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An investigation of teachers’ experiences of a Geoboard intervention programme in area and perimeter in selected Grade 9 classes: a case study

  • Authors: Mkhwane, Fezeka Felicia
  • Date: 2018
  • Subjects: Mathematics -- Study and teaching (Secondary) -- South Africa , Teachers -- Training of -- South Africa , Manipulatives (Education) , Effective teaching , Area measurement , Perimeters (Geometry) , Problem solving -- Study and teaching , Geoboard Intervention Programme , RUMEP
  • Language: English
  • Type: text , Thesis , Masters , MEd
  • Identifier: http://hdl.handle.net/10962/61646 , vital:28045
  • Description: The study was undertaken with three Grade 9 teachers at three selected schools which are part of RUMEP’s Collegial Cluster Schools’ programme that I coordinate. Collegial clusters are communities of teachers who aim at improving their practice by working on their own professional development. The purpose of this study was to investigate the selected Grade 9 teachers’ experiences of a Geoboard intervention programme. It also wanted to investigate the role that a Geoboard can play in the teaching and learning of area and perimeter of two-dimensional shapes. The research was a case-study within the interpretive paradigm. A variety of data collection techniques was used. These included baseline assessment tasks, observations during the intervention programme, post intervention assessment tasks and semistructured interviews with the participating teachers and a few learners from each participating school. The collected data was analysed using both the quantitative and qualitative methods. My research findings reveal that a Geoboard, as a manipulative, developed confidence in the participating teachers. In the interviews with teachers, it transpired that teachers’ skills in teaching area and perimeter of two-dimensional shapes had been sharpened. According to the interviews with learners, the use of a Geoboard led to better conceptual understanding of the area and perimeter, as learners no longer had to rely on formulae. Kilpatrick et al. (2001) refer to conceptual understanding as an integrated functional grasp of mathematical ideas. The post intervention assessment task showed a positive shift in learners’ performance. The average learner performance improved from 29% in the baseline assessment task to 61% in the post intervention assessment task. This shows that the use of a Geoboard led to meaningful learning of area and perimeter of two-dimensional shapes. The overall research findings reveal that the use of manipulatives has a positive impact in the teaching and learning of area and perimeter. Learners’ responses to the interview questions showed that there was better understanding of the two concepts, which enabled them to construct their own knowledge. They further said the Geoboard allowed them to be hands-on, which contributed to their active involvement in the lesson.
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  • Date Issued: 2018

An investigation of the challenges associated with conducting home visits in rural areas, from the lenses of social workers: the case of Raymond Mhlaba Municipality - Eastern Cape, South Africa

  • Authors: Nguza, Zizipho Zintle https://orcid.org/0000-0001-6559-3183
  • Date: 2018
  • Subjects: Home-based family services http://id.loc.gov/authorities/subjects/sh89005719 , Social workers http://id.loc.gov/authorities/subjects/sh85124114 , Sociology, Rural http://id.loc.gov/authorities/subjects/sh85124229
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/19523 , vital:43135
  • Description: This study strove to understand the challenges encountered by social workers in conducting home visits in rural areas of the Eastern Cape in Raymond Mhlaba Municipality. The intention was to achieve the following objectives; (i) establish the kind of problems that social workers attend to when conducting home visits in rural areas, (ii) investigate the challenges that social workers encounter in the provision of home visits in rural areas, (iii) establish the support services offered to the social workers by their organisations; from the lenses of both social workers and supervisors. The study employed the qualitative approach and was guided by a qualitative research design in the form of a case study. It also employed in-depth one-on-one interviews complemented by both focus group discussions and social work participants as methods of data collection. The study used non-probability sampling technique, specifically the purposive sampling of twenty five (25) social work stakeholders. The sample comprised twenty (20) social workers, both female and male participants and five (5) supervisors. Data was analysed qualitatively through content thematic data analysis which used interpretative approaches and textual presentation. The study revealed the following findings: that social workers in Raymond Mhlaba municipality dealt with an immense range of social problems such as poverty, unemployment, crime, HIV and AIDS, orphanhood, child headed households, marital discord, violence against women and children, abuse of families and persons with disability and mismanagement of social grants. The study recommends employee assistance programmes so that independent counselling and supportive services could be provided for social workers working in rural areas. Regular in-service training programmes can play a vital role in helping staff handle pressure and avoid occupational stress. , Thesis (M Soc Sc) (Social Work) -- University of Fort Hare, 2018
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  • Date Issued: 2018

An investigation of the correlation of mitochondrial biogenesis, mitochondrial DNA methylation, mitochondrial network topology and adipogenesis in the human adipose-derived mesenchymal stromal stem cell model

  • Authors: Kadye, Rose
  • Date: 2018
  • Subjects: Uncatalogued
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/62637 , vital:28222
  • Description: Expected release date-April 2019
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  • Date Issued: 2018

An investigation of the informal market value chain for prickly pear (Opuntia ficus-indica) in Nelson Mandela Bay, Eastern Cape

