is an ongoing objective of this study.
- Full Text:
- Date Issued: 2017
Improved nonlinear optical behaviour of ball type indium (III) phthalocyanine linked to glutathione capped nanoparticles
- Nwaji, Njemuwa, Oluwole, David O, Mack, John, Louzada, Marcel, Khene, Samson M, Britton, Jonathan, Nyokong, Tebello
- Authors: Nwaji, Njemuwa , Oluwole, David O , Mack, John , Louzada, Marcel , Khene, Samson M , Britton, Jonathan , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/239654 , vital:50752 , xlink:href="https://doi.org/10.1016/j.dyepig.2017.01.066"
- Description: The synthesis of ball–type indium phthalocyanine (complex 4) and its covalent attachment to glutathione (GSH–) capped (Ag, Au, CdTeSe, CdTeSe/ZnO) nanoparticles are reported in this work. Furthermore, their photophysical and nonlinear optical behaviour were investigated. We observed a decrease in the fluorescence quantum yield with corresponding increase in the triplet quantum yield of the nanoconjugates in comparison to complex 4 alone. The reverse saturable absorption was found to be dependent on excited state absorption. The optical limiting threshold ranges from 0.40–0.78 (J/cm2). The nanoconjugate of the complex 4 with GSH–CdTeSe/ZnO (QD1) accounted for the most improved triplet state parameters and nonlinear optical behaviour in comparison to complex 4 and the other nanoconjugates studied in this work.
- Full Text:
- Date Issued: 2017
- Authors: Nwaji, Njemuwa , Oluwole, David O , Mack, John , Louzada, Marcel , Khene, Samson M , Britton, Jonathan , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/239654 , vital:50752 , xlink:href="https://doi.org/10.1016/j.dyepig.2017.01.066"
- Description: The synthesis of ball–type indium phthalocyanine (complex 4) and its covalent attachment to glutathione (GSH–) capped (Ag, Au, CdTeSe, CdTeSe/ZnO) nanoparticles are reported in this work. Furthermore, their photophysical and nonlinear optical behaviour were investigated. We observed a decrease in the fluorescence quantum yield with corresponding increase in the triplet quantum yield of the nanoconjugates in comparison to complex 4 alone. The reverse saturable absorption was found to be dependent on excited state absorption. The optical limiting threshold ranges from 0.40–0.78 (J/cm2). The nanoconjugate of the complex 4 with GSH–CdTeSe/ZnO (QD1) accounted for the most improved triplet state parameters and nonlinear optical behaviour in comparison to complex 4 and the other nanoconjugates studied in this work.
- Full Text:
- Date Issued: 2017
Improved photocatalytic degradation of Orange G using hybrid nanofibers
- Ledwaba, Mpho, Masilela, Nkosiphile, Nyokong, Tebello, Antunes, Edith M
- Authors: Ledwaba, Mpho , Masilela, Nkosiphile , Nyokong, Tebello , Antunes, Edith M
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/239632 , vital:50750 , xlink:href="https://doi.org/10.1007/s11051-017-3853-3"
- Description: Functionalised electrospun polyamide-6 (PA-6) nanofibres incorporating gadolinium oxide nanoparticles conjugated to zinc tetracarboxyphenoxy phthalocyanine (ZnTCPPc) as the sensitizer were prepared for the photocatalytic degradation of Orange G. Fibres incorporating the phthalocyanine alone or a mixture of the nanoparticles and phthalocyanine were also generated. The singlet oxygen-generating ability of the sensitizer was shown to be maintained within the fibre mat, with the singlet oxygen quantum yields increasing upon incorporation of the magnetic nanoparticles. Consequently, the rate of the photodegradation of Orange G was observed to increase with an increase in singlet oxygen quantum yield. A reduction in the half-lives for the functionalised nanofibres was recorded in the presence of the magnetic nanoparticles, indicating an improvement in the efficiency of the degradation process.
- Full Text:
- Date Issued: 2017
- Authors: Ledwaba, Mpho , Masilela, Nkosiphile , Nyokong, Tebello , Antunes, Edith M
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/239632 , vital:50750 , xlink:href="https://doi.org/10.1007/s11051-017-3853-3"
- Description: Functionalised electrospun polyamide-6 (PA-6) nanofibres incorporating gadolinium oxide nanoparticles conjugated to zinc tetracarboxyphenoxy phthalocyanine (ZnTCPPc) as the sensitizer were prepared for the photocatalytic degradation of Orange G. Fibres incorporating the phthalocyanine alone or a mixture of the nanoparticles and phthalocyanine were also generated. The singlet oxygen-generating ability of the sensitizer was shown to be maintained within the fibre mat, with the singlet oxygen quantum yields increasing upon incorporation of the magnetic nanoparticles. Consequently, the rate of the photodegradation of Orange G was observed to increase with an increase in singlet oxygen quantum yield. A reduction in the half-lives for the functionalised nanofibres was recorded in the presence of the magnetic nanoparticles, indicating an improvement in the efficiency of the degradation process.
