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Investigating thermoregulatory responses of rhabdomys pumilio at high wet-bulb temperatures
Get PDFAs the Anthropocene continues to be characterised by ever rising temperature highs, increasingly sporadic and extreme climatic events, and their accompanying mass mortality events, climate scientists now warn that the continued climate destabilisation may for the first time in recorded history prevent terrestrial homeothermic endotherms from being able to thermoregulate. Having evolved to maintain body temperatures (Tbs) well above their ambient (Ta) conditions, these endotherms have evolved a suite of adaptations to a colder environment to allow for homeothermic thermoregulation to occur. However, by the same vein, having evolved in a colder climate to stay warm also has led to a reduced capacity to prevent heat stress when temperature conditions are elevated. In absence of behavioural counter measures, the only physiological means available to thermoregulation to prevent such heat stress is that of evaporative water loss (EWL). If still inefficient, the endotherm will risk becoming hyperthermic. Literature has established that excessive heat exposure or reduced evaporative cooling capacities strain or retard thermoregulatory processes. If an endotherm experiences severe heat exposure, the rate at which passive heating is experienced will increase. Should an endotherm be in a humid environment, evaporative cooling efficiency is reduced. As a result, these two abiotic factors are therefore known to contribute towards heat storage, and therefore thermal stress. However, should both factors occur in the same environment, the heat stress effects are compounded, creating an environment dangerous for thermoregulating endotherms. For this reason, authors have emphasised that future wet-bulb (Tw) conditions may pose a penultimate threat to thermoregulating endotherms. Being a measure of coldest temperature attainable as a result of evaporative cooling, Tw has been proposed to represent a lower temperature thermal limit to endothermic thermoregulation. Once reaching a 2°C differential below an endotherms Tb (Tb – Tw = 2˚C), Tw is believed to impede the evaporative cooling process and, consequentially, commit endotherms to becoming hyperthermic. Considering that most mammals defend constant Tbs within the range of predicted Tw maxima increases that future Tw conditions may pose a significant threat to mammalian thermoregulation. However, to date, despite being well supported in the literature, ii empirical investigations into how extreme Tw conditions will affect endothermic thermoregulation are scant. Therefore, understanding of the proposed inhibitory nature of extreme Tw conditions is lacking. Considering that such conditions are to have a profound effect of endothermic survival, this dearth in understanding could prove fatal. As such, this thesis sought to provide evidence on how extreme Tw conditions may affect thermoregulatory processes in homeothermic endotherms.Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 202
The development of a framework to assess the key factors that may impact the future price of weaners (cattle) in South Africa
Get PDFThe global livestock production systems are changing due to a variety of factors, which have an impact on the price of red meat. The supply of weaners (cattle) is affected by a number of factors including the type of production system, feed costs, diseases and weather conditions. The demand for weaners (cattle) is affected by factors including, amongst various others, consumers’ perception of quality, value for money, health benefits, economic profile, expandable income, urbanisation and socio-economic factors. These factors are complex and interrelated in terms of their potential impact on weaner prices and have a significant influence on production and investment decisions in the industry. This study used quantitative research to investigate the relationship between the factors influencing the price of weaners (cattle). For the purpose of data collection, a closed ended questionnaire was distributed to the respondents. This study was done using non-probability sampling. The sampling method used in this study is referred to as snowball sampling, which is a process using networks. The data was analysed to conclude which factors are impacting the price of weaners (cattle) the most. The results show that the supply factors of weaners are experiencing increasing pressure with changing weather conditions, input costs and animal diseases. The demand factors such as quality, currency and population are increasing the complexity, which implies the market is changing from a producer orientated market to a consumer orientated market. The study provides a framework to predict future prices of weaners, which is expected to influence both production and investment decisions which contribute toward the sustainability of the industry. The study recommends that the South African weaner (cattle) industry has experienced a significant increase in demand, both locally and globally. Meeting this growing demand has its own complexity that limits weaner farmers’ supply of weaners. The market is changing from a producer orientated to a consumer orientated perspective, which will force the supply chain to keep up with the changing consumer factors.Thesis (MA) -- Faculty of business and economic sciences, 202
An evaluation of the effectiveness of area-based conservation intervention in avoiding biodiversity loss in South Africa