  • Authors: Ntsonge, Sinazo
  • Date: 2018
  • Subjects: Opuntia ficus-indica -- South Africa -- Nelson Mandela Bay Municipality , Alien plants -- Economic aspects -- South Africa -- Nelson Mandela Bay Municipality , Women heads of households -- South Africa -- Nelson Mandela Bay Municipality , Poor -- South Africa -- Nelson Mandela Bay Municipality , Informal sector (Economics) -- South Africa -- Nelson Mandela Bay Municipality , Sustainable Livelihoods Framework
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/62894 , vital:28308
  • Description: The use of alien plant species as part of the livelihood resources of poor people raises conflicts with national legislation, which views these plants as threats to native plant biodiversity. However, there is also increasing body of literature on the contribution that some of these plants make to the livelihoods of poor people. The level of significance of some alien plant species to livelihoods is mostly highlighted in the case of female market participants who are in a position of household headship. Since most African cultures dictate the role of females as solely being that of homemaker while males are assigned the role household headship and breadwinner, women often find themselves having to shoulder the household responsibilities when the household head is no longer there. This was the case in the Nelson Mandela Bay informal prickly pear market that this study sought to investigate. Even though there were also male participants in the prickly pear market, the majority of participants in the market were female who also mentioned they were the sole breadwinner for their households. This study investigated the economic contribution that the prickly pear (Opuntia ficus-indica) informal market makes to the livelihoods of people living in the Nelson Mandela Bay. The significance of the market’s contribution to their livelihoods was examined through using the Sustainable Livelihoods Framework. The study revealed that although the prickly pear income was largely supplementary due to it being available for only three months of the year, the income was a safety net resource for the market participants who had limited access to other sources of income. The results also highlighted the reasons people were engaging in the informal prickly pear market. The main reason that was mentioned was unemployment. Through a livelihoods analysis using the Sustainable Livelihoods Framework, it was revealed that the other factors that were contributing to their unemployment were low levels of education, low levels of marketable skills, and old age. The study revealed through calculations of the estimated economic value of each market activity the potential of the prickly pear to be used as a poverty fighting tool. Although the results of this study only highlight the economic value of the prickly pear to people in a small area compared to the rest of the province and the country, the informal market’s significance still presents a strong case for the establishment of an agroprocessing industry, which would support the production of value-added products. Since the largest populations of the prickly pear in Uitenhage are currently under effective control by the cochineal species, promotion of its economic value instead of eradicating it without considering its value to the livelihoods of the people in the market could also ensure that its populations are kept under control. Job creation in the agroprocessing industry would not only improve the livelihoods of those involved in the market, but would also feed into the national economy instead of taking from it via the costs incurred during clearing.
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  • Date Issued: 2018

An investigation of the leadership practices and organizational culture at a private Christian school

  • Authors: Babu, Bithun
  • Date: 2018
  • Subjects: Church schools -- South Africa -- Eastern Cape , Leadership , Corporate culture
  • Language: English
  • Type: text , Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10962/62155 , vital:28133
  • Description: The purpose of this study is to investigate the leadership practices and organizational culture at a private Christian school in the Eastern Cape. A preliminary review of leadership literature suggested that traces of servant leadership may be apparent at the organization. Thus servant leadership will form a key focus area for exploration in this study. An analysis of this nature can make one aware of the influence leadership has in shaping the organizational culture of an institution. This in turn can be used to inform the future thinking around leadership efforts with respect to culture formation within an organization. The issue was addressed by consulting various articles to view the issue from different perspectives. The school served as a vehicle to explore the tenets of leadership and organizational culture. The study will take the form of a descriptive quantitative study. It was concluded that leadership plays a significant role in establishing the culture at an organization. However, leadership is not the only factor that shapes the organizational culture of an institution. The beliefs and values of the organization also has a role in shaping the overall culture and identity of an organization.
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  • Date Issued: 2018

An investigation of the teaching of reading in isiXhosa in three Grade 1 classrooms in the Eastern Cape, South Africa

  • Authors: Magadla, Noluthando
  • Date: 2018
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/63408 , vital:28408
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  • Date Issued: 2018

Analysis of the human HSP70-HSP90 organising protein (HOP) gene - characterisation of the promoter and identification of a novel isoform

  • Authors: Mattison, Stacey
  • Date: 2018
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/62821 , vital:28296
  • Description: Expected release date-April 2020
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  • Date Issued: 2018

Antibiotic-Resistant Pathogenic Escherichia Coli Isolated from Rooftop Rainwater-Harvesting Tanks in the Eastern Cape, South Africa

  • Authors: Malema, Mokaba Shirley , Abia, Akebe Luther King , Tandlich, Roman , Zuma, Bonga , Kahinda, Jean-Marc Mwenge , Ubomba-Jaswa, Eunice
  • Date: 2018
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/71729 , vital:29931 , https://doi.org/10.3390/ijerph15050892
  • Description: Although many developing countries use harvested rainwater (HRW) for drinking and other household purposes, its quality is seldom monitored. Continuous assessment of the microbial quality of HRW would ensure the safety of users of such water. The current study investigated the prevalence of pathogenic Escherichia coli strains and their antimicrobial resistance patterns in HRW tanks in the Eastern Cape, South Africa. Rainwater samples were collected weekly between June and September 2016 from 11 tanks in various areas of the province. Enumeration of E. coli was performed using the Colilert®18/Quanti-Tray® 2000 method. E. coli isolates were obtained and screened for their virulence potentials using polymerase chain reaction (PCR), and subsequently tested for antibiotic resistance using the disc-diffusion method against 11 antibiotics. The pathotype most detected was the neonatal meningitis E. coli (NMEC) (ibeA 28%) while pathotype enteroaggregative E. coli (EAEC) was not detected. The highest resistance of the E. coli isolates was observed against Cephalothin (76%). All tested pathotypes were susceptible to Gentamicin, and 52% demonstrated multiple-antibiotic resistance (MAR). The results of the current study are of public health concern since the use of untreated harvested rainwater for potable purposes may pose a risk of transmission of pathogenic and antimicrobial-resistant E. coli.
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  • Date Issued: 2018