- Full Text:
- Date Issued: 2017
Improvement of the pharmacological activity of menthol via enzymatic β-anomer-selective glycosylation
- Choi, Ha-Young, Kim, Bo-Min, Morgan, Abubaker M A, Kim, Joong Su, Kim, Won-Gon
- Authors: Choi, Ha-Young , Kim, Bo-Min , Morgan, Abubaker M A , Kim, Joong Su , Kim, Won-Gon
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67515 , vital:29106 , http://dx.doi.org/10.1186/s13568-017-0468-0
- Description: Publisher version , Menthol has a considerable cooling effect, but the use range of menthol is limited because of its extremely low solubility in water and inherent flavor. (−)-Menthol β-glucoside was determined to be more soluble in water (>27 times) than (−)-menthol α-glucoside; hence, β-anomer-selective glucosylation of menthol is necessary. The in vitro glycosylation of (−)-menthol by uridine diphosphate glycosyltransferase (BLC) from Bacillus licheniformis generated (−)-menthol β-glucoside and new (−)-menthol β-galactoside and (−)-menthol N-acetylglucosamine. The maximum conversion rate of menthol to (−)-menthol β-D-glucoside by BLC was found to be 58.9%. Importantly, (−)-menthol β-D-glucoside had a higher cooling effect and no flavor compared with menthol. In addition, (−)-menthol β-D-glucoside was determined to be a non-sensitizer in a skin allergy test in the human cell line activation test, whereas menthol was a sensitizer.
- Full Text:
- Date Issued: 2017
- Authors: Choi, Ha-Young , Kim, Bo-Min , Morgan, Abubaker M A , Kim, Joong Su , Kim, Won-Gon
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67515 , vital:29106 , http://dx.doi.org/10.1186/s13568-017-0468-0
- Description: Publisher version , Menthol has a considerable cooling effect, but the use range of menthol is limited because of its extremely low solubility in water and inherent flavor. (−)-Menthol β-glucoside was determined to be more soluble in water (>27 times) than (−)-menthol α-glucoside; hence, β-anomer-selective glucosylation of menthol is necessary. The in vitro glycosylation of (−)-menthol by uridine diphosphate glycosyltransferase (BLC) from Bacillus licheniformis generated (−)-menthol β-glucoside and new (−)-menthol β-galactoside and (−)-menthol N-acetylglucosamine. The maximum conversion rate of menthol to (−)-menthol β-D-glucoside by BLC was found to be 58.9%. Importantly, (−)-menthol β-D-glucoside had a higher cooling effect and no flavor compared with menthol. In addition, (−)-menthol β-D-glucoside was determined to be a non-sensitizer in a skin allergy test in the human cell line activation test, whereas menthol was a sensitizer.
- Full Text:
- Date Issued: 2017
Improving fold resistance prediction of HIV-1 against protease and reverse transcriptase inhibitors using artificial neural networks:
- Amamuddy, Olivier S, Bishop, Nigel T, Tastan Bishop, Özlem
- Authors: Amamuddy, Olivier S , Bishop, Nigel T , Tastan Bishop, Özlem
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148261 , vital:38724 , https://0-doi.org.wam.seals.ac.za/10.1186/s12859-017-1782-x
- Description: Drug resistance in HIV treatment is still a worldwide problem. Predicting resistance to antiretrovirals (ARVs) before starting any treatment is important. Prediction accuracy is essential, as low-accuracy predictions increase the risk of prescribing sub-optimal drug regimens leading to patients developing resistance sooner. Artificial Neural Networks (ANNs) are a powerful tool that would be able to assist in drug resistance prediction. In this study, we constrained the dataset to subtype B, sacrificing generalizability for a higher predictive performance, and demonstrated that the predictive quality of the ANN regression models have definite improvement for most ARVs.
- Full Text:
- Date Issued: 2017
- Authors: Amamuddy, Olivier S , Bishop, Nigel T , Tastan Bishop, Özlem
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148261 , vital:38724 , https://0-doi.org.wam.seals.ac.za/10.1186/s12859-017-1782-x
- Description: Drug resistance in HIV treatment is still a worldwide problem. Predicting resistance to antiretrovirals (ARVs) before starting any treatment is important. Prediction accuracy is essential, as low-accuracy predictions increase the risk of prescribing sub-optimal drug regimens leading to patients developing resistance sooner. Artificial Neural Networks (ANNs) are a powerful tool that would be able to assist in drug resistance prediction. In this study, we constrained the dataset to subtype B, sacrificing generalizability for a higher predictive performance, and demonstrated that the predictive quality of the ANN regression models have definite improvement for most ARVs.
- Full Text:
- Date Issued: 2017
Improving singlet oxygen generating abilities of phthalocyanines
- Nwahara, Nnamdi, Britton, Jonathan, Nyokong, Tebello
- Authors: Nwahara, Nnamdi , Britton, Jonathan , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188943 , vital:44800 , xlink:href="https://doi.org/10.1080/00958972.2017.1313975"
- Description: Glutathione-capped graphene quantum dots (GQDs@GSH) were covalently linked to folic acid (FA). Aluminum tetrasulfonated phthalocyanine (ClAlTSPc) was then adsorbed on the GQDs@GSH-FA conjugate to form GQDs@GSH-FA/ClAlTSPc or on GQDs@GSH and pristine GQDs alone to form GQDs@GSH/ClAlTSPc and GQDs/ClAlTSPc, respectively. We report for the first time on the photophysicochemical behavior of the resulting nanoconjugates. The fluorescence quantum yields of pristine GQDs, GQDS@GSH, or GQDs@GSH-FA conjugate were quenched upon non-covalent interaction (π–π) with ClAlTSPc. There was an increase in triplet quantum yields from 0.38 for ClAlTSPc alone to 0.60, 0.75, and 0.73 when ClAlTSPc was linked to pristine GQDs, GQDs@GSH, and GQDs@GSH-FA, respectively. The singlet oxygen quantum yields also increased from 0.37 for ClAlTSPc alone to 0.42 (for ClALTSPc with pristine GQDs), 0.52 (for ClAlTSPc with GQDs@GSH), and 0.54 (for ClAlTSPc with GQDs@GSH-FA). Thus, the present work may lead to a new generation of carbon-based nanomaterial photodynamic therapy agents with overall performance superior to conventional agents in terms of singlet oxygen generation, water dispersibility, and biocompatibility.