No full textHabitat degradation, livestock farming, crop cultivation, rangeland overutilization and veld mismanagement are among the factors causing biodiversity loss worldwide. Rangelands in arid and semi-arid environments are no exception, as they are under stress from conversion into cropland and pressure from livestock farming. In these arid areas, rainfall is unpredictable and plant recruitment levels low, resulting in veld rehabilitation being a potentially expensive and time-consuming undertaking for landowners. Landowners implement different rehabilitation methods to increase overall vegetation cover and prevent further soil and vegetation degradation. These rehabilitation methods may include the creation of micro-catchments, mulching, brushpacking, ripping, geotextiles, stone cobbling and erosion control fences, individually or in combination with the addition of reseeding, replanting, and use of manure or fertilizer to supplement land rehabilitation. This study investigated the significance of three rehabilitation methods (hollows, brush packing and a combination of these two methods) on water infiltration rates, soil moisture content, and vegetation canopy cover with associated growth form canopy cover over a period of 17 months (March 2021 to August 2022). This study showed that rehabilitation methods implemented had no significant impact on water infiltration rates and vegetation canopy cover. However, rehabilitation methods had a significant impact on soil moisture content. The use of a hollows is recommended when attempting to increase the soil moisture content percentage when performing rehabilitation. Overall vegetation canopy cover is influenced more by seasonal changes than by the rehabilitation methods implemented. This study indicated that the creation of micro-catchments is an effective rehabilitation method to use in an arid area, as it promotes vegetation establishment and growth.Thesis (MSc) -- Faculty of Science, School of Natural Resource Science and Management , 202
Assessing the Role of Women on Small-Scale Agribusiness at Wincanton Estate in Kariega, South Africa
Get PDFAgricultural development is a prerequisite for most economies to grow. Agricultural activities are key to food security and sustaining livelihoods globally. Within the African continent, more women are employed in agriculture and agribusiness activities than other sectors. As main contributors to the labour force in the agricultural sector, women get involved in many agricultural and agribusiness activities to sustain their families. With over 60% of women in Sub–Saharan Africa involved in agriculture, there is need to explore and assess the role they play in promoting agribusiness with special focus on Kariega, in South Africa. The identified participants in the study, as self-employed farmers, participate in agribusiness, thereby creating employment opportunities whilst generating personal incomes. Several benefits to female involvement in agribusiness were identified, including the ability to sustain families, stable cash flow, and empowerment. Several challenges were identified, including adequate capital, inaccessibility to private land, droughts, water scarcity, climate change effects and stigmatisation. Through a feminist qualitative methodology, the study utilised semi- structured interviews to collect data from 10 women involved in agribusiness around Kariega, Nelson Mandela Bay. Themes from the findings are analysed to highlight the important role played by women toward agribusiness, their achievements, government and private sector role and the hinderances still faced by these women in agricultural cooperatives. Discussion from the analysis included a framework of recommendations, for policy makers, development practitioners and future researchers. The study found that all stakeholders involved in the agricultural sector should work together for sustainable agricultural development and sustainable development goals to be achieved. Sustainability among women farmers can be achieved by (a) Increasing government intervention and support (b) Climate smart agriculture practices (c) Overcoming stigmatisation (d) Encouraging and involving the youth (e) Diversification and integration of farm businesses and (f) Using contract farming.Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 202
Technology acceptance model perceptions of operational staff on the implementation of advanced radiography equipment
Get PDFThroughout the recent history of South Africa, the increasing requirements from state and private sector healthcare institutions have relied heavily upon medical imaging technologies for the purposes of improved patient healthcare and service quality standards. Developments in this field of healthcare have seen many interesting and challenging operational changes: from the first implementation and use of X-ray equipment demonstrated in Krugersdorp in 1899; to the current advanced digital systems found in the medical imaging services sector of healthcare. This research study measured the medical imaging operational staff perceptions about new advanced medical imaging equipment and technologies. The theory crossed the academic disciplines through a quantitative survey about technology, operations management and healthcare. Together with staff perceptions about future medical imaging technologies’ usefulness and ease of use, the findings may impact their daily operations within a conducive technology acceptance management paradigm.Thesis (MA) -- Faculty of Faculty of Business and Economic Sciences, 202
The protection of the primary residence of a debtor in debt enforcement and insolvency
