Mulch tower treatment system Part I: Overall performance in greywater treatment
- Zuma, Bongumusa M, Tandlich, Roman, Whittington-Jones, Kevin J, Burgess, Jo E
- Authors: Zuma, Bongumusa M , Tandlich, Roman , Whittington-Jones, Kevin J , Burgess, Jo E
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71537 , vital:29862 , https://doi.org/10.1016/j.desal.2008.03.030
- Description: A mulch tower (MT) system for greywater treatment is introduced in this paper. Materials used to assemble the MT system included mulch, coarse sand, fine and coarse gravel. Limited removal efficiency of the MT system was demonstrated for alkalinity, total hardness, pH, Cl–, PO43–, NH4+, and SO42–, with the estimated cumulative removals ranging from 7 to 12%. Intermediate removal efficiency was observed for chemical oxygen demand (COD), NO3–, and S2– with the estimated cumulative removals ranging from 24 to 28%. The highest removal efficiency was observed for the total suspended solids (TSS) with the estimated cumulative removal equal to 52%. Given the minute residence time in the MT system, the results obtained were promising and justify scale-up studies for potential on-site applications. The MT effluent did not meet hygienic norms with respect to the faecal coliform concentration (FC) and the total coliform concentration (TC), and further effluent treatment is required before any discharge or reuse of the treated greywater. Further research should focus on characterisation of the microbial community of the MT, and the fate of Cl–, PO43–, NH4+, and SO42–.
- Full Text: false
- Date Issued: 2009
- Authors: Zuma, Bongumusa M , Tandlich, Roman , Whittington-Jones, Kevin J , Burgess, Jo E
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71537 , vital:29862 , https://doi.org/10.1016/j.desal.2008.03.030
- Description: A mulch tower (MT) system for greywater treatment is introduced in this paper. Materials used to assemble the MT system included mulch, coarse sand, fine and coarse gravel. Limited removal efficiency of the MT system was demonstrated for alkalinity, total hardness, pH, Cl–, PO43–, NH4+, and SO42–, with the estimated cumulative removals ranging from 7 to 12%. Intermediate removal efficiency was observed for chemical oxygen demand (COD), NO3–, and S2– with the estimated cumulative removals ranging from 24 to 28%. The highest removal efficiency was observed for the total suspended solids (TSS) with the estimated cumulative removal equal to 52%. Given the minute residence time in the MT system, the results obtained were promising and justify scale-up studies for potential on-site applications. The MT effluent did not meet hygienic norms with respect to the faecal coliform concentration (FC) and the total coliform concentration (TC), and further effluent treatment is required before any discharge or reuse of the treated greywater. Further research should focus on characterisation of the microbial community of the MT, and the fate of Cl–, PO43–, NH4+, and SO42–.
- Full Text: false
- Date Issued: 2009
Synthesis, structure and in vitro anti-trypanosomal activity of non-toxic Arylpyrrole-Based Chalcone derivatives:
- Zulu, Ayanda I, Oderinlo, Ogunyemi O, Kruger, Cuan, Isaacs, Michelle, Hoppe, Heinrich C, Smith, Vincent J, Veale, Clinton G L, Khanye, Setshaba D
- Authors: Zulu, Ayanda I , Oderinlo, Ogunyemi O , Kruger, Cuan , Isaacs, Michelle , Hoppe, Heinrich C , Smith, Vincent J , Veale, Clinton G L , Khanye, Setshaba D
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/179017 , vital:40096 , https://doi.org/10.3390/molecules25071668
- Description: With an intention of identifying chalcone derivatives exhibiting anti-protozoal activity, a cohort of relatively unexplored arylpyrrole-based chalcone derivatives were synthesized in moderate to good yields. The resultant compounds were evaluated in vitro for their potential activity against a cultured Trypanosoma brucei brucei 427 strain. Several compounds displayed mostly modest in vitro anti-trypanosomal activity with compounds 10e and 10h emerging as active candidates with IC50 values of 4.09 and 5.11 µM, respectively. More importantly, a concomitant assessment of their activity against a human cervix adenocarcinoma (HeLa) cell line revealed that these compounds are non-toxic.
- Full Text:
- Date Issued: 2020
- Authors: Zulu, Ayanda I , Oderinlo, Ogunyemi O , Kruger, Cuan , Isaacs, Michelle , Hoppe, Heinrich C , Smith, Vincent J , Veale, Clinton G L , Khanye, Setshaba D
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/179017 , vital:40096 , https://doi.org/10.3390/molecules25071668
- Description: With an intention of identifying chalcone derivatives exhibiting anti-protozoal activity, a cohort of relatively unexplored arylpyrrole-based chalcone derivatives were synthesized in moderate to good yields. The resultant compounds were evaluated in vitro for their potential activity against a cultured Trypanosoma brucei brucei 427 strain. Several compounds displayed mostly modest in vitro anti-trypanosomal activity with compounds 10e and 10h emerging as active candidates with IC50 values of 4.09 and 5.11 µM, respectively. More importantly, a concomitant assessment of their activity against a human cervix adenocarcinoma (HeLa) cell line revealed that these compounds are non-toxic.
- Full Text:
- Date Issued: 2020
Comparative phototransformation of environmental pollutants using metallophthalocyanines supported on electrospun polymer fibers
- Zugle, Ruphino, Nyokong, Tebello
- Authors: Zugle, Ruphino , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/190509 , vital:45001 , xlink:href="https://doi.org/10.1002/app.38381"
- Description: The fluorescence and photoactivity of a series of Zn and Lu phthalocyanine complexes incorporated in various polymer fibers were investigated for the phototransformation of 4-chlorophenol, 4-nitrophenol, and methyl orange. The phthalocyanine complexes functionalized on polystyrene and polysulfone polymer fibers could be applied in the degradation of 4-chlorophenol, 4-nitrophenol, and methyl orange with 4-chlorophenol being much more susceptible to degradation while methyl orange was the least. Also polymer fibers of polystyrene were found to be reusable.
- Full Text:
- Date Issued: 2013
- Authors: Zugle, Ruphino , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/190509 , vital:45001 , xlink:href="https://doi.org/10.1002/app.38381"
- Description: The fluorescence and photoactivity of a series of Zn and Lu phthalocyanine complexes incorporated in various polymer fibers were investigated for the phototransformation of 4-chlorophenol, 4-nitrophenol, and methyl orange. The phthalocyanine complexes functionalized on polystyrene and polysulfone polymer fibers could be applied in the degradation of 4-chlorophenol, 4-nitrophenol, and methyl orange with 4-chlorophenol being much more susceptible to degradation while methyl orange was the least. Also polymer fibers of polystyrene were found to be reusable.
