Evaluation of incidence of Mycobacterium tuberculosis complex associated with soil, hayfeed and water in three Agricultural facilities in Amathole District Municipality in the Eastern Cape Province, South Africa
- Authors: Ntloko, Athini
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: http://hdl.handle.net/10353/756 , vital:26494
- Description: Mycobacterium bovis and other species of Mycobacterium tuberculosis complex (MTBC) can result to a zoonotic infection known as Bovine tuberculosis (bTB). MTBC has members that may contaminate an extensive range of hosts, including wildlife. Diverse wild species are known to cause disease in domestic livestock and are acknowledged as TB reservoirs. It has been a main study worldwide to deliberate on bTB risk factors as a result some studies focused on particular parts of risk factors such as wildlife and herd management. The objectives of this study were to design questionnaires from commercial farms and smallholding farms; isolate and identify MTBC from collected samples using culture and PCR assays recovered from Fort Hare, Middledrift and Seven star dairy farms; and assessing genotypic drug resistance through detection of mutations conferring resistance to INH and RMP associated with first line treatment for MTBC infection. Questionnaires were administered to thirty (30) smallholding farm owners in the two villages (kwaMasele and Qungqwala) and three (3) three commercial farms ( Fort Hare dairy farm, Middledrift dairy farm and Seven star dairy farm). Detection of M. tuberculosis complex was achieved by Polymerase Chain Reaction using primers for IS6110; whereas a genotypic drug resistance mutation was detected using Genotype MTBDRplus assays. Nine percent (9%) of respondents had more than 40 cows in their herd, while 60% reported between 10 and 20 cows in their herd. Relationship between farm size and vaccination for TB differed from forty one percent (41%) being the highest to the least five percent (5%). The highest number of respondents who knew about relationship between TB cases and cattle location was ninety one percent (91%). Approximately fifty one percent (51%) of respondents had knowledge about wild life access to the farms. Relationship between import of cattle and farm size ranged from nine percent (9%) to thirty five percent (35%). Cattle sickness in relation to farm size differed from forty three (43%) being the highest to the least three percent (3%); while thirty three percent (33%) of respondents had knowledge about health management. Respondents with knowledge about the occurrence of TB infections in farms were forty eight percent (48%). The frequency of DNA isolation from samples ranged from the highest forty five percent (45%) from water to the least twenty two percent (22%) from soil. Fort Hare dairy farm had the highest number of positive samples forty four percent (44%) from water samples; whereas Middledrift dairy farm had the lowest positive from water, seventeen percent (17%). Twelve (22%) out of 55 isolates showed resistance to INH and RMP that is, multi-drug resistance (MDR) and nine percent (9%) were sensitive to either INH or RMP. The mutations at rpoB gene differed from 58% being the highest to the least (23%). Fifty seven percent (57%) of samples showed a S315T1 mutation while only 14% possessed a S531L in the katG gene. The highest inhA mutations were detected in T8A (80%) eighty percent and the least was observed in A16G (17%). The results of this study reveals that risk factors for bTB in cattle and dairy farm workers is a serious issue abound in the Eastern Cape of South Africa; with the possibility of widespread dissemination of multidrug resistant determinants in MTBC from the environment.
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- Date Issued: 2015
Experiences of HIV positive clients defaulting isoniazid preventive therapy (IPT) in King Williams Town area under the Buffalo City Municipality in the Eastern Cape Province
- Authors: Williams, Nelisa Colleen
- Date: 2015
- Subjects: AIDS (Disease) -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Community Nursing Science)
- Identifier: vital:11923 , http://hdl.handle.net/10353/d1020177 , AIDS (Disease) -- South Africa -- Eastern Cape
- Description: This qualitative study using a phenomenological design, aimed at exploring and describing and exploring the experiences of HIV positive clients defaulting Isoniazid Preventive Therapy services in the Bhisho Primary Health Care Services. The emphasis was on the factors leading clients to default. An in- depth unstructured face to face interviews were done on 14 participants from 4 clinics or facilities under Bhisho Primary Health Care Services. From the respondents’ responses it can be noted that work and family related issues, ignorance of patients, side effects, and negligence of nurses and denial of HIV status were identified as reasons for defaulting. Having knowledge about the treatment and health providers’ attitudes to patients also played a role in patients defaulting their treatment.Many suggestions were then put forward by the respondents to curb defaulting among patients. These included the use of text message reminders, not to discrimination HIV patients because of their status, to use consulting rooms for privacy and also nurses and caregivers to control their attitudes when dealing with patients.