- Full Text:
- Date Issued: 2017
- Authors: Nwahara, Nnamdi , Britton, Jonathan , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188943 , vital:44800 , xlink:href="https://doi.org/10.1080/00958972.2017.1313975"
- Description: Glutathione-capped graphene quantum dots (GQDs@GSH) were covalently linked to folic acid (FA). Aluminum tetrasulfonated phthalocyanine (ClAlTSPc) was then adsorbed on the GQDs@GSH-FA conjugate to form GQDs@GSH-FA/ClAlTSPc or on GQDs@GSH and pristine GQDs alone to form GQDs@GSH/ClAlTSPc and GQDs/ClAlTSPc, respectively. We report for the first time on the photophysicochemical behavior of the resulting nanoconjugates. The fluorescence quantum yields of pristine GQDs, GQDS@GSH, or GQDs@GSH-FA conjugate were quenched upon non-covalent interaction (π–π) with ClAlTSPc. There was an increase in triplet quantum yields from 0.38 for ClAlTSPc alone to 0.60, 0.75, and 0.73 when ClAlTSPc was linked to pristine GQDs, GQDs@GSH, and GQDs@GSH-FA, respectively. The singlet oxygen quantum yields also increased from 0.37 for ClAlTSPc alone to 0.42 (for ClALTSPc with pristine GQDs), 0.52 (for ClAlTSPc with GQDs@GSH), and 0.54 (for ClAlTSPc with GQDs@GSH-FA). Thus, the present work may lead to a new generation of carbon-based nanomaterial photodynamic therapy agents with overall performance superior to conventional agents in terms of singlet oxygen generation, water dispersibility, and biocompatibility.
- Full Text:
- Date Issued: 2017
In conversation with Andrew Tshabangu and Thembinkosi Goniwe "Footprints" exhibition:
- Authors: Lila, Philiswa
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/146489 , vital:38530 , https://www.ru.ac.za/artsofafrica/exhibitionsperformances/inzwi/
- Description: Inzwi! was an art event during the 2017 National Arts Festival in Grahamstown that celebrated the 5th anniversary of the Lucid Lunchbox, a student-led series of talks linked to the Arts of Africa and Global Souths research programme at Rhodes University. During the festival, five sets composed of three videos interjected the talks presented by Dineo Seshee Bopape and Beth Diane Armstrong, as well as a conversation between Andrew Tshabangu, Thembinkosi Goniwe and Philiswa Lila. The event intended to trigger reflection and dialogue, through a ‘wake-up call’ to grapple with our collective heritage and struggles, our fears and points of departure in order to envision futures. The selection of videos drew from the work of Rhodes Fine Art students, Alumni and Artists in Residence. Works on display addressed matters of identity (social, political and/or fictional); social engagement and activism; religious and spiritual practices in African contexts; race and white supremacy; and, finally, patronising relations in the art world. Borrowing from the words of Weléla Mar Kindred, the choreography of this event, like others that have been propelling black body politics in recent movements, is one of "communal healing, strength and solidarity".
- Full Text:
- Date Issued: 2017
- Authors: Lila, Philiswa
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/146489 , vital:38530 , https://www.ru.ac.za/artsofafrica/exhibitionsperformances/inzwi/
- Description: Inzwi! was an art event during the 2017 National Arts Festival in Grahamstown that celebrated the 5th anniversary of the Lucid Lunchbox, a student-led series of talks linked to the Arts of Africa and Global Souths research programme at Rhodes University. During the festival, five sets composed of three videos interjected the talks presented by Dineo Seshee Bopape and Beth Diane Armstrong, as well as a conversation between Andrew Tshabangu, Thembinkosi Goniwe and Philiswa Lila. The event intended to trigger reflection and dialogue, through a ‘wake-up call’ to grapple with our collective heritage and struggles, our fears and points of departure in order to envision futures. The selection of videos drew from the work of Rhodes Fine Art students, Alumni and Artists in Residence. Works on display addressed matters of identity (social, political and/or fictional); social engagement and activism; religious and spiritual practices in African contexts; race and white supremacy; and, finally, patronising relations in the art world. Borrowing from the words of Weléla Mar Kindred, the choreography of this event, like others that have been propelling black body politics in recent movements, is one of "communal healing, strength and solidarity".
- Full Text:
- Date Issued: 2017
In vitro antimicrobial activity of the methanol extract and compounds from the wood of Ficus elastica Roxb. ex Hornem. aerial roots
- Meyer, Franck, Fannang, Simone Véronique, Noundou, Xavier Siwe, Krause, Rui W M, Teinkela, Jean Emmanuel Mbosso, Vardamides, Juliette Cathérine, Mpondo, Albert Emmanuel Mpondo, Azebaze, Anatole Guy Blaise, Nguedia, Jules Clément Assob
- Authors: Meyer, Franck , Fannang, Simone Véronique , Noundou, Xavier Siwe , Krause, Rui W M , Teinkela, Jean Emmanuel Mbosso , Vardamides, Juliette Cathérine , Mpondo, Albert Emmanuel Mpondo , Azebaze, Anatole Guy Blaise , Nguedia, Jules Clément Assob
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/126154 , vital:35854 , https://doi.org/10.1016/j.sajb.2017.03.026
- Description: Ficus elastica Roxb. ex Hornem., an edible plant belonging to the family of Moraceae, is traditionally used against skin infections and allergies besides having diuretic properties. This study aimed at investigating the antimicrobial activity of the wood of F. elastica aerial roots against a set of bacteria (Staphylococcus aureus; Escherichia coli, Proteus vulgaris, Providencia stuartii and Pseudomonas aeruginosa) and a yeast (Candida albicans). A mixture of linear aliphatic alkanes with n-hexacosane as major compound, β-sitosterol, biochanin A, sitosteryl 3-O-β-D-glucopyranoside (1), elasticamide (2), elastiquinone (3) and ficusoside B (4) were purified and characterized. Antimicrobial activities, expressed as minimum inhibitory concentration (MIC), indicated that the methanol extract showed MIC of 39.1 μg/mL; the lowest values were obtained for 3 and 4, with MIC as low as 4.9 μg/mL, smaller than the values of reference antibiotics (25 μg/mL). Furthermore, as most of the studied samples exhibited Minimum Microbicidal Concentration/Minimum Inhibitory Concentration (MMC/MIC) ratios lower than 4, a microbicidal effect was clearly exhibited. The overall results provided evidence that the wood of F. elastica aerial roots, as well as some of its isolated components might be potential sources of new antimicrobial drugs.
