Synthesis and photophysicochemical properties of novel axially di-substituted silicon (IV) phthalocyanines and their photodynamic antimicrobial chemotherapy (PACT) activity against Staphylococcus aureus
- Authors: Sen, Pinar , Sindelo, Azole , Mafukidze, Donovan M , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186757 , vital:44531 , xlink:href="https://doi.org/10.1016/j.synthmet.2019.116203"
- Description: In this study, novel silicon (IV) phthalocyanine axially di-substituted with benzimidazole moieties (3) and its quaternized derivative (4) have been synthesized and fully characterized. The photophysical and photochemical properties of both phthalocyanines such as absorption, fluorescence and, singlet oxygen quantum yields, triplet state quantum yields and exited state lifetimes were investigated in solutions. These new silicon phthalocyanines exhibited low fluorescence but produced high singlet oxygen yields in both DMSO (compound 3 and 4) and aqueous media (compound 4). The quaternization of Si(IV)Pc (3) improved the triplet state quantum yield (ΦT) 0.61 to 0.83, consequently singlet oxygen generation (ΦΔ) increased to 0.69 from 0.42. Photodynamic antimicrobial chemotherapy activities (PACT) of Si(IV)Pc photosensitizers were determined towards Staphylococcus aureus. The higher efficiency was obtained with cationic derivative (4) giving reduction percentage value of 99.75%.
- Full Text:
- Date Issued: 2019
Synthesis and properties of chiral amide-bonded porphyrin dimers with various functional bridging blocks
- Authors: Zhu, Weihua , Haider, Syed Najeeb-uz-Zaman , Zhang, Honglin , Attatsi, Isaac K , Mack, John , Dingiswayo, Somila , Nyokong, Tebello , Song, Yuting , Xu, Haijun , Liang, Xu
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186791 , vital:44534 , xlink:href="https://doi.org/10.1016/j.dyepig.2019.107740"
- Description: Eight porphyrin dimers with various functional bridging blocks and chiral amide-bonds were synthesized and characterized. An analysis of the spectroscopy and electrochemistry has been carried out to demonstrate that the chiral properties can be modified by changing the interchromophoric through-space coupling distance between the two porphyrin chromophores by introducing various bonding and bridging blocks.
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- Date Issued: 2019
Synthesis, characterization and photodynamic activity of Sn (iv) triarylcorroles with red-shifted Q bands
- Authors: Babu, Balaji , Prinsloo, Earl , Mack, John , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187521 , vital:44668 , xlink:href="https://doi.org/10.1039/C9NJ03391B"
- Description: Two Sn(IV) triarylcorroles were synthesised and characterized. The absorption spectrum of a meso-thien-2-yl substituted tin(IV)corrole (1-Sn) is red shifted compared to its phenyl analogue (2-Sn) and shows no sign of aggregation in solution. 1-Sn and 2-Sn exhibited singlet oxygen quantum yields of 0.87 and 0.54 in DMF, and have a triplet lifetime of 31 and 50 μs, respectively. Time dependent cellular uptake in MCF-7 cells for 1-Sn reached a peak at 24 h, and 1-Sn was found to be more lipophilic than 2-Sn. 1-Sn showed good photo-cytotoxicity on exposure to a Thorlabs 625 nm LED with an IC50 value of 3.2 μM and remained inactive in the dark.
- Full Text:
- Date Issued: 2019
Testing the thermal limits of Eccritotarsus catarinensis: a case of thermal plasticity
- Authors: Porter, Jordan D , Owen, Candice A , Compton, Stephen G , Coetzee, Julie A
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/417533 , vital:71461 , xlink:href="https://doi.org/10.1080/09583157.2019.1572712"
- Description: Water hyacinth is considered the most damaging aquatic weed in South Africa. The success of biocontrol initiatives against the weed varies nation-wide, but control remains generally unattainable in higher altitude, temperate regions. Eccritotarsus catarinensis (Hemiptera: Miridae) is a biocontrol agent of water hyacinth that was first released in South Africa in 1996. By 2011, it was established at over 30 sites across the country. These include the Kubusi River, a site with a temperate climate where agent establishment and persistence was unexpected. This study compared the critical thermal limits of the Kubusi River insect population with a laboratory-reared culture to determine whether any physiological plasticity was evident that could account for its unexpected establishment. There were no significant differences in critical thermal maxima (CTmax) or minima (CTmin) between sexes, while the effect of rate of temperature change on the thermal parameters in the experiments had a significant impact in some trials. Both CTmax and CTmin differed significantly between the two populations, with the field individuals tolerating significantly lower temperatures (CTmin: −0.3°C ± 0.063 [SE], CTmax: 42.8°C ± 0.155 [SE]) than those maintained in the laboratory (CTmin: 1.1°C ± 0.054 [SE], CTmax: 44.9°C ± 0.196 [SE]). Acclimation of each population to the environmental conditions typical of the other for a five-day period illustrated that short-term acclimation accounted for some, but not all of the variation between their lower thermal limits. This study provides evidence for the first cold-adapted strain of E. catarinensis in the field, with potential value for introduction into other colder regions where water hyacinth control is currently unattainable.