- Full Text:
- Date Issued: 2013
Zinc (II) 2, 9, 16, 23-tetrakis [4-(N-methylpyridyloxy)]-phthalocyanine anchored on an electrospun polysulfone polymer fiber: Application for photosensitized conversion of methyl orange
- Zugle, Ruphino, Nyokong, Tebello
- Authors: Zugle, Ruphino , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/232741 , vital:50020 , xlink:href="https://doi.org/10.1016/j.molcata.2012.10.001"
- Description: In this work, a comparative study of photodegradation of methyl orange, an azo dye, in homogeneous aqueous solution of a quarternized cationic zinc phthalocyanine and a heterogeneous catalytic system based on the same phthalocyanine anchored on polysulfone polymer fiber is presented. In both cases, conversion involved the azo bond of the dye with no detectable opening up of the aromatic benzene rings. The reaction kinetics in both cases were consistent with first order with the conversion occurring in the homogeneous system being faster than when the functionalized polymer fiber was used. The reaction products consisted of a coupling product as well as a series of oligopolymeric products.
- Full Text:
- Date Issued: 2013
- Authors: Zugle, Ruphino , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/232741 , vital:50020 , xlink:href="https://doi.org/10.1016/j.molcata.2012.10.001"
- Description: In this work, a comparative study of photodegradation of methyl orange, an azo dye, in homogeneous aqueous solution of a quarternized cationic zinc phthalocyanine and a heterogeneous catalytic system based on the same phthalocyanine anchored on polysulfone polymer fiber is presented. In both cases, conversion involved the azo bond of the dye with no detectable opening up of the aromatic benzene rings. The reaction kinetics in both cases were consistent with first order with the conversion occurring in the homogeneous system being faster than when the functionalized polymer fiber was used. The reaction products consisted of a coupling product as well as a series of oligopolymeric products.
- Full Text:
- Date Issued: 2013
Electrospun polyacrylic acid polymer fibers functionalized with metallophthalocyanines for photosensitizing and gas sensing applications
- Zugle, Ruphino, Nyokong, Tebello
- Authors: Zugle, Ruphino , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/243543 , vital:51162 , xlink:href="https://doi.org/10.1080/10601325.2012.662006"
- Description: The photophysical and photochemical properties of tetraaminophthalocyanine complexes of lutetium and zinc covalently linked to polyacrylic acid were studied alongside those of unsubstituted zinc phthalocyanine within the same polymeric fiber matrix. All three phthalocyanines within the solid fiber matrices showed photoactivity by the generation of singlet oxygen as was observed in solution. The fluorescence behaviors of the composite fibers equally parallel those in solution. For the unsubstituted zinc phthalocyanine composite, the fiber showed fluorescence quenching on interaction with gaseous nitrogen dioxide similar to that in DMF and, thus could be a promising nanofabric material in developing optoelectronic devices that are responsive to the gas.
- Full Text:
- Date Issued: 2012
- Authors: Zugle, Ruphino , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/243543 , vital:51162 , xlink:href="https://doi.org/10.1080/10601325.2012.662006"
- Description: The photophysical and photochemical properties of tetraaminophthalocyanine complexes of lutetium and zinc covalently linked to polyacrylic acid were studied alongside those of unsubstituted zinc phthalocyanine within the same polymeric fiber matrix. All three phthalocyanines within the solid fiber matrices showed photoactivity by the generation of singlet oxygen as was observed in solution. The fluorescence behaviors of the composite fibers equally parallel those in solution. For the unsubstituted zinc phthalocyanine composite, the fiber showed fluorescence quenching on interaction with gaseous nitrogen dioxide similar to that in DMF and, thus could be a promising nanofabric material in developing optoelectronic devices that are responsive to the gas.
- Full Text:
- Date Issued: 2012
Photophysical characterization of dysprosium, erbium and lutetium phthalocyanines tetrasubstituted with phenoxy groups at non-peripheral positions
- Zugle, Ruphino, Litwinski, Christian, Nyokong, Tebello
- Authors: Zugle, Ruphino , Litwinski, Christian , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/247561 , vital:51595 , xlink:href="https://doi.org/10.1016/j.poly.2011.03.030"
- Description: Dysprosium bis-phthalocyanine and monomeric phthalocyanines of erbium and lutetium with non-peripheral phenoxy substituents have been synthesized using two different preparative routes. Photophysical studies on these phthalocyanines revealed that the triplet states of dysprosium and erbium are not populated while the monomeric phthalocyanine complex of lutetium is populated with a quantum yield of 0.83 and a lifetime of 25 μs in DMSO. It was further found that the phthalocyanine complex of lutetium was capable of photochemical generation of singlet state molecular oxygen with yield of 0.71 in THF, thus a promising photosensitizer. However, the three phthalocyanine molecules have very low fluorescence quantum yields of less than 0.01.
- Full Text:
- Date Issued: 2011
- Authors: Zugle, Ruphino , Litwinski, Christian , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/247561 , vital:51595 , xlink:href="https://doi.org/10.1016/j.poly.2011.03.030"
- Description: Dysprosium bis-phthalocyanine and monomeric phthalocyanines of erbium and lutetium with non-peripheral phenoxy substituents have been synthesized using two different preparative routes. Photophysical studies on these phthalocyanines revealed that the triplet states of dysprosium and erbium are not populated while the monomeric phthalocyanine complex of lutetium is populated with a quantum yield of 0.83 and a lifetime of 25 μs in DMSO. It was further found that the phthalocyanine complex of lutetium was capable of photochemical generation of singlet state molecular oxygen with yield of 0.71 in THF, thus a promising photosensitizer. However, the three phthalocyanine molecules have very low fluorescence quantum yields of less than 0.01.
- Full Text:
- Date Issued: 2011
Physico-chemical properties of lutetium phthalocyanine complexes in solution and in solid polystyrene polymer fibers and their application in photoconversion of 4-nitrophenol
- Zugle, Ruphino, Nyokong, Tebello
- Authors: Zugle, Ruphino , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/243520 , vital:51160 , xlink:href="https://doi.org/10.1016/j.molcata.2012.02.010"
- Description: The photophysical and photochemical behavior of two phthalocyanine complexes of lutetium peripherally substituted with tetraphenoxy and tetra-2-pyridiloxy groups were studied in solution and when dispersed in polystyrene polymer fiber. The phthalocyanines were found not to fluoresce significantly in solution and not at all within the fiber matrix as compared with standard unsubstituted zinc phthalocyanine. They showed very promising photoactivity in solution with high singlet oxygen quantum yields. Their photoactivity within the polymer fiber matrix was also demonstrated with the photoconversion of 4-nitrophenol, a water pollutant. The photodegradation process with both phthalocyanines follows first order kinetics similar to that observed for the zinc phthalocyanine and the photo-products were found to be hydroquinone, benzoquinone and 4-nitrocatechol.