- Full Text:
- Date Issued: 2017
- Authors: Meyer, Franck , Fannang, Simone Véronique , Noundou, Xavier Siwe , Krause, Rui W M , Teinkela, Jean Emmanuel Mbosso , Vardamides, Juliette Cathérine , Mpondo, Albert Emmanuel Mpondo , Azebaze, Anatole Guy Blaise , Nguedia, Jules Clément Assob
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/126154 , vital:35854 , https://doi.org/10.1016/j.sajb.2017.03.026
- Description: Ficus elastica Roxb. ex Hornem., an edible plant belonging to the family of Moraceae, is traditionally used against skin infections and allergies besides having diuretic properties. This study aimed at investigating the antimicrobial activity of the wood of F. elastica aerial roots against a set of bacteria (Staphylococcus aureus; Escherichia coli, Proteus vulgaris, Providencia stuartii and Pseudomonas aeruginosa) and a yeast (Candida albicans). A mixture of linear aliphatic alkanes with n-hexacosane as major compound, β-sitosterol, biochanin A, sitosteryl 3-O-β-D-glucopyranoside (1), elasticamide (2), elastiquinone (3) and ficusoside B (4) were purified and characterized. Antimicrobial activities, expressed as minimum inhibitory concentration (MIC), indicated that the methanol extract showed MIC of 39.1 μg/mL; the lowest values were obtained for 3 and 4, with MIC as low as 4.9 μg/mL, smaller than the values of reference antibiotics (25 μg/mL). Furthermore, as most of the studied samples exhibited Minimum Microbicidal Concentration/Minimum Inhibitory Concentration (MMC/MIC) ratios lower than 4, a microbicidal effect was clearly exhibited. The overall results provided evidence that the wood of F. elastica aerial roots, as well as some of its isolated components might be potential sources of new antimicrobial drugs.
- Full Text:
- Date Issued: 2017
Incidence of unnatural deaths in Transkei subregion of South Africa (1996 –2015)
- Date: 2017
- Subjects: South Africa Death 2078-6204 Journal article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6172 , vital:45258 , xlink:href=": https://doi.org/10.1080/20786190.2017.1292697"
- Description: Background: Unnatural deaths are a serious and preventable public health problem in South Africa. Such an event is more than the death of an individual who has died in an unnatural way. It has a negative and long-lasting impact on family members as well as on society as a whole. Objective: To study the pattern of unnatural deaths in the Transkei sub-region of South Africa. Method: A record review was undertaken from 1996 to 2015 of 24 693 medico-legal autopsies performed at Mthatha Forensic Pathology Laboratory. Results: At the Mthatha Forensic Pathology Laboratory, 24 693 autopsies were performed between 1996 and 2015 on people who had died unnatural deaths. The average rate of unnatural death is 205 per 100 000 per year in this region. The figure is 160 per 100 000 among males and 44 per 100 000 among females. The rate of unnatural death has increased from 153 per 100 000 in 1996 to 260 per 100 000 in 2015. In two-thirds (69%) of cases, the cause of death is related to trauma. Slightly less than half (45%) of the victims in this study were murdered. Conclusion: There is an increasing trend of unnatural deaths in the Mthatha region of South Africa. The male-to-female ratio is 3.8:1, and about half (48%) of the victims were between 11 and 30 years old. This situation needs the urgent attention of the law enforcement agencies. Keywords: unnatural deaths, traumatic deaths, violent death
- Full Text:
- Date Issued: 2017
- Date: 2017
- Subjects: South Africa Death 2078-6204 Journal article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6172 , vital:45258 , xlink:href=": https://doi.org/10.1080/20786190.2017.1292697"
- Description: Background: Unnatural deaths are a serious and preventable public health problem in South Africa. Such an event is more than the death of an individual who has died in an unnatural way. It has a negative and long-lasting impact on family members as well as on society as a whole. Objective: To study the pattern of unnatural deaths in the Transkei sub-region of South Africa. Method: A record review was undertaken from 1996 to 2015 of 24 693 medico-legal autopsies performed at Mthatha Forensic Pathology Laboratory. Results: At the Mthatha Forensic Pathology Laboratory, 24 693 autopsies were performed between 1996 and 2015 on people who had died unnatural deaths. The average rate of unnatural death is 205 per 100 000 per year in this region. The figure is 160 per 100 000 among males and 44 per 100 000 among females. The rate of unnatural death has increased from 153 per 100 000 in 1996 to 260 per 100 000 in 2015. In two-thirds (69%) of cases, the cause of death is related to trauma. Slightly less than half (45%) of the victims in this study were murdered. Conclusion: There is an increasing trend of unnatural deaths in the Mthatha region of South Africa. The male-to-female ratio is 3.8:1, and about half (48%) of the victims were between 11 and 30 years old. This situation needs the urgent attention of the law enforcement agencies. Keywords: unnatural deaths, traumatic deaths, violent death
- Full Text:
- Date Issued: 2017
Integrating biodiversity considerations into urban golf courses: Managers’ perceptions and woody plant diversity in the Eastern Cape, South Africa
- Jarrett, Mitchell, Shackleton, Charlie M
- Authors: Jarrett, Mitchell , Shackleton, Charlie M
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180353 , vital:43356 , xlink:href="https://doi.org/10.1080/1747423X.2017.1325525"
- Description: Rapid rates of urbanisation affect biodiversity through habitat fragmentation and loss. Because urban golf courses are large green spaces, they potentially harbour much biodiversity if managed for such. The area of untransformed land of golf courses in the Eastern Cape (South Africa) was determined using Geographic Information System (GIS), the woody plant composition of a subsample was determined by field sampling and the greenkeepers were interviewed. There was a significant relationship between climate and woody cover, species richness and percentage native plants but not species diversity. There was no relationship between management scores and species richness, diversity and percentage native. Significant relationships were evident between woody plant species richness and course income, number of grounds staff, number of club members and greenkeepers’ years of experience. These results suggest a complex suite of factors that play a role in the woody plant composition of urban golf courses and their contribution to urban biodiversity.