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- Date Issued: 2019
The attitudes of riparian communities to the presence of water hyacinth in the Wouri River Basin, Douala, Cameroon
- Authors: Voukeng, Kenfack S N , Weyl, Philip , Hill, Martin P , Chi, N
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/423822 , vital:72096 , xlink:href="https://doi.org/10.2989/16085914.2018.1538868"
- Description: Since publication of the first record of Eichhornia crassipes in Cameroon in 1997, the weed has become highly invasive in the Wouri River Basin. Between June and September 2014, a socio-economic survey using participatory and qualitative methods was undertaken in the riparian villages of the Wouri River Basin to assess the perception of respondents to the presence of water hyacinth. The survey revealed that water hyacinth was a significant threat to activities along the river, which included fishing, sand extraction and river transportation. The presence of water hyacinth mats reduced catch rates of several common fish species, river transportation by 75%, and significantly reduced the income for sand extraction. Cameroon employs manual clearing of water hyacinth; however, respondents indicated they would consider other control methods, provided they do not have any negative impacts.
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- Date Issued: 2019
The contribution of land tenure diversity to the spatial resilience of protected area networks
- Authors: de Vos, Alta , Cumming, George S
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/416421 , vital:71347 , xlink:href="https://doi.org/10.1002/pan3.29"
- Description: The relationship between diversity and resilience is relatively well‐established for ecological systems, but remains much less explored for socio‐economic systems. Institutional diversity can have particular relevance for protected areas, whose managerial responses to environmental change depend on their legal basis, ability to make and enforce rules and socio‐political acceptance and endorsement. 2. Protected area expansion strategies are increasingly turning to private land con‐ servation to increase the configuration and connectivity of national protected area networks. Yet, we know little about the relative role of privately owned pro‐ tected areas in protecting threatened and poorly protected (under‐represented) habitats, and in the overall connectivity of the national protected area network. 3. We present an empirical assessment of protected area tenure diversity across South Africa.
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- Date Issued: 2019
The contribution of NTFPs to rural livelihoods in different agro-ecological zones of South Africa
- Authors: Mugido, Worship , Shackleton, Charlie M
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182308 , vital:43819 , xlink:href="Commonwealth Forestry Association"
- Description: In South Africa, there is extensive NTFP trade within communities and via external markets. However, there is a limited indication of the proportion of all households trading one or more NTFPs, and how it varies in relation to local context. Therefore, this study sought to establish the proportion of households trading in NTFPs in sites of different distances to urban markets and agro-ecological zones of South Africa. The results showed that about 6.4% households reported selling NTFPs for various reasons, with many (22%) citing the need to earn cash income and limited employment opportunities (16.9%). Even though the returns from trading NTFPs are relatively low, every earning is very important to many cash-strapped rural households. This was demonstrated by the fact that many sellers of NTFPs used their earnings to augment household income and cover their living expenses.