- Full Text:
- Date Issued: 2012
- Authors: Zugle, Ruphino , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/243520 , vital:51160 , xlink:href="https://doi.org/10.1016/j.molcata.2012.02.010"
- Description: The photophysical and photochemical behavior of two phthalocyanine complexes of lutetium peripherally substituted with tetraphenoxy and tetra-2-pyridiloxy groups were studied in solution and when dispersed in polystyrene polymer fiber. The phthalocyanines were found not to fluoresce significantly in solution and not at all within the fiber matrix as compared with standard unsubstituted zinc phthalocyanine. They showed very promising photoactivity in solution with high singlet oxygen quantum yields. Their photoactivity within the polymer fiber matrix was also demonstrated with the photoconversion of 4-nitrophenol, a water pollutant. The photodegradation process with both phthalocyanines follows first order kinetics similar to that observed for the zinc phthalocyanine and the photo-products were found to be hydroquinone, benzoquinone and 4-nitrocatechol.
- Full Text:
- Date Issued: 2012
Photooxidation of 4-chlorophenol sensitized by lutetium tetraphenoxy phthalocyanine anchored on electrospun polystyrene polymer fiber
- Zugle, Ruphino, Antunes, Edith M, Khene, Samson M, Nyokong, Tebello
- Authors: Zugle, Ruphino , Antunes, Edith M , Khene, Samson M , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/245787 , vital:51405 , xlink:href="https://doi.org/10.1016/j.poly.2011.11.005"
- Description: An electrospun polystyrene (PS) fiber incorporating tetraphenoxy phthalocyanine complex of lutetium (LuTPPc/PS) as a photosensitizer was applied for the degradation of 4-chlorophenol in aqueous solution in the presence of visible light. The photocatalytic activity of the LuTPPc in the fiber was compared to that of zinc phthalocyanine (ZnPc) incorporated into the PS fiber, and the former showed higher activity. UV–Vis spectral changes of sample solutions indicated transformation of the analyte with first order kinetics and half-lives that are within one and half hours for LuTPPc/PS. Products identified from the spectral changes and gas chromatography were benzoquinone, hydroquinone and 4,4′-dihydroxydiphenol suggesting that the photodegradation of 4-chlorophenol was through both Types I and II mechanisms.
- Full Text:
- Date Issued: 2012
- Authors: Zugle, Ruphino , Antunes, Edith M , Khene, Samson M , Nyokong, Tebello
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/245787 , vital:51405 , xlink:href="https://doi.org/10.1016/j.poly.2011.11.005"
- Description: An electrospun polystyrene (PS) fiber incorporating tetraphenoxy phthalocyanine complex of lutetium (LuTPPc/PS) as a photosensitizer was applied for the degradation of 4-chlorophenol in aqueous solution in the presence of visible light. The photocatalytic activity of the LuTPPc in the fiber was compared to that of zinc phthalocyanine (ZnPc) incorporated into the PS fiber, and the former showed higher activity. UV–Vis spectral changes of sample solutions indicated transformation of the analyte with first order kinetics and half-lives that are within one and half hours for LuTPPc/PS. Products identified from the spectral changes and gas chromatography were benzoquinone, hydroquinone and 4,4′-dihydroxydiphenol suggesting that the photodegradation of 4-chlorophenol was through both Types I and II mechanisms.
- Full Text:
- Date Issued: 2012
Photophysical and photochemical behavior of electrospun fibers of a polyurethane polymer chemically linked to lutetium carboxyphenoxy phthalocyanine
- Zugle, Ruphino, Litwinski, Christian, Torto, Nelson, Nyokong, Tebello
- Authors: Zugle, Ruphino , Litwinski, Christian , Torto, Nelson , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/248428 , vital:51685 , xlink:href="https://doi.org/10.1039/C1NJ20126C"
- Description: A phthalocyanine complex of lutetium substituted with four peripherally substituted 4-carboxyphenoxy groups was synthesized using cyclotetramerisation reaction. Its structure was elucidated using conventional spectroscopic methods and elemental analysis. The spectral behavior of the complex was studied in DMF solution and in a solid polyurethane fiber matrix. The UV-Visible spectrum showed a red shift in its Q-band maximum absorption within the fiber as compared to that in solution. The triplet quantum yield in DMF was determined to be 0.51 with a lifetime of 2.7 μs and a singlet oxygen quantum yield of 0.33 with a lifetime of 19.85 μs in the same solvent. The functionalized phthalocyanine fiber could be a promising fabric material for applications such as self-disinfecting in wound dressing. A method based on the conversion of ADMA was used to estimate the singlet oxygen quantum yield of the Pc in the hybrid fiber. An estimated singlet oxygen quantum yield value of 0.11 in aqueous medium was obtained. The fluorescence quantum yield of the Pc was found to be 0.01 with a lifetime of 3.20 ns in DMF.
- Full Text:
- Date Issued: 2011
- Authors: Zugle, Ruphino , Litwinski, Christian , Torto, Nelson , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/248428 , vital:51685 , xlink:href="https://doi.org/10.1039/C1NJ20126C"
- Description: A phthalocyanine complex of lutetium substituted with four peripherally substituted 4-carboxyphenoxy groups was synthesized using cyclotetramerisation reaction. Its structure was elucidated using conventional spectroscopic methods and elemental analysis. The spectral behavior of the complex was studied in DMF solution and in a solid polyurethane fiber matrix. The UV-Visible spectrum showed a red shift in its Q-band maximum absorption within the fiber as compared to that in solution. The triplet quantum yield in DMF was determined to be 0.51 with a lifetime of 2.7 μs and a singlet oxygen quantum yield of 0.33 with a lifetime of 19.85 μs in the same solvent. The functionalized phthalocyanine fiber could be a promising fabric material for applications such as self-disinfecting in wound dressing. A method based on the conversion of ADMA was used to estimate the singlet oxygen quantum yield of the Pc in the hybrid fiber. An estimated singlet oxygen quantum yield value of 0.11 in aqueous medium was obtained. The fluorescence quantum yield of the Pc was found to be 0.01 with a lifetime of 3.20 ns in DMF.