- Full Text:
- Date Issued: 2017
- Authors: Jarrett, Mitchell , Shackleton, Charlie M
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180353 , vital:43356 , xlink:href="https://doi.org/10.1080/1747423X.2017.1325525"
- Description: Rapid rates of urbanisation affect biodiversity through habitat fragmentation and loss. Because urban golf courses are large green spaces, they potentially harbour much biodiversity if managed for such. The area of untransformed land of golf courses in the Eastern Cape (South Africa) was determined using Geographic Information System (GIS), the woody plant composition of a subsample was determined by field sampling and the greenkeepers were interviewed. There was a significant relationship between climate and woody cover, species richness and percentage native plants but not species diversity. There was no relationship between management scores and species richness, diversity and percentage native. Significant relationships were evident between woody plant species richness and course income, number of grounds staff, number of club members and greenkeepers’ years of experience. These results suggest a complex suite of factors that play a role in the woody plant composition of urban golf courses and their contribution to urban biodiversity.
- Full Text:
- Date Issued: 2017
Intellectualisation of isiXhosa literature: the case of Jeff Opland
- Authors: Kaschula, Russell H
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67030 , vital:29022 , https://doi.org/10.17159/2309-9070/tvl.v.54i2.413
- Description: publisher version , The origins of the intellectualisation of written isiXhosa literature are often attributed to the missionaries John Ross and John Bennie. They set up a printing press in the Tyhume Valley which later became known as Lovedale Press. They introduced written isiXhosa in 1823 and for this they are acknowledged as the first to write and publish in isiXhosa. This article attempts to trace this intellectualisation process of isiXhosa literature, concentrating on a critique and assessment of the life-long work of Professor Jeff Opland, who has contributed enormously to the present understanding of both oral and written isiXhosa literature. It is argued in this article that his corpus of books and academic articles require some contextualisation within the broader debate of the continued intellectualisation of isiXhosa language and literature. Reference is also made to the Opland isiXhosa literature archive and its contribution to the further intellectualisation of isiXhosa literature. It is suggested in this article that Opland is one of the greatest contributors to academic debates concerning isiXhosa literature and history. Izibongo or oral poems written by, and about Jeff Opland are analysed to further enhance the context of his contribution.
- Full Text:
- Date Issued: 2017
- Authors: Kaschula, Russell H
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67030 , vital:29022 , https://doi.org/10.17159/2309-9070/tvl.v.54i2.413
- Description: publisher version , The origins of the intellectualisation of written isiXhosa literature are often attributed to the missionaries John Ross and John Bennie. They set up a printing press in the Tyhume Valley which later became known as Lovedale Press. They introduced written isiXhosa in 1823 and for this they are acknowledged as the first to write and publish in isiXhosa. This article attempts to trace this intellectualisation process of isiXhosa literature, concentrating on a critique and assessment of the life-long work of Professor Jeff Opland, who has contributed enormously to the present understanding of both oral and written isiXhosa literature. It is argued in this article that his corpus of books and academic articles require some contextualisation within the broader debate of the continued intellectualisation of isiXhosa language and literature. Reference is also made to the Opland isiXhosa literature archive and its contribution to the further intellectualisation of isiXhosa literature. It is suggested in this article that Opland is one of the greatest contributors to academic debates concerning isiXhosa literature and history. Izibongo or oral poems written by, and about Jeff Opland are analysed to further enhance the context of his contribution.
- Full Text:
- Date Issued: 2017
Interacting motif networks located in hotspots associated with RNA release are conserved in Enterovirus capsids
- Ross, Caroline J, Knox, Caroline M, Tastan Bishop, Özlem
- Authors: Ross, Caroline J , Knox, Caroline M , Tastan Bishop, Özlem
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124855 , vital:35704 , https://doi.10.1002/1873-3468.12663
- Description: Enteroviruses are responsible for a multitude of human diseases. Expansion of the virus capsid is associated with a cascade of conformational changes that allow the subsequent release of RNA. For the first time, this study presents a comprehensive bioinformatic screen for the prediction of interacting motifs within intraprotomer interfaces and across respective interfaces surrounding the fivefold and twofold axes. The results identify a network of conserved motif residues involved in interactions in enteroviruses that may be critical to capsid stabilisation, providing guidelines towards developing antivirals that interfere with viral expansion during RNA release.