Aquatic habitat shift assessment in a groundwater-fed semi-arid stream: an investigation into the response of Karoo hydroecology to system variability

  • Authors: Ellis, Natalie
  • Date: 2018
  • Subjects: Aquatic habitats -- South Africa -- Karoo , Arid regions -- South Africa -- Karoo , Biotic communities -- South Africa -- Karoo , Stream ecology -- South Africa -- Karoo
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/61882 , vital:28072
  • Description: From introduction: The subject of biological response to changes in aquatic habitat is one which has been well explored in many regions of the world. Examples include work in south east Spain by Mellado Diaz et al. (2008) and Oliva-Paterna et al. (2003), in western United States of America by Hauer and Lorang (2004), and in West Germany by Meyer et al. (2003). Similarly, a number of studies have been conducted in semi-arid regions, exploring elements such as erosion, climate, lithology and landscape formations (e.g. Boardman et al., 2013; Le Maitre et al., 2007; Meyer et al., 2003). However, apart from the study by Uys (1997), and Uys and O’Keeffe (1997), there is a noticeable lack of literature on aquatic habitat shifts in semi-arid stream systems, despite these systems being recognised for their high natural variability. This study provides a base-level approach to conducting habitat shift assessments in a semi-arid stream system and monitoring the hydroecological responses to system variability.
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  • Date Issued: 2018

Art topples monuments: artistic practice and colonial/postcolonial relations in the public space of Luanda

  • Authors: Siegert, Nadine
  • Date: 2018
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/147014 , vital:38585
  • Description: Even though there have been very few modern and contemporary artworks in the urban space of Luanda in the years after independence in 1975—and especially after the end of the civil war in 2002—there are two works by Angolan artists that are of particular interest: the sculpture Mitologias II (1984) by António Ole (b. 1951) and the photographic series Redefining the Power (2011) by Kiluanji Kia Henda (b. 1978). Both works address the possibility of using contemporary art as a symbolic form of the replacement of power, since both are built on pedestals that had previously supported monuments of Portuguese colonial power. They might, therefore, be read as a form of substitution for monuments that would commemorate and celebrate independence or the end of colonialism. This article also discusses whether these two artworks can also be regarded as counter-monuments and this contributes to the discourse on the visual and material culture of Lusophone Africa.
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  • Date Issued: 2018

Aspects Allocentristes de l’Humanisme dans l’Univers Romanesque de Williams Sassine

  • Authors: Dami, Emmanuel Naancin
  • Date: 2018
  • Subjects: Sassine, Williams, 1944-1997 -- Criticism and interpretation , Guinean fiction (French) -- 20th century -- History and criticism , Humanism in literature , Human beings in literature , Postcolonialism in literature , Existentialism in literature
  • Language: French , English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/61957 , vital:28089
  • Description: The human being, his behaviour and more importantly, his very essence have, for time immemorial, proven to be enigmatic to many a man and to researchers in particular. Consequently, the need for a thorough and more profound understanding of man has made him the epicentre of epistemic investigations across many academic disciplines. This, unfortunately, does not seem to have shaded bright lights on the grey areas bordering on his nature to his behavior. This, in turn, opens up other windows requiring further probes. For instance, proponents of the Neo-classical economic school contend that the human being is homo oeconomicus. This implies that man is intrinsically egocentric and a rational being whose decisions are based on informed choices driven by his urge for maximal utility geared towards his personal satisfaction (O’Boyle 2009; Caruso 2012). This stance invalidates man’s ability to do ‘disinterested good’ in any form. African francophone literature is replete with different and diverse images of man, his behaviour and existential conditions: sufferings and struggles. It, therefore, constitutes, inter alia, a laboratory in which researchers undertake investigative endeavours. This thesis beams its floodlights on the allocentric aspects of humanism in the novels of Williams Sassine. Thus, using the phenomenological and ‘clavieniste’ lenses as overarching operational theories, the thesis investigates Sassine’s novels with the view to shading a ray of light on the ‘humanistic man’ especially the allocentric dimensions of his nature and comportment. Emphasis is laid on the motives and motivations underlying the individual and the in-group struggle of the sassinien heroes in the emancipation of their society from the shackles of colonial and postcolonial domination, exploitation and subjugation resulting in self-determination and the subsequent disenchantment. Furthermore, the thesis examines the nature and character of human charity, generosity and sacrifices among the characters in the novels. In conclusion, the thesis establishes, through an x-ray of the nature of actions and decisions of certain characters in the novels, the examination of the conscious and subconscious intentions underlying these same actions and decisions which, on a face value, are apparently altruistic, that the sassinien heroes’ efforts and sacrifices are geared towards the common and greater good. This invariably means that man is, indeed, capable of posing disinterested acts of charity and bringing succour, devoid of any ulterior motives for personal gain, to his fellow humans. The position of the Neo-classical economists is consequently over-assuming, sweeping and tad generalizing. The sassinien characters have demonstrated beyond reasonable doubt that they are humanists. Their nature, the remote and immediate causes of their fights, the goals and objectives of their struggles and their spirit of abnegation have indeed proven that “human beings have the right and the responsibility to give meaning and shape to their own lives. [They have stood] for the building of a more humane society through an ethics based on the human and other natural values in a spirit of reason and free inquiry through human capabilities” (AHA 2017 : 3).
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  • Date Issued: 2018