- Full Text:
- Date Issued: 2011
The stories African lawyers could tell when analysing legal issues: Lessons for social sciences teachers
- Authors: Zongwe, Dunia P
- Date: 2021
- Subjects: Decolonization Storytelling Law--Study and teaching Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6989 , vital:52634 , xlink:href="https://doi.org/10.4102/hts.v77i2.6828"
- Description: Activists and academics have clamoured for the decolonisation of knowledge, including law. But, unfortunately hardly anyone has put forth strategies for how faculties should decolonise the law. A number of jurists have underscored the necessity to draw on customary laws and traditional values. Still, the #RhodesMustFall movement has, for the most part, been loud on the outcomes, but quiet on the methodologies. Joining the conversation on the decolonisation of epistemologies, this article contributes to the ongoing efforts to sanitise the law by proposing to revive African oral storytelling cultures as a way to analyse the questions of law facing society. To live up to this task, this article adopts decolonial theory and, through stylised examples, illustrates how lawyers and social scientists in Africa can utilise storytelling to contextualise, (de)construct, and comprehend those questions. This article assumes that lawyers can use African storytelling alongside the prevailing doctrinal method. That method, relaying the coloniality of law and captured by the acronym IRAC (issue(s), rules, application, and conclusion), trains students to approach conflict in society through a highly abstract and decontextualised problem-solving model. Lately, some (Western) social scientists have (re)discovered the practicality of storytelling in presenting analysis and research. However, in African oral traditions, stories worked differently from the manner in which those scientists employ them. African storytelling played a leading role, not only in conveying collective wisdom and social memory from one generation to the next, but also as a medium through which communities transmit the values that hold them together. Contribution: This article adds to the scholarship on storytelling and narratology by showing how educators can utilise stories to analyse legal questions. That rich scholarship in the humanities and the social sciences has so far not taken seriously the possibility of using stories to analyse research problems. Instead, scholars focus on storytelling mainly as a way of presenting science, not as an analytical tool. This article bridges that gap and demonstrates the analytical value of storytelling. Keywords: decolonisation of knowledge; decolonial theory; storytelling; Africa; analysis; epistemology; legal education; oral tradition.
- Full Text:
- Date Issued: 2021
- Authors: Zongwe, Dunia P
- Date: 2021
- Subjects: Decolonization Storytelling Law--Study and teaching Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6989 , vital:52634 , xlink:href="https://doi.org/10.4102/hts.v77i2.6828"
- Description: Activists and academics have clamoured for the decolonisation of knowledge, including law. But, unfortunately hardly anyone has put forth strategies for how faculties should decolonise the law. A number of jurists have underscored the necessity to draw on customary laws and traditional values. Still, the #RhodesMustFall movement has, for the most part, been loud on the outcomes, but quiet on the methodologies. Joining the conversation on the decolonisation of epistemologies, this article contributes to the ongoing efforts to sanitise the law by proposing to revive African oral storytelling cultures as a way to analyse the questions of law facing society. To live up to this task, this article adopts decolonial theory and, through stylised examples, illustrates how lawyers and social scientists in Africa can utilise storytelling to contextualise, (de)construct, and comprehend those questions. This article assumes that lawyers can use African storytelling alongside the prevailing doctrinal method. That method, relaying the coloniality of law and captured by the acronym IRAC (issue(s), rules, application, and conclusion), trains students to approach conflict in society through a highly abstract and decontextualised problem-solving model. Lately, some (Western) social scientists have (re)discovered the practicality of storytelling in presenting analysis and research. However, in African oral traditions, stories worked differently from the manner in which those scientists employ them. African storytelling played a leading role, not only in conveying collective wisdom and social memory from one generation to the next, but also as a medium through which communities transmit the values that hold them together. Contribution: This article adds to the scholarship on storytelling and narratology by showing how educators can utilise stories to analyse legal questions. That rich scholarship in the humanities and the social sciences has so far not taken seriously the possibility of using stories to analyse research problems. Instead, scholars focus on storytelling mainly as a way of presenting science, not as an analytical tool. This article bridges that gap and demonstrates the analytical value of storytelling. Keywords: decolonisation of knowledge; decolonial theory; storytelling; Africa; analysis; epistemology; legal education; oral tradition.
- Full Text:
- Date Issued: 2021
Nobody can really afford legal services: the price of justice in Namibia
- Authors: Zongwe, Dunia P
- Date: 2021
- Subjects: Legal assistance to the poor , Namibia
- Language: English
- Type: article
- Identifier: http://hdl.handle.net/11260/5375 , vital:44543 , https://perjournal.co.za/article/view/6420
- Description: Nobody (except for the privileged few) can afford legal services in Namibia. In the light of this dawning awareness, how should the government and other stakeholders design the legal profession so that the greatest number of Namibians can access legal services and, ultimately, justice while preserving the profession's financial viability? The predominantly economic nature of this question means that its solutions lie less in the field of law than in the field of economics. Thus, this article adopts a methodology that reflects that insight.As a primary purpose, this article works towards solving the high cost of legal services in Namibia. It utilises a literature-review methodology that searches the scholarship on the legal profession for practical, down-to-earth solutions put forward in other countries to take the edge off the prohibitive cost of legal services. The article mainly finds that, if structured as a compulsory salary deduction, legal insurance promises the greatest positive impact on costs. And it concludes that the optimal solutions should consist of measures aimed at heightening competition in the legal profession and measures that broaden cost-sharing in providing legal assistance to the public. The article argues that competition can be effectively increased by lubricating the flow of information about prices and services, and by having more public entities bear the burden of expanding the system of legal assistance.
- Full Text:
- Date Issued: 2021
- Authors: Zongwe, Dunia P
- Date: 2021
- Subjects: Legal assistance to the poor , Namibia
- Language: English
- Type: article
- Identifier: http://hdl.handle.net/11260/5375 , vital:44543 , https://perjournal.co.za/article/view/6420
- Description: Nobody (except for the privileged few) can afford legal services in Namibia. In the light of this dawning awareness, how should the government and other stakeholders design the legal profession so that the greatest number of Namibians can access legal services and, ultimately, justice while preserving the profession's financial viability? The predominantly economic nature of this question means that its solutions lie less in the field of law than in the field of economics. Thus, this article adopts a methodology that reflects that insight.As a primary purpose, this article works towards solving the high cost of legal services in Namibia. It utilises a literature-review methodology that searches the scholarship on the legal profession for practical, down-to-earth solutions put forward in other countries to take the edge off the prohibitive cost of legal services. The article mainly finds that, if structured as a compulsory salary deduction, legal insurance promises the greatest positive impact on costs. And it concludes that the optimal solutions should consist of measures aimed at heightening competition in the legal profession and measures that broaden cost-sharing in providing legal assistance to the public. The article argues that competition can be effectively increased by lubricating the flow of information about prices and services, and by having more public entities bear the burden of expanding the system of legal assistance.