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- Date Issued: 2019
The meaning and practice of stewardship in South Africa
- Authors: Cockburn, Jessica , Cundill, Georgina , Shackleton, Sheona , Rouget, Mathieu
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/390683 , vital:68574 , xlink:href="http://dx.doi.org/10.17159/sajs.2019/5339"
- Description: Stewardship offers a means of addressing social-ecological sustainability challenges, from the local to the global level. The concept of stewardship has had various meanings attached to it over time, and the links between the theory and practice of stewardship are not well understood. We sought to characterise the practice of stewardship in South Africa, to better understand the relationship between theory and practice. We found that practitioners’ understandings of stewardship coalesce around two core notions: the idea of stewardship as ‘responsible use and care’ of nature, and stewardship as a ‘balancing act’ between stewards’ use of natural resources for agricultural production and their responsibility to protect and manage the wider ecosystem. Stewardship practice in South Africa is strongly influenced by the biodiversity stewardship tool; however, many practitioners are integrating biodiversity stewardship with other approaches. These emerging social-ecological stewardship initiatives operate at landscape-level and work towards integrated social and ecological stewardship outcomes, by facilitating collaboration among diverse stakeholders. Further research is needed to better understand what is required to support these integrated, collaborative and cross-sectoral initiatives. Policy mechanisms that facilitate integrated place-based stewardship practice can contribute to expanding the practice of biodiversity stewardship in South Africa.
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- Date Issued: 2019
The obstinate notion that higher education is a meritocracy
- Authors: Sobuwa, Simpiwe , McKenna, Sioux
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187150 , vital:44574 , xlink:href="https://doi.org/10.14426/cristal.v7i2.184"
- Description: Student success is an enormous concern in light of the high drop-out rates in South African universities. There is a wealth of local and international research which provides complex explanations for these statistics, but the common-sense understanding is that those students who have the right attributes and who work hard will do well. While the notion of higher education as a meritocracy is pervasive, it is invalid given the effects of numerous other mechanisms at play in the students' educational experiences. This article draws from the literature to discuss the problems of the meritocratic explanation in how it fails to sufficiently account for the centrality of agency and the ways in which this intersects with societal structures. We argue that more useful understandings of student success and failure require social theory that acknowledges the complexities underpinning student success or failure.
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- Date Issued: 2019
The photo-physicochemical properties and in vitro photodynamic therapy activity of differently substituted-zinc (II)-phthalocyanines and graphene quantum dots conjugates on MCF7 breast cancer cell line
- Authors: Nene, Lindokuhle C , Managa, Muthumuni E , Oluwole, David O , Mafukidze, Donovan M , Sindelo, Azole , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187449 , vital:44653 , xlink:href="https://doi.org/10.1016/j.ica.2019.01.012"
- Description: Several differently substituted Zn(II) phthalocyanines (ZnPcs) were prepared and conjugated to GQDs. The photophysical properties were determined for both the Pcs and their respective conjugates including the fluorescence/triplet quantum yields and lifetimes as well as the singlet oxygen generating abilities. Upon conjugation to GQDs, the fluorescence of the Pcs decreased (insignificant decrease in some cases), with an increase in the triplet quantum yields. However, the singlet quantum yields of the Pcs in the conjugates did not show an increase with the increase in the triplet quantum yields, this is suspected to be due to the screening effect. The cytotoxicity of the complexes in vitro decreased upon conjugation, as a result of the reduced actual number of Pcs units provided in the conjugate for therapy. Upon introduction of cationic charges, the photodynamic therapy activity of the complexes increased.
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- Date Issued: 2019
The photophysicochemical properties and photodynamic therapy activity of phenyldiazenyl phenoxy substituted phthalocyanines when incorporated into Pluronic® F127 micelles
- Authors: Motloung, Banele M , Sekhosana, Kutloano E , Managa, Muthumuni , Prinsloo, Earl , Nyokong, Tebello
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186769 , vital:44532 , xlink:href="https://doi.org/10.1016/j.poly.2019.114157"
- Description: The synthesis, photophysicochemical properties and photodynamic activity (PDT) of 4(4-phenyldiazenyl) phenoxy substituted indium (III) (InPc) and zinc (ZnPc) phthalocyanines when alone or incorporated into Pluronic_ F127 micelles are presented in this study. The InPc exhibited higher singlet oxygen (UD) at 0.47 compared to the ZnPc at 0.20 in dimethylsulfoxide. The UD values in the presence of Pluronic_ F127 and in water, were 0.32 for InPc and 0.09 for ZnPc. The triplet quantum yields (UT) were 0.92 for InPc and 0.32 for ZnPc in DMSO. The PDT activity followed the same trend as the singlet oxygen quantum yields. At the highest concentration, InPc in Pluronic_ F127 gave 22% cell viability compared to 34% for complex ZnPc. The partition coefficient Kp values were determined using the water and octanol system. InPc had a larger Kp suggesting that it is more likely to be taken up by the cancer cells, hence it exhibited better PDT activity.