Aspects of the nutritional physiology of the perlemoen Haliotis midae (L.) and red abalone H. rufescens (Swainson)

  • Authors: Kemp, Justin Oliver Gordon
  • Date: 2018
  • Subjects: Haliotis midae , Haliotis midae fisheries , Red abalone , Haliotis midae -- Feeding and feeds , Red abalone -- Feeding and feeds , Haliotis midae -- Nutrition -- Requirements , Red abalone -- Nutrition -- Requirements , Haliotis midae -- Metabolism , Red abalone -- Metabolism , Haliotis midae -- Physiology , Red abalone -- Physiology , Stable isotopes , Algae as feed
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/62314 , vital:28154
  • Description: The source of abalone for human consumption has shown a dramatic shift away from wild-capture fisheries in the last 30 years, with over 90% of global production now coming from aquaculture. Farmers initially relied on the natural food of abalone (macroalgae) as a culture feed, though in regions where macroalgae availability was limiting, the need to develop formulated feeds was evident. Extensive research effort has led to the development of a number of formulated feed products currently employed in the industry. These feeds, however, differ markedly from the mixed macroalgal diets that abalone have evolved to utilise, particularly in terms of protein content and carbohydrate structure. The degree to which the nutritional physiology of abalone responds to these novel formulated diets, with and without macroalgal supplementation, was investigated in the current study. A multifaceted approach, combining growth trials, stable isotope nutrient tracers and metabolic experiments, was employed to gain insight into the post-absorption dynamics and utilisation of dietary nutrients under varying dietary regimes of fresh macroalgae and formulated feed. Growth trials conducted with both Haliotis rufescens and H. midae showed significantly higher growth and protein utilisation efficiency for abalone fed macroalgal diets compared to formulated feeds. Furthermore, when formulated feeds were supplemented with macroalgae to form combination diets, growth and the utilization of protein was improved compared to the formulated-feed-only diet. The poor utilisation of protein by H. midae fed the formulated feed could be traced, using a method combining stable isotope bio-markers with a Bayesian mixing model (SIAR), to the low incorporation of the fishmeal component of protein in the diet. The marked postprandial drop in the O:N ratio on abalone fed formulated feeds indicate that the protein was being diverted into catabolic metabolic pathways. The metabolic cost of digestion, termed specific dynamic action (SDA), was negated as a factor in the improved growth of abalone fed macroalgal diets, with the SDA coefficient 2.1 times that observed for formulated feed. Furthermore, the postprandial haemolymph glucose concentration (HGC) in H. midae was elevated when fed formulated feed compared to macroalgae. The high levels of circulating glucose are likely a result of the structure the carbohydrate source in formulated feeds and stimulate the deposition of glycogen through the allosteric control of glycogen synthase. Formulated feeds produced higher cooked meat yields in canning simulation trials, suggesting that muscle glycogen content may indirectly play a role in increasing canning yields through the displacement of collagen. The results of these empirical studies are synthesised under key themes, discussed within the context of their potential commercial relevance and future research directions are highlighted.
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  • Date Issued: 2018

Aspects of the population ecology, habitat use and behaviour of the endangered Knysna seahorse (Hippocampus capensis Boulenger, 1900) in a residential marina estate, Knysna, South Africa: implications for conservation

  • Authors: Claassens, Louw
  • Date: 2018
  • Subjects: Endangered species -- South Africa -- Knysna , Sea horses -- Behavior -- South Africa -- Knysna , Sea horses -- Habitat -- South Africa -- Knysna , Sea horses -- Ecology -- South Africa -- Knysna
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/54789 , vital:26616
  • Description: The Knysna seahorse Hippocampus capensis is South Africa’s only endemic seahorse species, and is found in only three adjacent estuaries along the southern coast. The conservation of this endangered species is important on a national and international level. This study presents the first research on this species within the Knysna estuary since 2001 and specifically focuses on aspects of its ecology within a residential marina estate (Thesen Islands Marina). The physico-chemical and habitat features of the marina were described and the population ecology, habitat use, and behaviour of the Knysna seahorse were investigated. Physico-chemical conditions within the western section of the marina, characterised by high water current velocities, were similar to that of the adjacent estuary. The eastern section of the marina was characterised by lower water current velocities and higher turbidity. Four major habitat types were identified within the marina canals: (I) artificial Reno mattress (wire baskets filled with rocks); (II) Codium tenue beds; (III) mixed vegetation on sediment; and (IV) barren canal floor. Seahorse densities within the marina were significantly higher compared to densities found historically within the estuary. Highest seahorse densities were specifically found within the artificial Reno mattress structures and within the western section of the marina. Seahorse density varied spatially and temporally and the type of habitat was an important predictor for seahorse occurrence. An experimental investigation found that H. capensis chooses artificial Reno mattress habitat over Zostera capensis when given a choice. GoPro cameras were used successfully to investigate daytime seahorse behaviour within the Reno mattress habitat. Seahorses were more active during the morning, spent most of their time (> 80 %) feeding, and morning courting behaviour for this species were confirmed. However, during the summer holiday period (mid-December to mid-January) few seahorses were observed on camera, which suggests that the increase in motor boat activity and the related increase in noise had a negative effect on H. capensis feeding and courting behaviour. The marina development, and in particular the Reno mattresses, created a new habitat for this endangered species within the Knysna estuary. In addition to the protection and restoration of natural habitats in which H. capensis is found, the conservation potential of artificial structures such as Reno mattresses should be realised.
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  • Date Issued: 2018