- Full Text:
- Date Issued: 2021
The stories African lawyers could tell when analysing legal issues: Lessons for social sciences teachers
- Authors: Zongwe, Dunia P
- Date: 2021
- Subjects: Decolonization Storytelling Law--Study and teaching Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/7215 , vital:53086 , xlink:href="https://doi.org/10.4102/hts.v77i2.6828"
- Description: Activists and academics have clamoured for the decolonisation of knowledge, including law. But, unfortunately hardly anyone has put forth strategies for how faculties should decolonise the law. A number of jurists have underscored the necessity to draw on customary laws and traditional values. Still, the #RhodesMustFall movement has, for the most part, been loud on the outcomes, but quiet on the methodologies. Joining the conversation on the decolonisation of epistemologies, this article contributes to the ongoing efforts to sanitise the law by proposing to revive African oral storytelling cultures as a way to analyse the questions of law facing society. To live up to this task, this article adopts decolonial theory and, through stylised examples, illustrates how lawyers and social scientists in Africa can utilise storytelling to contextualise, (de)construct, and comprehend those questions. This article assumes that lawyers can use African storytelling alongside the prevailing doctrinal method. That method, relaying the coloniality of law and captured by the acronym IRAC (issue(s), rules, application, and conclusion), trains students to approach conflict in society through a highly abstract and decontextualised problem-solving model. Lately, some (Western) social scientists have (re)discovered the practicality of storytelling in presenting analysis and research. However, in African oral traditions, stories worked differently from the manner in which those scientists employ them. African storytelling played a leading role, not only in conveying collective wisdom and social memory from one generation to the next, but also as a medium through which communities transmit the values that hold them together. Contribution: This article adds to the scholarship on storytelling and narratology by showing how educators can utilise stories to analyse legal questions. That rich scholarship in the humanities and the social sciences has so far not taken seriously the possibility of using stories to analyse research problems. Instead, scholars focus on storytelling mainly as a way of presenting science, not as an analytical tool. This article bridges that gap and demonstrates the analytical value of storytelling. Keywords: decolonisation of knowledge; decolonial theory; storytelling; Africa; analysis; epistemology; legal education; oral tradition.
- Full Text:
- Date Issued: 2021
- Authors: Zongwe, Dunia P
- Date: 2021
- Subjects: Decolonization Storytelling Law--Study and teaching Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/7215 , vital:53086 , xlink:href="https://doi.org/10.4102/hts.v77i2.6828"
- Description: Activists and academics have clamoured for the decolonisation of knowledge, including law. But, unfortunately hardly anyone has put forth strategies for how faculties should decolonise the law. A number of jurists have underscored the necessity to draw on customary laws and traditional values. Still, the #RhodesMustFall movement has, for the most part, been loud on the outcomes, but quiet on the methodologies. Joining the conversation on the decolonisation of epistemologies, this article contributes to the ongoing efforts to sanitise the law by proposing to revive African oral storytelling cultures as a way to analyse the questions of law facing society. To live up to this task, this article adopts decolonial theory and, through stylised examples, illustrates how lawyers and social scientists in Africa can utilise storytelling to contextualise, (de)construct, and comprehend those questions. This article assumes that lawyers can use African storytelling alongside the prevailing doctrinal method. That method, relaying the coloniality of law and captured by the acronym IRAC (issue(s), rules, application, and conclusion), trains students to approach conflict in society through a highly abstract and decontextualised problem-solving model. Lately, some (Western) social scientists have (re)discovered the practicality of storytelling in presenting analysis and research. However, in African oral traditions, stories worked differently from the manner in which those scientists employ them. African storytelling played a leading role, not only in conveying collective wisdom and social memory from one generation to the next, but also as a medium through which communities transmit the values that hold them together. Contribution: This article adds to the scholarship on storytelling and narratology by showing how educators can utilise stories to analyse legal questions. That rich scholarship in the humanities and the social sciences has so far not taken seriously the possibility of using stories to analyse research problems. Instead, scholars focus on storytelling mainly as a way of presenting science, not as an analytical tool. This article bridges that gap and demonstrates the analytical value of storytelling. Keywords: decolonisation of knowledge; decolonial theory; storytelling; Africa; analysis; epistemology; legal education; oral tradition.
- Full Text:
- Date Issued: 2021
The stories African lawyers could tell when analysing legal issues: Lessons for social sciences teachers
- Authors: Zongwe, Dunia P
- Date: 2021
- Subjects: Africa storytelling
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6229 , vital:45341 , https://doi.org/10.4102/hts.v77i2.6828
- Description: Activists and academics have clamoured for the decolonisation of knowledge, including law. But, unfortunately hardly anyone has put forth strategies for how faculties should decolonise the law. A number of jurists have underscored the necessity to draw on customary laws and traditional values. Still, the #RhodesMustFall movement has, for the most part, been loud on the outcomes, but quiet on the methodologies. Joining the conversation on the decolonisation of epistemologies, this article contributes to the ongoing efforts to sanitise the law by proposing to revive African oral storytelling cultures as a way to analyse the questions of law facing society. To live up to this task, this article adopts decolonial theory and, through stylised examples, illustrates how lawyers and social scientists in Africa can utilise storytelling to contextualise, (de)construct, and comprehend those questions. This article assumes that lawyers can use African storytelling alongside the prevailing doctrinal method. That method, relaying the coloniality of law and captured by the acronym IRAC (issue(s), rules, application, and conclusion), trains students to approach conflict in society through a highly abstract and decontextualised problem-solving model. Lately, some (Western) social scientists have (re)discovered the practicality of storytelling in presenting analysis and research. However, in African oral traditions, stories worked differently from the manner in which those scientists employ them. African storytelling played a leading role, not only in conveying collective wisdom and social memory from one generation to the next, but also as a medium through which communities transmit the values that hold them together. Contribution: This article adds to the scholarship on storytelling and narratology by showing how educators can utilise stories to analyse legal questions. That rich scholarship in the humanities and the social sciences has so far not taken seriously the possibility of using stories to analyse research problems. Instead, scholars focus on storytelling mainly as a way of presenting science, not as an analytical tool. This article bridges that gap and demonstrates the analytical value of storytelling.
- Full Text:
- Date Issued: 2021
- Authors: Zongwe, Dunia P
- Date: 2021
- Subjects: Africa storytelling
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6229 , vital:45341 , https://doi.org/10.4102/hts.v77i2.6828
- Description: Activists and academics have clamoured for the decolonisation of knowledge, including law. But, unfortunately hardly anyone has put forth strategies for how faculties should decolonise the law. A number of jurists have underscored the necessity to draw on customary laws and traditional values. Still, the #RhodesMustFall movement has, for the most part, been loud on the outcomes, but quiet on the methodologies. Joining the conversation on the decolonisation of epistemologies, this article contributes to the ongoing efforts to sanitise the law by proposing to revive African oral storytelling cultures as a way to analyse the questions of law facing society. To live up to this task, this article adopts decolonial theory and, through stylised examples, illustrates how lawyers and social scientists in Africa can utilise storytelling to contextualise, (de)construct, and comprehend those questions. This article assumes that lawyers can use African storytelling alongside the prevailing doctrinal method. That method, relaying the coloniality of law and captured by the acronym IRAC (issue(s), rules, application, and conclusion), trains students to approach conflict in society through a highly abstract and decontextualised problem-solving model. Lately, some (Western) social scientists have (re)discovered the practicality of storytelling in presenting analysis and research. However, in African oral traditions, stories worked differently from the manner in which those scientists employ them. African storytelling played a leading role, not only in conveying collective wisdom and social memory from one generation to the next, but also as a medium through which communities transmit the values that hold them together. Contribution: This article adds to the scholarship on storytelling and narratology by showing how educators can utilise stories to analyse legal questions. That rich scholarship in the humanities and the social sciences has so far not taken seriously the possibility of using stories to analyse research problems. Instead, scholars focus on storytelling mainly as a way of presenting science, not as an analytical tool. This article bridges that gap and demonstrates the analytical value of storytelling.