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- Date Issued: 2015
Exploring user experience (UX) factors For ICTD services
- Authors: Nyambi, Pride Bongiwe
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11400 , http://hdl.handle.net/10353/d1020164
- Description: Consistent with global entities such as the United Nations- through the World Summit of the Information Society (WSIS), introduction of Information and Communication Technology (ICT) for human development has seen the introduction of ICT-based services aimed at facilitating socio-economic development of marginalized communities. The use of ICTs has always solicited the concept of Human Computer Interaction (HCI), which involves the methods which humans interact with technology. The types of User Interfaces (UIs) and interaction techniques that people use to interact with ICTs affects the way they perceive technology and eventually, their acceptance of the technology. Current ICT systems still haven‟t adopted the concept of placing the user at the core of the interaction. Users are still required to adapt themselves to the interface‟s characteristics; which limits the number of people who can use the system due to inabilities to adapt to the interface. As a result, the information embedded in these technologies is still inaccessible and useless to Marginalized Rural Area (MRA) users. Such usability challenges can be mitigated against and avoided by matching UI components with the users‟ mental models, language, preferences, needs and other socio-cultural artefacts. In this research, literature in Human-Computer Interaction (HCI) is reviewed with emphasis on the usability and User Experience (UX) during user interaction with ICTs using various modes of interactions. HCI emphasizes the need for systems to take account of user‟s characteristics such as their abilities, needs, socio-cultural experiences, behaviours and interests. In efforts to meet the requirement of UX, the user, system and the context of use, need to be evaluated, taking into consideration that changing one entity modifies the UX. This will be achieved by persona profiling to determine the key characteristics of the user communities, clustered according to the key UX attributes. Subsequently, through detailed usability evaluations, including the use of System Usability Scale (SUS) to determine user satisfaction with various UI components/techniques per identified persona- thus providing and persona mapping for usability of Information and Communication Technology for Development (ICTD) services. The results from this research are reflective of the importance of creating personas for usability testing. Some of the personas do not have a problem with interacting with most of the interfaces but their choice of interface comes from a preference point of view. For some personas, their skills and level of experience with ICTs motivates their choice of interface. The common UI component that users from across the spectrum appreciate is UI consistency which makes interaction easier and more natural. Common obstacles with current User Interfaces (UIs) that inhibit users from MRAs include the hefty use of text in interfaces, unintuitive navigation structures and the use of a foreign language. Differences in UIs from different application developers present an inconsistency which challenges the users from rural areas. These differences include the layout, the text entry methods and the form of output produced. A solution to this has been identified from the usability test as the use of speech-enabled interfaces in a language that can be understood by the target audience. In addition, through literature study it has been found that UX of interfaces can be improved by the use of less textual or text-free interfaces. Based on literature, users from MRAs can benefit from using hand-writing based UIs for text-based entry which mimics pen and paper environment for literate users who have experience with writing. Finally, the use of numbered options can assist illiterate users in tasks that requires users to choose options and for navigation. Therefore, consistency in UIs designed to be used by MRA users can improve usability of these interfaces and thus, improving the overall UX.
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- Date Issued: 2015
Factors affecting participation rates in farming in the rural areas of South Africa: case of Amathole District Municipality
- Authors: Zamxaka, Xolisa
- Date: 2015
- Subjects: Agricultural systems -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11233 , http://hdl.handle.net/10353/d1021291 , Agricultural systems -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape
- Description: South Africa and the rest of developing countries are faced with poverty and poor rural development. Rural participation in agricultural activities is one of the components that can be used to address the poverty challenge facing the people residing in rural areas. The broad objective of this research is to determine factors affecting participation rate in farming in the rural areas of Amathole District Municipality of Eastern Cape. In this study stratified random sampling method was applied in order to choose a sample out of 30 households that were interviewed 13 people belonged to Participants and 17 people belonged to non-Participants. The results from this study show that women participate a lot in farming activities. The multiple regression model was used to test the participation rates of the people in Amathole region specifically Phumlani area. A number of variables were considered in this study to assess the impact of different variables on participation in farming activities. The results showed that about 57% of the respondents are not participating in farming while 43% of the respondents participate. The farming participants that were interviewed all claim that there is a lack in farming support in the area. When there is no support of any kind, rural people would not be motivated to start development projects on their own. Consequently, this lack of farming support in the Phumlani area may have an influence on the number of farming participants. Therefore, the lack of support in the area may serve as a motivation for non-participants not to be influenced to farm. Rural farming needs to be promoted amongst the youth so as to protect and sustain agricultural growth in rural areas. The study has discovered that the youth of Phumlani is not actively involved in farming activities. Government can provide community members with farming resources so as to promote farming in the area. It would be wiser for the government to provide physical farming resources and implements rather than cash grants.