Assessment of pharmaceutical equivalence of topical cream products containing hydrocortisone acetate using in vitro release testing (IVRT)

  • Authors: Mudyahoto, Nyengeterai Amanda
  • Date: 2018
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/63384 , vital:28404
  • Description: Expected release date-April 2020
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  • Date Issued: 2018

Assessment of pheromone specificity in Thaumatotibia leucotreta (Meyrick) populations with focus on pest monitoring and the regional rollout of the sterile insect technique in citrus

  • Authors: Joubert, Francois D
  • Date: 2018
  • Subjects: Cryptophlebia leucotreta , Pheromone traps , Citrus -- Diseases and pests -- South Africa , Cryptophlebia leucotreta -- Contol , Cryptophlebia leucotreta -- Biological control
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/60665 , vital:27812
  • Description: False codling moth (FCM), Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae) is considered the most important indigenous pest of citrus in southern Africa. It is recognized by several markets as a phytosanitary organism and the efficient control of this pest is now more important than ever. The pheromone communication between the male and female moths has been exploited in order to control FCM through the sterile insect technique (SIT). The sterilized males used for all SIT programmes across South Africa come from a colony that originates from wild material collected from the Citrusdal area of the Western Cape Province. The aim of this study was to determine if any differences in attractiveness of females to males exist between different geographical populations of FCM and if so what impact this would have on the male’s ability to locate females from other populations via the volatile sex pheromone released by the female. Laboratory trials with Y-tube olfactometers and flight tunnels tested the attraction of male moths to virgin females, but did not yield any consistent results. Field experiments were conducted with sterile male Citrusdal moths released and recaptured in yellow delta traps in two separate trials. For one trial, the traps were baited with live virgin females from five different geographical populations including Addo, Nelspruit, Marble Hall, Citrusdal and the Old colony, which is a mixture of several populations. For the other trial traps were baited with various synthetic pheromone blends including three regional blends which included South Africa, Ivory Coast and Malawi and three commercial blends including Pherolure, Isomate and Checkmate. For the virgin female trial the Citrusdal males showed a significant preference for females from their own population. There was also a significant difference in the recaptures from the different synthetic pheromones. The South African blend was the most attractive of all the regional and commercial blends. A cross-mating trial was also conducted under laboratory conditions in petri dishes with five different FCM populations including Citrusdal, Addo, Marble Hall, Nelspruit and Old (mixed origin). Females produced more eggs when mated with males from the same population for the Addo, Marble Hall, Nelspruit and Old (mixed origin) populations. The only case in which this was statistically significant was for the Marble Hall population. All the crosses produced viable eggs and the origin of the male or female did not influence egg hatch. The results from this study may lead to improvements in both the control and monitoring of FCM populations. The control methods include mating disruption, attract-and-kill and SIT. Tailoring these methods for a specific growing area with a pheromone blend originating from the area or releasing sterile moths from a colony that originates from the area may optimize the available monitoring and control options.
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  • Date Issued: 2018

Assessment of the human health implications of climate variability in East London, Eastern Cape, South Africa

  • Authors: Orimoloye, Israel Ropo https://orcid.org/0000-0001-5058-2799
  • Date: 2018
  • Subjects: Climatic changes http://id.loc.gov/authorities/subjects/sh85027037
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10353/19715 , vital:43171
  • Description: Impacts associated with climate variability and extreme heat are already obvious in varying degrees and expected to be disruptive in the near future across the globe especially in the urban regions. Urban areas have distinctive features that leave their residents and properties vulnerable to extreme climate events. Global temperatures continue to change, reaching new levels almost every year for the past two decades. However, even though the causes are debated it is evident that climate variability is real. Climate variability and disaster risk are threats to human health that adversely reinforce each other. Better knowledge on the association between climate change, variability and extreme weather-related illness is needed and can aid strategies to reduce vulnerabilities. The impacts of climate variability on the health of residents in East London (EL) area in the Eastern Cape Province, South Africa were explored through four interdependent research segments. The first section examined the climate variability and urban surface thermal characteristics implication on human health using Remote Sensing (RS) and Geographic Information System (GIS) techniques. Remote sensing was used to assess the Land Surface Temperature (LST) and estimated Radiation (R) of East London area from Landsat Thematic Mapper (TM) images for 1986, 1996, 2006 as well as from Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS) for 2016 spanning a period of 30 years. Rapid urbanization and land cover changes in this area have contributed significantly to this drastic change in the natural land surface characteristics (increased land surface temperature and surface solar radiation). For instance, vegetation cover declined by about 358.812km2 while built-up areas increased by 175.473km2 during this period which correlates with the area thermal characteristics changes. Radiation levels also increased over the years with values exceeding the global solar radiation index. Exposure to increased surface radiation poses risks of heat stroke, skin cancer and heart disease to the local population. Consequently, this study provides pertinent information on human health sustainability and epidemiological case management. The second part explored past temperature and humidity trends (1986-2016) and projects future trends (2017-2030). The historical data of meteorological variables were obtained from the archives of the South African Weather Service and analyzed using the ordinary least square regression model in GRETL (GNU Regression Econometric and Time-series Library) statistical software. This study discovered a local consistency between models and the observations add to existing knowledge and this is crucial in knowing the shifts in climatic change as well as recognizing variability and its conflicting effects on human health, environment, agriculture, ecological sustainability and socioeconomic status in the region. The third segment assessed the potential impacts of climate variability on health using existing heat indices during the study period. The results demonstrated that in East London from 1986 to 2016 during summer and autumn (December to May) of various years exceeded high heat index values. It is obvious that summer and autumn months are more vulnerable to heat extreme and humidex. The humidex and Heat Index (HI) increased annually by 0.03 percent and 0.9 percent respectively throughout the study period. The increment in the various indices showed highly significant ill-health and environmental impacts on humans especially with prolonged exposure. The last segment appraised the association between climatic elements and epidemiological incidences of the study area between 2012 and 2016. The epidemiology incidences data were obtained from the archives of the Cecilia Makiwane Hospital in East London area and National Tertiary Service Grant (NTSG) database for the period. The results have showed that there exists significant effects of climate variability on the health of East London residents and these have been identified to have negative impacts on health of the people in the area. This study also revealed noticeable impacts of extreme heat on human health and a positive correlation between meteorological components (HI and temperature) and epidemiological cases (cardiovascular, skin cancer and diarrhea) during the study period. , Thesis (PhD) (Geography) -- University of Fort Hare, 2018
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  • Date Issued: 2018