- Full Text:
- Date Issued: 2021
T Kondo (Ed) law and investment in Africa: the fovernance of foreign direct investment in Zimbabwe
- Authors: Zongwe, Dunia P
- Date: 2021
- Subjects: Investments, Foreign -- Africa, Sub-Saharan , Zimbabwe -- Economic conditions , Corporate governance
- Language: English
- Type: text , review , article
- Identifier: http://hdl.handle.net/11260/6387 , vital:45443 , xlink:href="http://dx.doi.org/10.17159/2077-4907/2021/ldd.v25.16 "
- Description: Tinashe Kondo’s book, Law and investment in Africa, narrates the efforts of a country to regain the trust [and the love] of foreign investors after several decades of argument and hostility. Encapsulated in the “Zimbabwe is open for business” slogan, these efforts show “how a country can move to regain credibility and commit to global rules despite its recent history”. This review of Kondo’s book concerns the manner in which readers can take advantage of this immensely useful publication. Particularly, this review looks into the book in order to advise law academics on possible strategies to integrate the book into their curricula in Zimbabwe and elsewhere on the continent.
- Full Text:
- Date Issued: 2021
- Authors: Zongwe, Dunia P
- Date: 2021
- Subjects: Investments, Foreign -- Africa, Sub-Saharan , Zimbabwe -- Economic conditions , Corporate governance
- Language: English
- Type: text , review , article
- Identifier: http://hdl.handle.net/11260/6387 , vital:45443 , xlink:href="http://dx.doi.org/10.17159/2077-4907/2021/ldd.v25.16 "
- Description: Tinashe Kondo’s book, Law and investment in Africa, narrates the efforts of a country to regain the trust [and the love] of foreign investors after several decades of argument and hostility. Encapsulated in the “Zimbabwe is open for business” slogan, these efforts show “how a country can move to regain credibility and commit to global rules despite its recent history”. This review of Kondo’s book concerns the manner in which readers can take advantage of this immensely useful publication. Particularly, this review looks into the book in order to advise law academics on possible strategies to integrate the book into their curricula in Zimbabwe and elsewhere on the continent.
- Full Text:
- Date Issued: 2021
A Feasibility Study on the Efficacy of Functional Near-Infrared Spectrometry (fNIRS) to Measure Prefrontal Activation in Paediatric HIV
- Zondo, Sizwe, Ferreira-Correia, Aline, Cockcroft, Kate
- Authors: Zondo, Sizwe , Ferreira-Correia, Aline , Cockcroft, Kate
- Date: 2024
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/450556 , vital:74960 , xlink:href="https://www.hindawi.com/journals/js/2024/4970794/"
- Description: Human immunodeficiency virus (HIV) infection is associated with disturbed neurotransmission and aberrant cortical networks. Although advances in the imaging of brain microarchitecture following neuroHIV has added to our knowledge of structural and functional changes associated with HIV, no data exists on paediatric HIV using optical neuroimaging techniques. This study investigated the feasibility of optical neuroimaging in paediatric HIV using functional near-infrared spectrometry (fNIRS). We measured prefrontal brain activation while participants executed a sustained attention task. We specifically tested whether patients living with HIV and study controls could perform the study protocol and whether we could measure the typical fNIRS haemodynamic response associated with neuronal activity. Eighteen participants (10 HIV participants, mean age: 13.9, SD = 1.66 years; 8 controls, mean age: 14.8, SD = 1.28 years), matched for sex, grade, and socio-economic status, were included in the study. All participants completed the Stroop colour word test (SCWT). Oxygenated haemoglobin concentration and the deoxygenated haemoglobin signal were recorded from the dorsolateral prefrontal cortex and the frontopolar area (FA) using fNIRS. The control group performed significantly better in terms of reaction time on the congruent and incongruent condition (congruent: t (16) = −3.36, : incongruent: ). A pooled group analysis of the sample indicated significant activation in the DLPF and FA to the congruent condition of the SCWT (). Although cortical activation was noted in the DLPF and the FA in each of the groups when analysed independently, this neural activation did not reach statistical significance. The results show promise that fNIRS techniques are feasible for assessing prefrontal cortical activity in paediatric HIV. Future studies should seek to reduce the signal-to-noise ratio and consider inter-individual variability when measuring prefrontal activation in paediatric samples.
- Full Text:
- Date Issued: 2024
- Authors: Zondo, Sizwe , Ferreira-Correia, Aline , Cockcroft, Kate
- Date: 2024
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/450556 , vital:74960 , xlink:href="https://www.hindawi.com/journals/js/2024/4970794/"
- Description: Human immunodeficiency virus (HIV) infection is associated with disturbed neurotransmission and aberrant cortical networks. Although advances in the imaging of brain microarchitecture following neuroHIV has added to our knowledge of structural and functional changes associated with HIV, no data exists on paediatric HIV using optical neuroimaging techniques. This study investigated the feasibility of optical neuroimaging in paediatric HIV using functional near-infrared spectrometry (fNIRS). We measured prefrontal brain activation while participants executed a sustained attention task. We specifically tested whether patients living with HIV and study controls could perform the study protocol and whether we could measure the typical fNIRS haemodynamic response associated with neuronal activity. Eighteen participants (10 HIV participants, mean age: 13.9, SD = 1.66 years; 8 controls, mean age: 14.8, SD = 1.28 years), matched for sex, grade, and socio-economic status, were included in the study. All participants completed the Stroop colour word test (SCWT). Oxygenated haemoglobin concentration and the deoxygenated haemoglobin signal were recorded from the dorsolateral prefrontal cortex and the frontopolar area (FA) using fNIRS. The control group performed significantly better in terms of reaction time on the congruent and incongruent condition (congruent: t (16) = −3.36, : incongruent: ). A pooled group analysis of the sample indicated significant activation in the DLPF and FA to the congruent condition of the SCWT (). Although cortical activation was noted in the DLPF and the FA in each of the groups when analysed independently, this neural activation did not reach statistical significance. The results show promise that fNIRS techniques are feasible for assessing prefrontal cortical activity in paediatric HIV. Future studies should seek to reduce the signal-to-noise ratio and consider inter-individual variability when measuring prefrontal activation in paediatric samples.