- Full Text:
- Date Issued: 2017
- Authors: Ross, Caroline J , Knox, Caroline M , Tastan Bishop, Özlem
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124855 , vital:35704 , https://doi.10.1002/1873-3468.12663
- Description: Enteroviruses are responsible for a multitude of human diseases. Expansion of the virus capsid is associated with a cascade of conformational changes that allow the subsequent release of RNA. For the first time, this study presents a comprehensive bioinformatic screen for the prediction of interacting motifs within intraprotomer interfaces and across respective interfaces surrounding the fivefold and twofold axes. The results identify a network of conserved motif residues involved in interactions in enteroviruses that may be critical to capsid stabilisation, providing guidelines towards developing antivirals that interfere with viral expansion during RNA release.
- Full Text:
- Date Issued: 2017
Interrogating citizen journalism practices: a case study of Rhodes University’s Lindaba Ziyafika Project
- Nyathi, Sihle, Garman, Anthea
- Authors: Nyathi, Sihle , Garman, Anthea
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/158915 , vital:40240 , https://doi.org/10.1080/23743670.2016.1259740
- Description: Several scholars have noted that citizen journalism in the West is essentially an online phenomenon, driven by the affordability of Internet technologies. In Africa, projects such as Ushahidi in Kenya have been enabled by platforms such as cell phones and social networks. Voices of Africa, based in southern Africa, publishes on the web only. Publishing on the Internet presumes a citizenry which is relatively well educated; has familiarity with, and access to, new media as a form of social communication; and is confident in their right to participate in newly developed public spheres – particularly those online.
- Full Text:
- Date Issued: 2017
- Authors: Nyathi, Sihle , Garman, Anthea
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/158915 , vital:40240 , https://doi.org/10.1080/23743670.2016.1259740
- Description: Several scholars have noted that citizen journalism in the West is essentially an online phenomenon, driven by the affordability of Internet technologies. In Africa, projects such as Ushahidi in Kenya have been enabled by platforms such as cell phones and social networks. Voices of Africa, based in southern Africa, publishes on the web only. Publishing on the Internet presumes a citizenry which is relatively well educated; has familiarity with, and access to, new media as a form of social communication; and is confident in their right to participate in newly developed public spheres – particularly those online.
- Full Text:
- Date Issued: 2017
Investigation of photophysicochemical properties of zinc phthalocyanines conjugated to metallic nanoparticles
- Dube, Edith, Nwaji, Njemuwa, Oluwole, David O, Mack, John, Nyokong, Tebello
- Authors: Dube, Edith , Nwaji, Njemuwa , Oluwole, David O , Mack, John , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/233425 , vital:50089 , xlink:href="https://doi.org/10.1016/j.jphotochem.2017.09.020"
- Description: The syntheses of zinc(II) tetra–[3–(4–phenoxy) (propanoic acid) phthalocyanine] (2) and zinc(II) mono–[3–(4–phenoxy) (propanoic acid) phthalocyanine (3) are reported in this work. Compounds 2 and 3 were covalently linked to glutathione capped silver (AgNPs–GSH), gold (AuNPs–GSH) and silver-gold alloy (Ag3Au1NPs–GSH) nanoparticles (NPs) via an amide bond formation to afford the conjugates: 2–AgNPs–GSH, 3–AgNPs–GSH, 2–AuNPs–GSH, 3–AuNPs–GSH, 2-Ag3Au1NPs–GSH and 3-Ag3Au1NPs–GSH. The photophysicochemical behaviours of the compounds and their conjugates with NPs were assessed in solution. The conjugates afforded a decrease in fluorescence quantum yields and lifetimes with improved triplet quantum yields in comparison to the compounds. Accordingly, the AgNPs and AuNPs conjugates with the compounds afforded high singlet quantum yields. On the contrary, the conjugates of the alloy afforded decreased singlet quantum yields probably due to the screening effect. The compounds and their conjugates with NPs could serve as a viable and efficacious photosensitizer for photodynamic therapy.
- Full Text:
- Date Issued: 2017
- Authors: Dube, Edith , Nwaji, Njemuwa , Oluwole, David O , Mack, John , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/233425 , vital:50089 , xlink:href="https://doi.org/10.1016/j.jphotochem.2017.09.020"
- Description: The syntheses of zinc(II) tetra–[3–(4–phenoxy) (propanoic acid) phthalocyanine] (2) and zinc(II) mono–[3–(4–phenoxy) (propanoic acid) phthalocyanine (3) are reported in this work. Compounds 2 and 3 were covalently linked to glutathione capped silver (AgNPs–GSH), gold (AuNPs–GSH) and silver-gold alloy (Ag3Au1NPs–GSH) nanoparticles (NPs) via an amide bond formation to afford the conjugates: 2–AgNPs–GSH, 3–AgNPs–GSH, 2–AuNPs–GSH, 3–AuNPs–GSH, 2-Ag3Au1NPs–GSH and 3-Ag3Au1NPs–GSH. The photophysicochemical behaviours of the compounds and their conjugates with NPs were assessed in solution. The conjugates afforded a decrease in fluorescence quantum yields and lifetimes with improved triplet quantum yields in comparison to the compounds. Accordingly, the AgNPs and AuNPs conjugates with the compounds afforded high singlet quantum yields. On the contrary, the conjugates of the alloy afforded decreased singlet quantum yields probably due to the screening effect. The compounds and their conjugates with NPs could serve as a viable and efficacious photosensitizer for photodynamic therapy.