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- Date Issued: 2015
Geological and geophysical investigation of the South Eastern Karoo Basin, South Africa
- Authors: Baiyegunhi, Christopher
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Geology)
- Identifier: vital:11532 , http://hdl.handle.net/10353/d1021280
- Description: Geological and geophysical methods were used to investigate the southeastern Karoo Basin of South Africa in an area extending from longitudes 24 o E to 29o E and latitudes 32o S to 35o S. This was undertaken in order to reveal geologic structures, isochore thicknesses of the geologic sequence and their variations across the study area, proffer the possible provenance of the sediments and assess the potential of oil and gas accumulation. The methodology used includes field investigation, rock sampling, preparation of thin sections, petrographic studies, X-ray diffraction analysis, density measurements, porosity calculations, extraction of elevation data from Google Earth, 2½ D gravity profile modelling, generating of isochore (true vertical) thicknesses and depositional surfaces maps from the models, PetroMod 1D modelling and qualitative interpretation of magnetic, gravity and radiometric maps.Petrographic study was carried out on twenty six thin sections of rocks from the eleven geologic formations that cover the study area. Petrographic studies on the diamictite of the Dwyka Group shows abundance of monocrystalline quartz, granite and quartzite components in the breccias which possibly indicate the existence of granitic and metamorphic rocks in the source areas. The sandstones of the Ecca and Beaufort Groups are immature, greywacke and the heavy mineral assemblages signify that the minerals are of granitic, volcanic and metamorphic origin. The magnetic maps show two main magnetic anomalies, a major one trending in a northeast to southwest direction which is part of the Beattie magnetic anomaly and another that is a “bean-shaped” anomaly. The radially averaged power spectrum shows two depths to magnetic sources. The first depth is about 0.6 km which is the average depth to the top of the shallow sources, while the average depth to the top of the deep sources is about 15 km. The shallow sources are connected to magnetic minerals within the Beaufort Group while deep magnetic sources were inferred to be in the basement. The gamma ray spectrometric map shows areas with relatively high gamma radiation count. The high radiation count is possibly due to the uranium and thorium in the detrital materials, as well as the enrichment of radioelements in the feldspars (k-feldspar), calcite, quartz, zircon and clay minerals in the fluvial channel sandstones of the Beaufort Group. A total of two hundred and fifty-eight (258) rock samples were collected in the field and densities (dry, wet and grain densities) and porosities were determined in the laboratory. The Karoo Supergroup density values range from 2.526 – 2.828 g/cm3. The average porosities range from 0. 49 – 3.31 %. The dry densities and porosities of all the formations are inversely correlated with correlation coefficient values (R) that range from 0.9491 - 0.9982. The density of the dolerite intrusions (mostly sill) ranges from 2.700 – 2.837 g/cm3 whilst the porosity range from 0.1118 – 0.3868 %. The Bouguer anomaly map shows an increase in gravity values from -140.7 mGal in inland to about 60.1 mGal in coastal areas. This dominant gravity variation is inferred to be due to a deeper basement and/or Moho that get shallower from inland towards the coast. The Moho is at about 45 km depth inland and shallows to about 42 km at the coast. The 2½ D gravity modelling was done for fourteen (14) profiles with each profile having three (3) models corresponding to minimum, average and maximum densities to obtain the thicknesses of the geologic sequence. The current isochore thicknesses extracted from the gravity models show that the Beaufort Group is the thickest of all the groups that make up the Karoo Supergroup with maximum vertical thickness of up to 634 m, followed by the Ecca and Dwyka Groups with maximum vertical thicknesses of about 3207 m and 727 m, respectively. The maximum elevation for the Dwyka, Ecca and Beaufort sediments are about 500 m, 400 m and 285 m, respectively, whilst the maximum depth below sea level are around 8500 m, 7000 m and 5500 m, respectively. The PetroMod1D model result yield average vitrinite reflectance and temperature values of about 6 % and 500 ℃ respectively for the lower Ecca Group which belong to the dry gas window based on classification by several authors. Thus the rocks of the lower Ecca Group are thermally matured for hydrocarbon (shale gas) generation that can merit gas exploration in the Karoo Basin.