Assessment of the likely sensitivity to climate change for the key marine species in the southern Benguela system

  • Authors: Ortega-Cisneros, Kelly , Yokwana, Sibusiso , Sauer, Warwick H H , Cochrane, Kevern L , James, Nicola C , Potts, Warren M , Singh, L , Smale, Malcolm J , Wood, A , Pecl, Gretta T
  • Date: 2018
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/123211 , vital:35415 , https://doi.10.2989/1814232X.2018.1512526
  • Description: Climate change is altering many environmental parameters of coastal waters and open oceans, leading to substantial present-day and projected changes in the distribution, abundance and phenology of marine species. Attempts to assess how each species might respond to climate change can be data-, resource- and time-intensive. Moreover, in many regions of the world, including South Africa, species may be of vital socioeconomic or ecological importance though critical gaps may exist in our basic biological or ecological knowledge of the species. Here, we adapt and apply a trait-based sensitivity assessment for the key marine species in the southern Benguela system to estimate their potential relative sensitivity to the impacts of climate change. For our analysis, 40 priority species were selected based on their socioeconomic, ecological and/or recreational importance in the system. An extensive literature review and consultation with experts was undertaken concerning each species to gather information on their life history, habitat use and potential stressors. Fourteen attributes were used to estimate the selected species’ sensitivity and capacity to respond to climate change. A score ranging from low to high sensitivity was given for each attribute, based on the available information. Similarly, a score was assigned to the type and quality of information used to score each particular attribute, allowing an assessment of data-quality inputs for each species. The analysis identified the white steenbras Lithognathus lithognathus, soupfin shark Galeorhinus galeus, St Joseph Callorhinchus capensis and abalone Haliotis midae as potentially the most sensitive species to climate-change impacts in the southern Benguela system. There were data gaps for larval dispersal and settlement and metamorphosis cues for most of the evaluated species. Our results can be used by resource managers to determine the type of monitoring, intervention and planning that may be required to best respond to climate change, given the limited resources and significant knowledge gaps in many cases.
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  • Date Issued: 2018

Assessment of the long-term response to rehabilitation of two wetlands in KwaZulu-Natal, South Africa

  • Authors: Cowden, Craig
  • Date: 2018
  • Subjects: Wetlands -- South Africa -- KwaZulu-Natal Wetland restoration -- South Africa -- KwaZulu-Natal Wetland management -- South Africa -- KwaZulu-Natal Wetland conservation -- South Africa -- KwaZulu-Natal Wetland ecology -- South Africa -- KwaZulu-Natal Ecosystem management -- South Africa -- KwaZulu-Natal
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/60606 , vital:27802
  • Description: Assessing the outputs and outcomes of wetland rehabilitation activities is recognised by the 'Working for Wetlands' programme in South Africa as important, but to date has been limited. An assessment of the ecological outcomes and the structural outputs of the Working for Wetlands rehabilitation implemented in the Killarney and Kruisfontein wetlands, KwaZulu-Natal, in 2005 was undertaken. The assessment of outcomes included an evaluation of the changes in terms of ecological integrity and the supply of ecosystem services, using WET-Health and WET- EcoServices assessment techniques respectively, and vegetation composition. Improvements in hydrological and geomorphic integrity were recorded in both wetlands, resulting in improved ecosystem services delivery. However, investigation of vegetation composition using the Wetland Index Value and Floristic Quality Assessment Index showed that, seven years after rehabilitation, KiNamey's vegetation composition had improved, but Kruisfontein's vegetation was still largely dominated by pioneer species and appeared to be stable, but in a severely transformed state. The response of these wetlands has shown that sites for rehabilitation should be screened before work begins, and wetlands requiring intensive management of vegetation recovery should be assessed in terms of the objectives and the anticipated benefits of the project. The assessment of the outputs included an evaluation of structural integrity, survival and cost- effectiveness. Limited issues, mostly relating to deviations from the designs during construction, were identified with regards to the structural outputs at each of the wetlands. However, the spreader canals at both Killarney and Kruisfontein wetlands were not functioning as intended and concentrated flows from the spreader canals were evident in both wetlands. The use of spreader canals should therefore be carefully planned and implemented for future wetland rehabilitation projects. Consideration of ZAR per hectare equivalent re-instated/secured provided a useful initial means of determining the cost-effectiveness of the wetland rehabilitation. However, additional factors need to be considered, such as, the nature of the rehabilitation activities, the type and size of the problem being addressed, rehabilitation of priority wetlands, limitations imposed by funders, and risks that need to be addressed by the rehabilitation strategy. Furthermore, the evaluation of the Killarney and Kruisfontein wetlands highlighted the need to revise the Water Research Commission's Wetland Management Series, especially those documents or guidelines relating to rehabilitation planning (WET-RehabPlan), interventions (WET-RehabMethods), and monitoring and evaluation (WET-RehabEvaluate).
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  • Date Issued: 2018