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- Date Issued: 2019
The relative representation of ecosystem services and disservices in South African newspaper media
- Authors: Mclellan, V , Shackleton, Charlie M
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/179699 , vital:43162 , https://doi.org/10.1080/26395916.2019.1667442
- Description: Newspapers are key information sources and may influence both public opinion and policy. Previous studies have analysed the portrayal of ecosystem disservices in newspapers, but none have assessed the relative coverage between disservices and services, or how it might have changed over time. We report on the relative frequency and depiction of ecosystem services and disservices in South African, English newspapers over a 15-year period. We used a SABINET search complemented by key-informant interviews with environmental journalists. For each article we recorded if it covered ecosystem services or disservices, the type of service or disservice, and article tone and length. Overall, 2,201 articles were found, of which 25% were on services and 75% on disservices. The number of articles per year declined over the 15-year period for services, but not disservices. The most common services were energy and craft materials, food production, recreation and culture, and disservices were human health, heat waves and floods. Articles on ecosystem services were 25–40% longer than those on disservices. Article lengths on both declined over the 15 years. The greater reporting of ecosystem disservices over services is likely to influence public opinion and environmental decision-making accordingly.
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- Date Issued: 2019
The role of invasive alien species in shaping local livelihoods and human well-being: A review
- Authors: Shackleton, Ross T , Shackleton, Charlie M , Kull, Christian A
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180280 , vital:43349 , xlink:href="https://doi.org/10.1016/j.jenvman.2018.05.007"
- Description: Invasive alien species are a well-recognised driver of social-ecological change globally. Much research has focused on ecological impacts, but the role of invasive species for livelihoods and human well-being is less well known. Understanding the effects (benefits and costs) of invasive species on livelihoods and human well-being is important for guiding policy formulation and management. Here we review the literature on the role of invasive species in livelihoods to assess what is known, identify knowledge gaps and provide recommendations for future research. Literature was collected using key word searches and included both journal publications and grey literature. Slightly less than half (48%) of species studied had both substantial positive and negative impacts on local livelihoods (e.g. Australian Acacia spp. species; Camelus dromedaries; Lantana camara; Prosopis spp.), with 37% inducing mainly costs (Chromolaena odorata; Lissachatina fulica; Opuntia stricta) and 16% producing mainly benefits (Opuntia ficus-indica; Acacia spp.). Some species, such as Acacia dealbata, fell into different categories depending on the social-ecological context. Key benefits or services included the provision of fuelwood, fodder, timber and food products for local households communities and to a lesser extent supporting and regulating services such as soil improvement and shade. A number of species also provided cultural services such as recreation and spiritual values and provided many with an opportunity to earn a cash income. However, invasive species also harm livelihoods and increase vulnerability through encroaching on land and reducing mobility or access. They can also decrease the supply of natural resources used by households and reduce agricultural production (livestock and/or crops) which can result in losses of income and increased vulnerability. Furthermore, some invasive species were seen to have negative implications for human health and safety and reduce the cultural value of landscapes. Economic impacts on livelihoods as a result of invasive species were highly variable and very dependent on the social-ecological contexts. These negative implications can reduce resilience and adaptive capacity of households and communities thus increasing their vulnerability to change. Drawing on case studies we highlight that efforts for managing invasive species need to safeguard livelihood benefits while mitigating negative impacts. In concluding we highlight future research and policy needs on the topic of invasive species, livelihoods and human well-being.