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- Date Issued: 2015
Identification and documentation of ethnobiological methods used by rural farmers to control stalk borers on maize in the Eastern Cape Province of South Africa
- Authors: Skenjana, Nolitha Leonora
- Date: 2015
- Subjects: Ethnobotany , Stem borers , Biological pest control agents -- South Africa , Corn -- Diseases and pests -- South Africa
- Language: English
- Type: Thesis , Masters , MSc (Ethnobotany)
- Identifier: vital:11312 , http://hdl.handle.net/10353/d1019852 , Ethnobotany , Stem borers , Biological pest control agents -- South Africa , Corn -- Diseases and pests -- South Africa
- Description: Maize contributes substantially to food security in the Eastern Cape province of South Africa. It is a staple food to many of the province’s rural and urban inhabitants. Insect pests are one of the factors that hamper its productivity and as a result, deprive farmers of good yields. The adverse effects of insecticides and the high cost associated with them and the cost of transgenic seeds are some of the challenges faced by small-scale farmers in rural areas. Alternative control methods which include the use of indigenous techniques to control pests are now sought. A study to identify and document ethnobiological means used by rural farmers to manage insect pests of maize was conducted in the rural areas of the Eastern Cape Province. A total of 217 participants were interviewed on the matter, using semi-structured but detailed questionnaires. Rural farmers due to their linkage to agriculture activities and the fact that they are considered as custodians of agricultural indigenous knowledge were selected as respondents. Only maize producing and IsiXhosa speaking people were chosen to contribute. Main focus was on the demography of respondents, crop production activities and insect pest control. Pretesting of the questionnaire in order to assess the appropriateness of questions and comprehension by both farmers and enumerators was done. Data was analysed using descriptive statistics. Fifty five percent (55 %) of the respondents were females and the highest number of participants was from the Chris Hani District Municipality. Majority of the people were unemployed or pensioners. Most had only attended primary school and the mean age was 59 years. Apart from maize, respondents were cultivating other crops such as cabbage, Swiss chard, potatoes etc. Stalk borers followed by cutworms were the main pests of maize in these areas. Respondents used mainly insecticides, followed by alternative substances, which also included cultural control methods such as planting date manipulation. Few respondents used plants as control agents for insect pests. Some people did not control pests even though they were a problem in their fields. The most used plant was Chenopodium ambrosiodes L, while the most used substance was Madubula (a detergent). The most used insecticide was carbaryl from the carbamite family. Respondents listed different preparation techniques for all the control methods mentioned. These techniques revealed different times of preparation, quantities of ingredients, amounts applied on plants, modes of application and intervals of application. Rural farmers in the study areas used different atypical methods which may play a significant role in pest management today. Some of the products may have a positive influence on agriculture, while some are dangerous to humans and environmental health. Further research which will investigate their potential use in pest control needs to be done.