- Full Text:
- Date Issued: 2024
The cognitive remediation of attention in HIV-associated neurocognitive disorders (HAND): A meta-analysis and systematic review
- Authors: Zondo, Sizwe
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/450732 , vital:74977 , xlink:href="https://doi.org/10.12688/f1000research.132166.1"
- Description: Despite medical advances in Highly Active Antiretroviral Therapy (HAART), patients living with HIV continue to be at risk for developing HIV-associated neurocognitive disorders (HAND). The optimization of non-HAART interventions, including cognitive rehabilitation therapy (CRT), shows promise in reversing the impact of HAND. No data exist indicating the efficacy of CRT in remediating attention skills following neuroHIV. This paper presents a meta-analysis of randomised and non-randomised controlled trials (RCTs) to remediate attention skills following HIV CRT.
- Full Text:
- Date Issued: 2023
- Authors: Zondo, Sizwe
- Date: 2023
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/450732 , vital:74977 , xlink:href="https://doi.org/10.12688/f1000research.132166.1"
- Description: Despite medical advances in Highly Active Antiretroviral Therapy (HAART), patients living with HIV continue to be at risk for developing HIV-associated neurocognitive disorders (HAND). The optimization of non-HAART interventions, including cognitive rehabilitation therapy (CRT), shows promise in reversing the impact of HAND. No data exist indicating the efficacy of CRT in remediating attention skills following neuroHIV. This paper presents a meta-analysis of randomised and non-randomised controlled trials (RCTs) to remediate attention skills following HIV CRT.
- Full Text:
- Date Issued: 2023
Plasmodium falciparum Hsp70-z, an Hsp110 homologue, exhibits independent chaperone activity and interacts with Hsp70-1 in a nucleotide-dependent fashion
- Ziningwa, Tawanda, Achilonu, Ikechukwu, Hoppe, Heinrich C, Prinsloo, Earl, Dirr, Heinrich W, Shonhai, Addmore
- Authors: Ziningwa, Tawanda , Achilonu, Ikechukwu , Hoppe, Heinrich C , Prinsloo, Earl , Dirr, Heinrich W , Shonhai, Addmore
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431765 , vital:72802 , xlink:href="https://doi.org/10.1007/s12192-016-0678-4"
- Description: The role of molecular chaperones, among them heat shock proteins (Hsps), in the development of malaria parasites has been well documented. Hsp70s are molecular chaperones that facilitate protein folding. Hsp70 proteins are composed of an N-terminal nucleotide binding domain (NBD), which confers them with ATPase activity and a Cterminal substrate binding domain (SBD). In the ADPbound state, Hsp70 possesses high affinity for substrate and releases the folded substrate when it is bound to ATP. The two domains are connected by a conserved linker segment. Hsp110 proteins possess an extended lid segment, a feature that distinguishes them from canonical Hsp70s.
- Full Text:
- Date Issued: 2016
- Authors: Ziningwa, Tawanda , Achilonu, Ikechukwu , Hoppe, Heinrich C , Prinsloo, Earl , Dirr, Heinrich W , Shonhai, Addmore
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431765 , vital:72802 , xlink:href="https://doi.org/10.1007/s12192-016-0678-4"
- Description: The role of molecular chaperones, among them heat shock proteins (Hsps), in the development of malaria parasites has been well documented. Hsp70s are molecular chaperones that facilitate protein folding. Hsp70 proteins are composed of an N-terminal nucleotide binding domain (NBD), which confers them with ATPase activity and a Cterminal substrate binding domain (SBD). In the ADPbound state, Hsp70 possesses high affinity for substrate and releases the folded substrate when it is bound to ATP. The two domains are connected by a conserved linker segment. Hsp110 proteins possess an extended lid segment, a feature that distinguishes them from canonical Hsp70s.
- Full Text:
- Date Issued: 2016
Plasmodium falciparum Hop (PfHop) interacts with the Hsp70 chaperone in a nucleotide-dependent fashion and exhibits ligand selectivity
- Zininga, Tawanda, Makumire, Stanley, Gitau, Grace W, Njunge, James M, Pooe, Ofentse J, Klimek, Hanna, Scheurr, Robina, Raifer, Hartmann, Prinsloo, Earl, Przyborski, Jude M, Hoppe, Heinrich C, Shonhai, Addmore
- Authors: Zininga, Tawanda , Makumire, Stanley , Gitau, Grace W , Njunge, James M , Pooe, Ofentse J , Klimek, Hanna , Scheurr, Robina , Raifer, Hartmann , Prinsloo, Earl , Przyborski, Jude M , Hoppe, Heinrich C , Shonhai, Addmore
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431752 , vital:72801 , xlink:href=" https://doi.org/10.1371/journal.pone.0135326"
- Description: Heat shock proteins (Hsps) play an important role in the development and pathogenicity of malaria parasites. One of the most prominent functions of Hsps is to facilitate the folding of other proteins. Hsps are thought to play a crucial role when malaria parasites invade their host cells and during their subsequent development in hepatocytes and red blood cells. It is thought that Hsps maintain proteostasis under the unfavourable conditions that malaria parasites encounter in the host environment. Although heat shock protein 70 (Hsp70) is capable of independent folding of some proteins, its functional cooperation with heat shock protein 90 (Hsp90) facilitates folding of some proteins such as kinases and steroid hormone receptors into their fully functional forms. The cooperation of Hsp70 and Hsp90 occurs through an adaptor protein called Hsp70-Hsp90 organising protein (Hop). We previously characterised the Hop protein from Plasmodium falciparum (PfHop). We observed that the protein co-localised with the cytosol-localised chaperones, PfHsp70-1 and PfHsp90 at the blood stages of the malaria parasite. In the current study, we demonstrated that PfHop is a stress-inducible protein. We further explored the direct interaction between PfHop and PfHsp70-1 using far Western and surface plasmon resonance (SPR) analyses.