- Full Text:
- Date Issued: 2017
Isolation, characterization and antiproliferative activity of new metabolites from the South African endemic red algal species Laurencia alfredensis
- Dziwornu, Godwin A, Caira, Mino R, de la Mare, Jo-Anne, Edkins, Adrienne L, Bolton, John J, Beukes, Denzil R, Sunassee, Suthananda N
- Authors: Dziwornu, Godwin A , Caira, Mino R , de la Mare, Jo-Anne , Edkins, Adrienne L , Bolton, John J , Beukes, Denzil R , Sunassee, Suthananda N
- Date: 2017
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59963 , vital:27715 , https://doi:10.3390/molecules22040513
- Description: The marine red algae of the genus Laurencia have been widely studied for their structurally diverse and biologically active secondary metabolites. We report here the natural product investigation of the organic extract of a newly identified South African endemic species, Laurencia alfredensis. A sequence of column chromatography, preparative TLC and normal phase HPLC resulted in the isolation of eleven compounds comprising three labdane-type diterpenes (1-3), four polyether triterpenes (4-7), three cholestane-type ecdysteroids (8-10) and a glycolipid (11). Compounds 1-3, 5-8 and 10 have not previously been reported, while compound 9 is reported here for the first time from a natural source and the known compound 11 isolated for the first time from the genus Laurencia. The structural elucidation and the relative configuration assignments of the compounds were accomplished by extensive use of ID- and 2D-NMR, HR-ESI-MS, UV and IR spectroscopic techniques, while the absolute configuration of compound 1 was determined by single-crystal X-ray diffraction analysis. All compounds were evaluated against the MDA-MB-231 breast and HeLa cervical cancer cell lines. Compound 2 exhibited low micromolar antiproliferative activity (IC50 = 9.3 gM) against the triple negative breast carcinoma and compound 7 was similarly active (IC50 = 8.8 gM) against the cervical cancer cell line.
- Full Text:
- Date Issued: 2017
- Authors: Dziwornu, Godwin A , Caira, Mino R , de la Mare, Jo-Anne , Edkins, Adrienne L , Bolton, John J , Beukes, Denzil R , Sunassee, Suthananda N
- Date: 2017
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59963 , vital:27715 , https://doi:10.3390/molecules22040513
- Description: The marine red algae of the genus Laurencia have been widely studied for their structurally diverse and biologically active secondary metabolites. We report here the natural product investigation of the organic extract of a newly identified South African endemic species, Laurencia alfredensis. A sequence of column chromatography, preparative TLC and normal phase HPLC resulted in the isolation of eleven compounds comprising three labdane-type diterpenes (1-3), four polyether triterpenes (4-7), three cholestane-type ecdysteroids (8-10) and a glycolipid (11). Compounds 1-3, 5-8 and 10 have not previously been reported, while compound 9 is reported here for the first time from a natural source and the known compound 11 isolated for the first time from the genus Laurencia. The structural elucidation and the relative configuration assignments of the compounds were accomplished by extensive use of ID- and 2D-NMR, HR-ESI-MS, UV and IR spectroscopic techniques, while the absolute configuration of compound 1 was determined by single-crystal X-ray diffraction analysis. All compounds were evaluated against the MDA-MB-231 breast and HeLa cervical cancer cell lines. Compound 2 exhibited low micromolar antiproliferative activity (IC50 = 9.3 gM) against the triple negative breast carcinoma and compound 7 was similarly active (IC50 = 8.8 gM) against the cervical cancer cell line.
- Full Text:
- Date Issued: 2017
Isolation, identification and genetic characterisation of a microsporidium isolated from carob moth, Ectomyelois ceratoniae (Zeller) (Lepidoptera: Pyralidae)
- Lloyd, Melissa, Knox, Caroline M, Hill, Martin P, Moore, Sean D
- Authors: Lloyd, Melissa , Knox, Caroline M , Hill, Martin P , Moore, Sean D
- Date: 2017
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59874 , vital:27674 , https://doi.org/10.4001/003.025.0529
- Description: 'Microsporidia' is a term used for organisms belonging to the phylum Microspora, which contains approximately 187 genera and 1500 species (Corradi 2015). They are obligate intracellular parasites with no active metabolic stages of the life cycle occurring outside of the host cells (Franzen & Muller 1999; Garcia 2002; Tsai et al. 2003; Huang et al. 2004). They exhibit eukaryotic characteristics such as a membrane-bound nucleus, an intracytoplasmic membrane system, and chromosome separation occurs on mitotic spindles. However, they also exhibit prokaryotic characteristics such as possession of a 70S ribosome, lack of true mitochondria and peroxisomes, a simple version of the Golgi apparatus, and a small genome which is much less complex than those of most eukaryotes (Franzen & Muller 1999; Garcia 2002). Microspo- ridia are parasitic in all major groups of animals, both vertebrates and invertebrates (Sprague 1977; Franzen & Muller 1999). Microsporidia were first recognised as pathogens in silkworms by Nageli (1857), and now have been found to infect many hosts such as humans, insects, fish and mammals (Stentiford et al. 2016).
- Full Text:
- Date Issued: 2017
- Authors: Lloyd, Melissa , Knox, Caroline M , Hill, Martin P , Moore, Sean D
- Date: 2017
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59874 , vital:27674 , https://doi.org/10.4001/003.025.0529
- Description: 'Microsporidia' is a term used for organisms belonging to the phylum Microspora, which contains approximately 187 genera and 1500 species (Corradi 2015). They are obligate intracellular parasites with no active metabolic stages of the life cycle occurring outside of the host cells (Franzen & Muller 1999; Garcia 2002; Tsai et al. 2003; Huang et al. 2004). They exhibit eukaryotic characteristics such as a membrane-bound nucleus, an intracytoplasmic membrane system, and chromosome separation occurs on mitotic spindles. However, they also exhibit prokaryotic characteristics such as possession of a 70S ribosome, lack of true mitochondria and peroxisomes, a simple version of the Golgi apparatus, and a small genome which is much less complex than those of most eukaryotes (Franzen & Muller 1999; Garcia 2002). Microspo- ridia are parasitic in all major groups of animals, both vertebrates and invertebrates (Sprague 1977; Franzen & Muller 1999). Microsporidia were first recognised as pathogens in silkworms by Nageli (1857), and now have been found to infect many hosts such as humans, insects, fish and mammals (Stentiford et al. 2016).