Get PDFMany people, particularly in South Africa, turn to borrowing money to pay for their everyday expenses. It is also generally acknowledged that mortgage financing is crucial to our economy and that it should remain readily available to people with a variety of incomes. Banks, and other secured lenders need confirmations that their security is reasonably safe to ensure that this remains the case. A debtor with immovable property is preferred because should the debtor fail to comply with his contractual obligations and there is no movable property to attach, the creditor will proceed to attach the immovable property of that debtor. In South Africa the law relating to debt enforcement proceedings and the provisions of the Insolvent Act allow for the attachment of the primary residence of a debtor/insolvent. There is a judicial process that is followed for the attachment of the house through debt enforcement. During insolvency the debtor is divested of his property immediately after granting of the sequestration order. These proceedings go as far as stripping a poor person of even a RDP house that they obtained through the Housing Act, a programme designed to provide housing to the poor. This study examines the relationship between the right to access housing and the right to human dignity, considering South Africa's past, the idea of transformative constitutionalism, and the argument that the 1996 South African Constitution's transformative vision is one that is committed to addressing socio-economic inequality. The legal position in South Africa is compared to that of the United Kingdom and the recommendation made by the study is that a stay in proceedings during insolvency for a defined period before the home of the insolvent is sold in execution would help advance the goals of the government and protect rights of those people whose estates are declared insolvent. Further, a complete exclusion of RDP houses from debt enforcement proceeding and insolvency, is suggested. The rights to equality and the right to property are considered in favour of the creditor. All rights are considered against the limitation clause, and it is submitted that a stay in sale of the primary household for a specific period during insolvency proceedings and the complete exclusion of RDP homes from sales in execution and sales during sequestration would not amount to an unjustifiable limitation of the creditor’s rights.Thesis (LLM) -- Faculty of Law, School of School of Private Law, 202
Challenges and opportunities of coastal and marine tourism in Swartkops river Estuary
Get PDFThis study's goal was to pinpoint the challenges and untapped opportunities associated with Coastal and Marine Tourism (CMT) in the Swartkops River Estuary (SRE). CMT has become the biggest segment of the travel industry. Moreover, this form of alternative tourism is the most significant and fastest developing economic activity in the ocean. The objectives of this study were to identify the challenges that hinder the development of CMT in SRE, to determine opportunities for CMT in SRE, to evaluate NMBM’s efforts in creating and sustaining CMT in SRE and to evaluate the status of CMT in SRE in terms of CMT related development. This study fit within the interprevist paradigm and made use of a qualitative research approach and design as well as inductive reasoning. The qualitative research design consisted of data being collected through document and content analysis. Data was analysed using data analysis process of Miles and Herman (1994) as well as the coding and developing of specific themes that emerged from the data. The data in this phase was presented both in narrative format and tables. The document analysis used in this study was established based on the objectives of this study. The findings of this study revealed that key challenges that hinder the growth of CMT in Swartkops River Estuary are environmental impacts that include pollution, over enrichment, inappropriate development, overfishing, destruction of mudflats, limited freshwater inflow, destruction of vegetation and climate change. The findings also revealed that there are opportunities for CMT in SRE such as promoting SRE as a popular ecotourism destination by developing ecotourism nodes. These include environmental education at the Aloes Nature Reserve's and the Swartkops Estuary south-east section, sustainable ecolodges and conference centres. The study recommends that the Nelson Mandela Bay Municipality should organize educational programmes to educate local people about the significance of conserving and safeguarding the environment for future generations. These findings also posed certain challenges linked to those identified in the analysis.Thesis (MPhil) -- Faculty of Business and Economic Sciences, School of Economics, Development & Tourism, 202
The effect of Cannabis extract on the morphological and metabolic characteristics of various fat depots in diet-induced Obese and STZ-induced male wistar rats
Get PDFTo investigate the potential anti-diabetic/obesity properties of oral cannabis administration in an obese and streptozotocin (STZ)-induced diabetic rat model, as well as an obese rat model, and to determine the mechanism of action, with a focus on the peritoneal and intramuscular fat depots. Experimental Design: Obese and STZ-induced diabetic rats were allocated a high fat diet (HFD) and intraperitoneally injected with STZ to mimic an obese and diabetic state. The rats were then orally administered cannabis extract (CE) of 1.25, 2.5 and 5.0 mg/kg body weight (relative to tetrahydrocannabinol (THC) content) or metformin as a positive control. For the obese rat model, the rats were allocated either a high carbohydrate diet (HCD) or high fat diet (HFD) and orally administered with cannabis extract of 1.25 mg/kg body weight (relative to THC content). Weight, blood and insulin-resistant parameters of the rats were monitored. The mitochondrial to genomic DNA ratio (MT:18S DNA), average adipocyte area of the various adipose tissues, citrate synthase and carnitine palmitoyltransferase 1 (CPT1) enzyme activities of the peritoneal and intramuscular fat were measured. Gene expression levels of uncoupling protein 1 (UCP1), cell-death inducing DNA fragmentation factor alpha like effector-a (Cidea), perilipin, hormone-sensitive