Bacterial colonisation and degradation of geologically weathered and discard coal

  • Authors: Olawale, Jacob Taiwo
  • Date: 2018
  • Subjects: Coal mine waste , Coal -- Biodegradation , Coal mines and mining -- Environmental aspects , Land degradation , Electron microscopy , Extracellular polymeric substances , Flagella (Microbiology) , Fourier transform infrared spectroscopy , Microbiologically influenced corrosion
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/61625 , vital:28043
  • Description: Bacterial beneficiation of low-grade coal, coal discard, and waste has the potential to mitigate land degradation, water and soil pollution and, be a strategy for mining companies to responsibly extract and process coal with environmental sustainability. This study investigated the colonisation and biodegradation or depolymerisation of coal discard and geologically weathered coal by selected strains of bacteria, and an attempt has been made to describe the mechanisms associated with colonisation and biodegradation of this carbonaceous material. Ten bacterial strains, Bacillus strain ECCN 18b, Citrobacter strain ECCN 19b, Proteus strain ECCN 20b, Exiguobacterium strain ECCN 21b, Microbacterium strain ECCN 22b, Proteus strain ECCN 23b, Serratia strain ECCN 24b, Escherichia strain ECCN 25b, Bacillus strain ECCN 26b and Bacillus strain ECCN 41b, isolated from diesel-contaminated soil and coal slurry and identified using DNA sequencing, were rescreened and their coal biodegradation potential ranked. The ranking of the bacterial strains was undertaken using several indicators including; formation of brown halos on the plate culture (solid), change in colour intensity of the medium in liquid culture, change in culture media pH, and an increase in absorbance at 280nm and 450nm. Although, all the ten strains showed evidence of biodegradation of coal discard and geologically weathered coal based on the ranking employed, and the three strains considered the best candidates were Citrobacter strain ECCN 19b, Exiguobacterium strain ECCN 21b and Serratia strain ECCN 24b. The actions of the three bacterial strains were further studied and characterised in relation to coal degradation. Electron microscopy revealed that Citrobacter strain ECCN 19b, Exiguobacterium strain ECCN 21b and Serratia strain ECCN 24b attached to the surface of coal discard and geologically weathered coal by a process that appeared to involve extracellular polymeric substances (EPS), and flagella. The presence of flagella for Citrobacter strain ECCN 19b and Serratia strain ECCN 24b was confirmed by transmission electron microscopy. Bacterial degradation of coal discard and geologically weathered coal by these selected strains resulted in the release of soluble and insoluble products. Ultraviolet/ visible spectrophotometric (UV/VIS) analysis revealed that the soluble products resembled humic acid-like substances, which was confirmed following Fourier Transform Infrared (FTIR) spectroscopy. Analysis revealed that the coal-derived humic acid-like substances were similar to commercial humic acid extracted from bituminous coal. Elemental analysis of the insoluble product residue after bacterial biodegradation revealed the modification of the chemical compositions of the coal discard and geologically weathered coal substrates. Characterisation of the functional groups of the insoluble product using FTIR spectroscopy indicated changes, with the appearance of new peaks at 1737cm-1, 1366cm-1, 1228cm-1, and 1216cm-1 characteristic of aldehyde, ketones, carboxylic acids, esters, amines, and alkanes. Broad spectra regions of 3500 -3200cm-1, characteristic of alcohol and phenol, were also observed. Together, these results were taken as evidence for increased oxidation of the coal substrates, presumably as a consequence of bacterial catalysed biodegradation of coal discard and geologically weathered coal. During bacterial degradation of coal discard and geologically weathered coal, strains produced extracellular protein, which was detected and further investigated using sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS- PAGE). At least three protein bands with molecular mass 53 kDa, 72 kDa, and 82 kDa were common to the three bacterial strains. Following ammonium sulphate precipitation and gel filtration chromatography, additional bands with molecular mass 16 kDa, 33 kDa, 37 kDa, and 43 kDa were detected. An extracellular laccase activity was detected in cultures of Exiguobacterium strain ECCN 21b and Serratia strain ECCN 24b. Cytochrome P450 activity was detected in all the bacterial strains in the presence of both coal discard and geologically weathered coal. This is the first time that cytochrome P450 activity has been reported following exposure of these three bacterial strains to a coal substrate. Overall, this research has successfully demonstrated the partial degradation of coal discard and geologically weathered coal by Citrobacter strain ECCN 19b, Exiguobacterium strain ECCN 21b and Serratia strain ECCN 24b and the release of humic acid-like substances. Thus, the biodegradation process involved adherence to and growth of the bacteria on the surface of coal substrate and appeared to require the formation of alkaline substances and the combined activities of extracellular LAC and cytochrome P450. Since bacterial degradation of low-grade coal and discard appears to be viable, the bacteria isolated in this study can potentially be used either for conversion of discard into valuable chemicals or to mitigate the deleterious effects of stockpiled coal discard on the environment.
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  • Date Issued: 2018