- Full Text:
- Date Issued: 2017
Journal development, scholar development and quality
- Rosenberg, Eureta, Togo, Muchaiteyi
- Authors: Rosenberg, Eureta , Togo, Muchaiteyi
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67314 , vital:29072 , https://doi.org/10.4314/SAJEE.V.33I1.1
- Description: publisher version , In reflecting on the contributions to Volume 33, it is evident that a variety of theories about learning and social change inform the scholars in environmental education, ranging from behaviourist, to social behavioural, constructivist and social constructivist learning theories, social and critical realism, and more. What unites these papers is a shared concern about learning in relation to the future well-being of the planet and its people. New scholars entering the field of environmental and sustainability education have the task of mastering not only the social– ecological subject matter of the field, but also their chosen learning theories. In this regard, drawing on the back copies of the SAJEE can be of great value. Much research and writing has already been done on curriculum, education and learning inside and outside of formal institutions, yet many more questions remain. The field is best advanced by noting and building on, challenging and advancing past studies and existing scholarship. The fact that all 33 Volumes of the SAJEE are available online, just a ‘few clicks away’ from any student or supervisor with Internet access, is therefore an enormous boon. We encourage readers and future authors to draw on the work in this and other environmental education journals as they conceptualise, design and reflect on their own studies.
- Full Text:
- Date Issued: 2017
- Authors: Rosenberg, Eureta , Togo, Muchaiteyi
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67314 , vital:29072 , https://doi.org/10.4314/SAJEE.V.33I1.1
- Description: publisher version , In reflecting on the contributions to Volume 33, it is evident that a variety of theories about learning and social change inform the scholars in environmental education, ranging from behaviourist, to social behavioural, constructivist and social constructivist learning theories, social and critical realism, and more. What unites these papers is a shared concern about learning in relation to the future well-being of the planet and its people. New scholars entering the field of environmental and sustainability education have the task of mastering not only the social– ecological subject matter of the field, but also their chosen learning theories. In this regard, drawing on the back copies of the SAJEE can be of great value. Much research and writing has already been done on curriculum, education and learning inside and outside of formal institutions, yet many more questions remain. The field is best advanced by noting and building on, challenging and advancing past studies and existing scholarship. The fact that all 33 Volumes of the SAJEE are available online, just a ‘few clicks away’ from any student or supervisor with Internet access, is therefore an enormous boon. We encourage readers and future authors to draw on the work in this and other environmental education journals as they conceptualise, design and reflect on their own studies.
- Full Text:
- Date Issued: 2017
Journal Development, Scholar Development and Quality
- Rosenberg, Eureta, Togo, Muchaiteyi
- Authors: Rosenberg, Eureta , Togo, Muchaiteyi
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/127235 , vital:35980 , https://doi.org/10.4314/sajee.v.33i1.1
- Description: Recently, the 33-year journey of the Southern African Journal of Environmental Education (SAJEE) was the subject of reflection during an Open Access Publishing week convened by Rhodes University Library Services. Two former and current editors-in-chief shared the SAJEE’s story of publishing ‘from the margins into the centre’. In the early 1990s, the Journal was mailed to the Environmental Education Association of Southern Africa (EEASA) membership from the foyer of the Rhodes Education Department (which had the floor space for stuffing and stacking A4 envelopes). In the first decade of this century, the Journal arrived at a symbolic ‘centre’ with digital distribution, first on the EEASA website and then from the Open Access platform provided by African Journals Online (AJOL). The digital move was vital for sustained and increased distribution in a time of shrinking budgets and growing costs. The results, shared with the EEASA Council earlier this year, were nothing short of spectacular: In March 2017, the SAJEE received more than 1 250 article downloads (www.ajol.info/index.php/sajee), and the number of downloads have stayed above 500 each month subsequently (Figure 1). Views and downloads are recorded around the world including,
- Full Text:
- Date Issued: 2017
- Authors: Rosenberg, Eureta , Togo, Muchaiteyi
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/127235 , vital:35980 , https://doi.org/10.4314/sajee.v.33i1.1
- Description: Recently, the 33-year journey of the Southern African Journal of Environmental Education (SAJEE) was the subject of reflection during an Open Access Publishing week convened by Rhodes University Library Services. Two former and current editors-in-chief shared the SAJEE’s story of publishing ‘from the margins into the centre’. In the early 1990s, the Journal was mailed to the Environmental Education Association of Southern Africa (EEASA) membership from the foyer of the Rhodes Education Department (which had the floor space for stuffing and stacking A4 envelopes). In the first decade of this century, the Journal arrived at a symbolic ‘centre’ with digital distribution, first on the EEASA website and then from the Open Access platform provided by African Journals Online (AJOL). The digital move was vital for sustained and increased distribution in a time of shrinking budgets and growing costs. The results, shared with the EEASA Council earlier this year, were nothing short of spectacular: In March 2017, the SAJEE received more than 1 250 article downloads (www.ajol.info/index.php/sajee), and the number of downloads have stayed above 500 each month subsequently (Figure 1). Views and downloads are recorded around the world including,
- Full Text:
- Date Issued: 2017