lipase (HSL) and mitochondrial transcription factor A (TFAM) were measured in peritoneal fat, intramuscular fat and brown adipose tissue (BAT). Main Findings: Obese and STZ-induced diabetic rat model: Due to the biphasic nature of cannabinoids, cannabis dosage plays an important role in the observed effects. CE1.25 was the only cannabis treatment effective in improving the insulinresistant parameters of the rats unlike the other higher cannabis concentrations (CE2.5 and CE5.0). In the peritoneal fat, CE1.25 increased MT:18S DNA, increased citrate synthase activity, and decreased the average adipocyte area when compared to the STZ group. CE1.25 also induced fat beigeing by upregulating gene expression levels of UCP1 and Cidea. XIX Furthermore, an increase in gene expression levels of perilipin, HSL, and TFAM showed increased fat mobilization and metabolic activity. In the intramuscular fat, CE1.25 also reduced the average adipocytes area. However, a different mechanism of action was observed where CE1.25 did not induce fat beigeing, but instead increased both citrate synthase and CPT1 enzyme activities and gene expression levels of HSL, thereby indicating increased fat oxidation and mitochondrial activity.Thesis (PhD) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 202
The environmental impacts associated with offshore oil and gas exploration in Namibia's emerging blue economy policy
Get PDFOil and gas exploration must have firm and clear environmental protection legislation as a blue economy industry. The Ministry of Mines and Energy regulates offshore oil and gas explorations in Namibia, and this is complemented by the Ministry of Fisheries and Marine Resources, the Ministry of Environment Forestry and Tourism, and the Ministry of Works and Transport to ensure that associated environmental impacts are minimised or mitigated. They govern the environmental protection of offshore oil and gas exploration with one regulation, seven policies, and ten legislations. While these regulations are individually good as they show consideration for most environmental impacts associated with oil and gas explorations, implementation remains challenging due to fragmentation in mandates among the key ministries. A qualitative research approach was used to meet the project objectives. Legislation documents, policy documents, the blue economy, and oil and gas literature were reviewed and interpreted, and they thus provided the content that was analysed to answer the research questions. Which aimed at examining the environmental protection regulations addressing environmental impacts associated with offshore oil and gas exploration in Namibia. Two main environmental impacts were identified, oil spills and underwater noise pollution. While there is adequate consideration for oil spills in the Namibian legislation, there is no specific consideration for underwater noise pollution, a significant environmental impact from offshore upstream activities. Recommendations were made to improve the implementation of environmental protection measures and develop national legislation for mitigating underwater noise pollution. Involving locals (Namibians) in emerging industries, whether marine or not, is critical in identifying environmental threats and socio-economic opportunities, thereby making for an inclusive sector as the blue economy concept intended.Thesis (MPhil) -- Faculty of Business and Economic Sciences, School of Economics, Development and Tourism, 202
The state of professional compliance during project implementation in a selected construction industry in Gauteng
Get PDFPublic sector construction projects in South Africa are not always implemented successfully as a result of professional non-compliance in the construction industry by professionals entrusted with the responsibility to deliver construction projects. Professionals in the construction industry registered with the built environment regulatory bodies must demonstrate professionalism in terms of competency and conduct when carrying out their professional duties as prescribed by the relevant regulatory bodies they belong to. This study utilised a qualitative case study to investigate the state of professional compliance during project implementation in a selected construction industry in Gauteng. A purposive sampling method was adopted to select participants with at least two years’ experience in managing public sector construction project implementation in Gauteng, resulting in 11 participants in the study. Semi-structured interview questions were designed and put to the participants during telephonic interviews. The research findings suggest that professional competency and conduct compliance requirements which contribute to effective project implementation include a relevant qualification as an initial step to become professional in the construction industry, followed by work experience, knowledge and registration with relevant regulatory and professional bodies which also require registered professionals to abide by their ethics and code of conduct. The findings suggest that the forms of non-compliance in terms of professional competency and conduct affecting effective project implementation were the result of a lack of experience or knowledge of construction professionals in relation to the project, poor quality of work and professionals’ neglect of duties. The perceived types of professional non-compliance affecting effective project implementation in the construction industry revealed by the findings included amongst others, breach of obligations, corruption, bribery and fraud, conflict of interest and carelessness; and factors of professional non-compliance such as high discounts, community disruptions, junior staff not been monitored, political relations and competition.Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 202