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- Date Issued: 2019
The role of local economic development in the empowerment of women in rural areas : the case of Makana Municipality
- Authors: Hani, Nomkita Octavia
- Date: 2019
- Subjects: Economic development , Women in development
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/19772 , vital:43237
- Description: The aim of the study was to explore the role of Local economic development (LED) in empowering rural women in Makana Municipally. The researcher intended to achieve the following objectives (i) to assess the role of LED among the rural women of Makana Municipality in strengthening economic development ii) to explore the LED challenges confronted by the community and the municipality in the implementation of economic empowerment programs that will create economic opportunities for rural women iii) to identify the way forward in enhancing the LED strategy to empower rural women to enable them participate in economic programs of the local Municipality that will benefit them and the community. The study adopted a qualitative approach and purposive sampling methods which were used to select samples for the study. Open ended questions were used in face to face interviews and focus groups to collect data in Makana Municipality. The study findings indicated that while women are part LED activities in the Makana municipality, the benefits that accrue to them are still minimal and trickling down to very few of them because of egoism and nepotism, corruption and crime, favouritism and poor communication. There is a great need for interventions requiring regular visits from LED officials and provision of educational programs in the local language, to enable the women to have a clear understanding of the benefits that accrue to them from LED projects, notwithstanding the opportunities open to them for participation. The study then proposed recommendations to empower women which include making resources available for their empowerment, such as, the provision of skill development programs, knowledge and information distribution, reviewing of the LED policy, infrastructure development and access to markets. , Thesis (MCom) -- Faculty of Management and Commerce, 2019
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- Date Issued: 2019
The South America tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), spreads its wings in Eastern Africa: distribution and socioeconomic impacts
- Authors: Aigbedion-Atalor, Pascal O , Hill, Martin P , Zalucki, Myron P , Obala, Francis , Idriss, Gamal E , Midingoyi, Soul-Kifouly G , Chidege, Maneno , Ekesi, Sunday , Mohamed, Samira Abuelgasim
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/423859 , vital:72099 , xlink:href="https://doi.org/10.1093/jee/toz220"
- Description: Following the arrival of Tuta absoluta Meyrick in the eastern African subregion in 2012, several studies have shown numerous ecological aspects of its invasion. We investigated the impact of T. absoluta on people’s livelihoods across four counties of Kenya. Here, 200 farmers in the country were interviewed in person using semistructured questionnaires. In addition to livelihood surveys, T. absoluta distribution was mapped between 2016 and 2018 to determine its current distribution across four countries (Kenya, Sudan, Tanzania, and Uganda) in the subregion. Albeit a recent invader, T. absoluta is abundant and distributed throughout the subregion and is viewed as the worst invasive alien species of agriculturally sustainable livelihoods by tomato farmers. The arrival of T. absoluta in the subregion has resulted in livelihood losses and increased both the cost of tomato production and frequency of pesticide application. We recommend the implementation of biological control along, with other control measures in an integrated approach, against T. absoluta in the subregion, where its impact on sustainable livelihoods is serious and long-term control strategies are required to curb its detrimental effects.
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- Date Issued: 2019
The Stinking Ontology of Sh#t in the Water: Higher Education Public Pedagogy and “Existance”?
- Authors: Lotz-Sisitka, Heila
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182754 , vital:43871 , xlink:href="http://doi.org/10.1089/sus.2019.29161"
- Description: “Existance” is not a spelling mistake. It is a word from Soweto street poet Zachariah Rapola’s poem, questioning our “stance in existence” . In the context of this essay, the poem raises the challenging perspective of our “stance in existence.” for engaging with the SDGs. The SDGs set a range of clear targets, but in doing so, they fail to give a good account of the stinking ontology of some of the issues to be dealt with, and thus lack a certain sense of realism.
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- Date Issued: 2019
The Trope of the Child: Rereading Trauma, Subjectivity and Embodiment in Contemporary Child-Centred African Narratives by Ahmadou Kourouma, Chris Abani, K. Sello Duiker and Yvonne Vera
- Authors: Njovane, Thandokazi
- Date: 2019
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/164557 , vital:41134 , doi:10.21504/10962/164557
- Description: Thesis (PhD)--Rhodes University, Humanities, Literary Studies in English, 2019
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- Date Issued: 2019
Thermal plasticity and microevolution enhance establishment success and persistence of a water hyacinth biological control agent
- Authors: Griffith, Tamzin C , Paterson, Iain D , Owen, Candice A , Coetzee, Julie A
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/424866 , vital:72190 , xlink:href="https://doi.org/10.1111/eea.12814"
- Description: Aspects of the thermal physiology of the water hyacinth biological control agent Eccritotarsus catarinensis Carvalho (Hemiptera: Miridae) have been extensively investigated over the past 20 years to understand and improve post-release establishment in the field. Thermal physiology studies predicted that the agent would not establish at a number of cold sites in South Africa, where it has nonetheless subsequently established and thrived. Recently, studies have begun to incorporate the plastic nature of insect thermal physiology into models of agent establishment. This study determined whether season and locality influenced the thermal physiology of two field populations of E. catarinensis, one collected from the hottest site where the agent has established in South Africa, and one from the coldest site. The thermal physiology of E. catarinensis was significantly influenced by season and site, demonstrating a degree of phenotypic plasticity, and that some post-release local adaptation to climatic conditions has occurred through microevolution. We then determined whether cold acclimation under laboratory conditions was possible. Successfully cold-acclimated E. catarinensis had a significantly lower critical thermal minimum (CTmin) compared to the field cold-acclimated population. This suggests that cold acclimation of agents could be conducted in the laboratory before future releases to improve their cold tolerance, thereby increasing their chance of establishment at cold sites and allowing further adaptation to colder climates to occur in the field. Although the thermal tolerance of E. catarinensis is limited by local adaptations to climatic conditions in the native range, the plastic nature of the insect's thermal physiology has allowed it to survive in the very different climatic conditions of the introduced range, and there has been some adaptive change to the insect's thermal tolerance since establishment. This study highlights the importance of plasticity and microevolutionary processes in the success of biological control agents under the novel climatic conditions in the introduced range.