- Full Text:
- Date Issued: 2015
- Authors: Zininga, Tawanda , Makumire, Stanley , Gitau, Grace W , Njunge, James M , Pooe, Ofentse J , Klimek, Hanna , Scheurr, Robina , Raifer, Hartmann , Prinsloo, Earl , Przyborski, Jude M , Hoppe, Heinrich C , Shonhai, Addmore
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431752 , vital:72801 , xlink:href=" https://doi.org/10.1371/journal.pone.0135326"
- Description: Heat shock proteins (Hsps) play an important role in the development and pathogenicity of malaria parasites. One of the most prominent functions of Hsps is to facilitate the folding of other proteins. Hsps are thought to play a crucial role when malaria parasites invade their host cells and during their subsequent development in hepatocytes and red blood cells. It is thought that Hsps maintain proteostasis under the unfavourable conditions that malaria parasites encounter in the host environment. Although heat shock protein 70 (Hsp70) is capable of independent folding of some proteins, its functional cooperation with heat shock protein 90 (Hsp90) facilitates folding of some proteins such as kinases and steroid hormone receptors into their fully functional forms. The cooperation of Hsp70 and Hsp90 occurs through an adaptor protein called Hsp70-Hsp90 organising protein (Hop). We previously characterised the Hop protein from Plasmodium falciparum (PfHop). We observed that the protein co-localised with the cytosol-localised chaperones, PfHsp70-1 and PfHsp90 at the blood stages of the malaria parasite. In the current study, we demonstrated that PfHop is a stress-inducible protein. We further explored the direct interaction between PfHop and PfHsp70-1 using far Western and surface plasmon resonance (SPR) analyses.
- Full Text:
- Date Issued: 2015
Overexpression, Purification and Characterisation of the Plasmodium falciparum Hsp70-z (PfHsp70-z) Protein
- Zininga, Tawanda, Achilonu, Ikechukwu, Hoppe, Heinrich C, Prinsloo, Earl, Dirr, Heinrich W, Shonhai, Addmore
- Authors: Zininga, Tawanda , Achilonu, Ikechukwu , Hoppe, Heinrich C , Prinsloo, Earl , Dirr, Heinrich W , Shonhai, Addmore
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431719 , vital:72799 , xlink:href="https://doi.org/10.1371/journal.pone.0129445"
- Description: Six Hsp70-like genes are represented on the genome of Plasmodium falciparum. Of these two occur in the cytosol: P. falciparum Hsp70-z (PfHsp70-z) and PfHsp70-1. PfHsp70-1 is a well characterised canonical Hsp70 that facilitates protein quality control and is crucial for the development of malaria parasites. There is very little known about PfHsp70-z. However, PfHsp70-z is known to be essential and is implicated in suppressing aggregation of asparagine-rich proteins of P. falciparum. In addition, its expression at the clinical stage of malaria correlates with disease prognosis. Based on structural evidence PfHsp70-z belongs to the Hsp110 family of proteins. Since Hsp110 proteins have been described as nucleotide exchange factors (NEFs) of their canonical Hsp70 counterparts, it has been speculated that PfHsp70-z may serve as a NEF of PfHsp70-1. In the current study, P. falciparum cells cultured in vitro were subjected to heat stress, triggering the enhanced expression of PfHsp70-z. Biochemical assays conducted using recombinant PfHsp70-z protein demonstrated that the protein is heat stable and possesses ATPase activity. Furthermore, we observed that PfHsp70-z is capable of self-association. The structural-functional features of PfHsp70-z provide further evidence for its role as a chaperone and possible nucleotide exchange factor of PfHsp70-1.
- Full Text:
- Date Issued: 2015
- Authors: Zininga, Tawanda , Achilonu, Ikechukwu , Hoppe, Heinrich C , Prinsloo, Earl , Dirr, Heinrich W , Shonhai, Addmore
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431719 , vital:72799 , xlink:href="https://doi.org/10.1371/journal.pone.0129445"
- Description: Six Hsp70-like genes are represented on the genome of Plasmodium falciparum. Of these two occur in the cytosol: P. falciparum Hsp70-z (PfHsp70-z) and PfHsp70-1. PfHsp70-1 is a well characterised canonical Hsp70 that facilitates protein quality control and is crucial for the development of malaria parasites. There is very little known about PfHsp70-z. However, PfHsp70-z is known to be essential and is implicated in suppressing aggregation of asparagine-rich proteins of P. falciparum. In addition, its expression at the clinical stage of malaria correlates with disease prognosis. Based on structural evidence PfHsp70-z belongs to the Hsp110 family of proteins. Since Hsp110 proteins have been described as nucleotide exchange factors (NEFs) of their canonical Hsp70 counterparts, it has been speculated that PfHsp70-z may serve as a NEF of PfHsp70-1. In the current study, P. falciparum cells cultured in vitro were subjected to heat stress, triggering the enhanced expression of PfHsp70-z. Biochemical assays conducted using recombinant PfHsp70-z protein demonstrated that the protein is heat stable and possesses ATPase activity. Furthermore, we observed that PfHsp70-z is capable of self-association. The structural-functional features of PfHsp70-z provide further evidence for its role as a chaperone and possible nucleotide exchange factor of PfHsp70-1.
- Full Text:
- Date Issued: 2015
Specialty Grand Challenges in Urban Agriculture: Ecological and Social Approaches to Sustainability Transformations
- Zimmerer, Karl S, Bell, Martha G, Chirisa, Innocent, Duvall, Chris S, Egerer, Monika, Hung, Po-Yi, Lerner, Amy M, Shackleton, Charlie M, Ward, James David, Yacamán Ochoa, Carolina
- Authors: Zimmerer, Karl S , Bell, Martha G , Chirisa, Innocent , Duvall, Chris S , Egerer, Monika , Hung, Po-Yi , Lerner, Amy M , Shackleton, Charlie M , Ward, James David , Yacamán Ochoa, Carolina
- Date: 2021
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/175779 , vital:42623 , https://doi.org/10.3389/fsufs.2021.668561
- Description: This synopsis of the Grand Challenges of Urban Agriculture (UA) is framed by the urgent need to understand and strengthen the expanding yet highly diverse roles of UA amid rapid global urbanization, failures of predominant food systems, and crises in systems of physical and mental health. More than half of humanity lives in cities today and by 2030 this is projected to grow to 60.4 percent, ~5 billion people (UN Habitat, 2020). More than 90 percent of urban demographic increase is anticipated to take place in the developing world.
- Full Text:
- Date Issued: 2021
- Authors: Zimmerer, Karl S , Bell, Martha G , Chirisa, Innocent , Duvall, Chris S , Egerer, Monika , Hung, Po-Yi , Lerner, Amy M , Shackleton, Charlie M , Ward, James David , Yacamán Ochoa, Carolina
- Date: 2021
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/175779 , vital:42623 , https://doi.org/10.3389/fsufs.2021.668561
- Description: This synopsis of the Grand Challenges of Urban Agriculture (UA) is framed by the urgent need to understand and strengthen the expanding yet highly diverse roles of UA amid rapid global urbanization, failures of predominant food systems, and crises in systems of physical and mental health. More than half of humanity lives in cities today and by 2030 this is projected to grow to 60.4 percent, ~5 billion people (UN Habitat, 2020). More than 90 percent of urban demographic increase is anticipated to take place in the developing world.
- Full Text:
- Date Issued: 2021