Baculovirus synergism: investigating mixed alphabaculovirus and betabaculovirus infections in the false codling moth, thaumatotibia leucotreta, for improved pest control

  • Authors: Jukes, Michael David
  • Date: 2018
  • Subjects: Baculoviruses , Cryptophlebia leucotreta -- Biological control , Citrus -- Diseases and pests -- South Africa , Pests -- Integrated control , Nucleopolyhedroviruses , Natural pesticides , Cryptophlebia leucotreta granulovirus (CrleGV)
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/61797 , vital:28061
  • Description: Baculovirus based biopesticides are an effective and environmentally friendly approach for the control of agriculturally important insect pests. The false codling moth (FCM), Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae), is indigenous to southern Africa and is a major pest of citrus crops. This moth poses a serious risk to export of fruit to foreign markets and the control of this pest is therefore imperative. The Cryptophlebia leucotreta granulovirus (CrleGV) has been commercially formulated into the products Cryptogran™ and Cryptex®. These products have been used successfully for over a decade as part of a rigorous integrated pest management (IPM) programme to control T. leucotreta in South Africa. There is however, a continuous need to improve this programme while also addressing new challenges as they arise. An example of a rising concern is the possibility of resistance developing towards CrleGV. This was seen in Europe with field populations of the codling moth, Cydia pomonella (Linnaeus) (Lepidoptera: Tortricidae), which developed resistance to the Mexican isolate of the Cydia pomonella granulovirus (CpGV-M). To prevent such a scenario occurring in South Africa, there is a need to improve existing methods of control. For example, additional baculovirus variants can be isolated and characterised for determining virulence, which can then be developed as new biopesticides. Additionally, the potential for synergistic effects between different baculoviruses infecting the same host can be explored for improved virulence. A novel nucleopolyhedrovirus was recently identified in T. leucotreta larval homogenates which were also infected with CrleGV. This provided unique opportunities for continued research and development. In this study, a method using C. pomonella larvae, which can be infected by the NPV but not by CrleGV, was developed to separate the NPV from GV-NPV mixtures in an in vivo system. Examination of NPV OBs by transmission electron microscopy showed purified occlusion bodies with a single nucleopolyhedrovirus morphology (SNPV). Genetic characterisation identified the novel NPV as Cryptophlebia peltastica nucleopolyhedrovirus (CrpeNPV), which was recently isolated from the litchi moth, Cryptophlebia peltastica (Meyrick) (Lepidoptera: Tortricidae). To begin examining the potential for synergism between the two viruses, a multiplex PCR assay was developed to accurately detect CrleGV and/or CrpeNPV in mixed infections. This assay was applied to various samples to screen for the presence of CrpeNPV and CrleGV. Additionally, a validation experiment was performed using different combinations of CrpeNPV and/or CrleGV to evaluate the effectiveness of the mPCR assay. The results obtained indicated a high degree of specificity with the correct amplicons generated for each test sample. The biological activity of CrpeNPV and CrleGV were evaluated using surface dose bioassays, both individually and in various combinations, against T. leucotreta neonate larvae in a laboratory setting. A synergistic effect was recorded in the combination treatments, showing improved virulence when compared against each virus in isolation. The LC90 for CrpeNPV and CrleGV when applied alone against T. leucotreta was calculated to be 2.75*106 and 3.00*106 OBs.ml"1 respectively. These values decreased to 1.07*106 and 7.18*105 OBs.ml"1 when combinations of CrleGV and CrpeNPV were applied at ratios of 3:1 and 1:3 respectively. These results indicate a potential for developing improved biopesticides for the control of T. leucotreta in the field. To better understand the interactions between CrleGV and CrpeNPV, experiments involving the serial passage of these viruses through T. leucotreta larvae were performed. This was done using each virus in isolation as well as both viruses in different combinations. Genomic DNA was extracted from recovered occlusion bodies after each passage and examined by multiplex and quantitative PCR. This analysis enabled the detection of each virus present throughout this assay, as well as recording shifts in the ratio of CrleGV and CrpeNPV at each passage. CrleGV rapidly became the dominant virus in all treatments, indicating a potentially antagonistic interaction during serial passage. Additionally, CrpeNPV and CrleGV were detected in treatments which were not originally inoculated with one or either virus, indicating potential covert infections in T. leucotreta. Occlusion bodies recovered from the final passage were used to inoculate C. pomonella larvae to isolate CrpeNPV from CrleGV. Genomic DNA was extracted from these CrpeNPV OBs and examined by restriction endonuclease assays and next generation sequencing. This enabled the identification of potential recombination events which may have occurred during the dual GV and NPV infections throughout the passage assay. No recombination events were identified in the CrpeNPV genome sequences assembled from virus collected at the end of the passage assay. Lastly, the efficacy of CrpeNPV and CrleGV, both alone and in various combinations, was evaluated in the field. In two separate trials conducted on citrus, unfavorable field conditions resulted in no significant reduction in fruit infestation for both the virus and chemical treatments. While not statistically significant, virus treatments were recorded to have the lowest levels of fruit infestation with a measured reduction of up to 64 %. This study is the first to report a synergistic effect between CrleGV and CrpeNPV in T. leucotreta. The discovery of beneficial interactions creates an opportunity for the development of novel biopesticides for improved control of this pest in South Africa.
  • Full Text:
  • Date Issued: 2018
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