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- Date Issued: 2019
Think Piece. Situating Education for Sustainable Development in southern African philosophy and contexts of social-ecological change to enhance curriculum relevance and the common good
- Authors: Pesanayi, Tichaona V , O'Donoghue, Rob B , Shava, Soul
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/388105 , vital:68307 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/187217"
- Description: The study opens with a brief review of how education in colonial southern Africa was steered by a succession of externally framed abstractions that have been implemented within the prevailing hegemony of western modernisation that dominated and marginalised indigenous cultures. It probes how, within an expanding functionalist framework, Education for Sustainable Development (ESD) has been similarly constituted as a proposition for implementation. Here the supposition is that implementing ESD as an intervention will transform education into an inclusive and collaborative pedagogy that will shape competences for participants to transform society towards a sustainable future. In an effort to explore the possibility of making a break from a succession of education imperatives functioning as ‘salvation narratives’ to put things right in Africa, the study explores ESD from a more situated and emergent vantage point within African landscapes, philosophy and cultural practices. This requires a shift from a view of ESD as a perspective to be brought in and enacted to foster change, to ESD as a situated engagement in education as a process where relevance is deliberated and brought out in quality education with high order skills. This perspective exemplifies working with a more fully situated framing of deliberative social learning for the common good. It is explored here to contemplate how socio-cultural processes of deliberative ethics and co-engaged reflexive processes of learning-led change might emerge. Here, also, using a capabilities approach might provide useful starting points for ESD as an expansive process of transformative social learning.
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- Date Issued: 2019
Towards a biological profile for South African perinatal remains: osteological and genetic perspectives
- Authors: Thornton, Roxanne
- Date: 2019
- Subjects: Identification , Forensic osteology , Methylation , RNA , Autopsy
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/68102 , vital:29198 , DOI 10.21504/10962/68102
- Description: Forensic identification of abandoned and suspected infanticide cases admitted to the South African Forensic Pathology Services is often impossible due to decomposition of the remains. In these cases, investigation of suspected criminal activity is almost never pursued. Ancillary tests in the form of anthropological and molecular analyses can assist with the forensic identification of perinatal remains. To provide fundamental information about bone development of perinatal skeleton, osteological and genetic techniques focusing on the pars basilaris, pars lateralis, sternal rib and left femur were used. Samples were obtained from unidentified and unclaimed remains originating from the Johannesburg Forensic Pathology Service (JFPS). To provide a biological age to individuals in the collection, dental aging was used to categorize remains for comparisons with anthropological and molecular data. A molecular protocol was designed to sex individuals using the X-linked G6PD and Y-linked SRY genes. Bone development was studied using osteometric and morphological data of dry bone remains coupled with bone mineral density analysis (Micro-CT). The methylation levels of CpG rich sites within the promoter region of selected bone-associated genes were incorporated to examine silencing of genes during development. Osteological results support the use of the pars basilaris, pars lateralis and femur for age-at-death estimations as well as provide the foundation for dry bone aging criteria for South African individuals. Data compared with established skeletal aging standards indicated developmental differences between populations. Through the use of animal models and the perinatal sternal rib tissue, insights and precautions into the use of post mortem bone derived RNA for forensic applications is communicated. The methylation status of CpG rich sites within the promoter regions support the hypothesis for interdependent machinery involving selected genes during early bone development. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2019
- Full Text:
- Date Issued: 2019