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- Date Issued: 2015
Identification of agricultural and industrial pollutants in the Kat River, Eastern Cape and their effect on agricultural products found along the river banks
- Authors: Mutingwende, Nhamo
- Date: 2015
- Subjects: Environmental toxicology , Rivers -- Environmental aspects -- South Africa , Water -- Pollution -- Toxicology -- South Africa
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11291 , http://hdl.handle.net/10353/d1020242 , Environmental toxicology , Rivers -- Environmental aspects -- South Africa , Water -- Pollution -- Toxicology -- South Africa
- Description: There is growing concern that commonly used Pharmaceuticals and Personal Care Products (PPCPs) and pesticides are entering and contaminating drinking water supplies. The use of targeted quantitation of PPCP has been well established but there is an emerging trend to also screen for and identify unexpected environmental pollutants. Chemicals like pesticides hormones and antibiotics are especially of interest because of proven endocrine disrupting effects and a possible development of bacterial resistance. Powerful screening methods are required to detect and quantify the presence of these compounds in our environment. PPCP encompass a wide range of pollutants, including Endocrine Disrupting Compounds (EDC), pesticides, hormones, antibiotics, drugs of abuse, x-ray contrast agents and drinking water disinfection by-products to name a few. In order to properly assess the effects of these compounds on our environment, it is necessary to accurately monitor their presence. The diversity of chemical properties of these compounds makes method development challenging. LC/MS/MS is able to analyse polar, semi-volatile, and thermally labile compounds covering a wide molecular weight range. The new AB SCIEX TripleTOF™5600 LC/MS/MS was used to profile environmental samples for unexpected pollutants, to identify and characterise the chemical composition and structure of the pollutants, and to quantify (based on intensity) the concentration in collected water samples. Liquid Chromatography coupled to tandem Mass Spectrometry (LCMS/ MS) is able to analyse polar, semi-volatile, and thermally labile compounds covering a wide molecular weight range, such as pesticides, antibiotics, drugs of abuse, x-ray contrast agents, drinking water disinfection by-products etc. More recently there is a growing interest from environmental researchers to also screen for and identify non-targeted compounds in environmental samples, including metabolites and degradates, but also completely unexpected pollutants. The new AB SCIEX TripleTOF™5600 LC/MS/MS system is capable of performing highly sensitive and fast MS scanning experiments to search for unknown molecular ions while also performing selective and characteristic MS/MS scanning for further compound identification and, therefore, is the instrument of choice for this challenging task. General unknown screening workflows do not use a target analyte list and compound detection is not based on any prior knowledge, including retention times and information on possible molecular and fragment ions. Therefore, acquired chromatograms are very rich in information and can easily contain thousands of ions from both any compounds present in the sample as well as from the sample matrix itself. Thus, powerful software tools are needed to explore such data to identify the unexpected compound. Water samples were collected both upstream and downstream of two WWTPs (Seymour and Fort Beaufort) and were directly injected on the AB SCIEX TripleTOF™5600 LC/MS/MS after being filtered. 15 sample points along the Kat River, ranging from a point as close to the source as possible to a point just before it joins the Great Fish River were used. The samples collected from the source were used as the control in each of the experiments, the assumption being the closer you get to the source, the less contaminated the water would be for the analysis of pesticides. Points were selected where the Kat River crosses the R67 or on farms where the river was accessible using farm roads. Samples were collected from October 2013 to November 2014.The Peak view software and Analyst software were used in the analysis of PPCPs. The XIC Manager allows you to manage large lists of compounds and perform automatic extracted ion chromatogram (XIC) calculations and review results operations. The results were displayed in the chromatogram pane and the XIC table (see results). The results reported here in this thesis indicate that there is contamination in the Kat River water due to both pesticides and PPCPs. The results also indicate that the food products are also contaminated and hence both the Kat River agricultural produce and its water need to be closely monitored for both pesticide and PPCPs contaminants. Further studies to investigate the quantitative levels of pesticides and PPCPs in the Kat river water to determine if the concentration levels of the detected pesticides are below the reported Maximum Residues Limits will be explored in the future.
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- Date Issued: 2015
Investigation into the characteristics and possible applications of biomass gasification by-products from a downdraft gasifier system
- Authors: Melapi, Aviwe
- Date: 2015
- Subjects: Biomass gasification -- South Africa -- Eastern Cape , Renewable energy sources -- South Africa -- Eastern Cape , Biomass energy -- South Africa -- Eastern Cape , Crop residue management -- South Africa -- Eastern Cape , Coal gasification -- South Africa -- Eastern Cape , Lignocellulose -- Biodegradation -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11348 , http://hdl.handle.net/10353/d1020174 , Biomass gasification -- South Africa -- Eastern Cape , Renewable energy sources -- South Africa -- Eastern Cape , Biomass energy -- South Africa -- Eastern Cape , Crop residue management -- South Africa -- Eastern Cape , Coal gasification -- South Africa -- Eastern Cape , Lignocellulose -- Biodegradation -- South Africa -- Eastern Cape
- Description: Biomass gasification has attracted the interest of researchers because it produces zero carbon to the atmosphere. This technology does not only produce syngas but also the byproducts which can be used for various application depending on quality.The study conducted at Melani village in Alice in the Eastern Cape of South Africa was aimed at investigating the possible applications of the gasification byproducts instead of being thrown away. Pine wood was employed as the parent feedstock material for the gasifier. Biomass gasification by-products were then collected for further analysis. The studied by-products included tar(condensate), char, soot and resin. These materials were also blended to produce strong materials.The essence of the blending was to generate ideal material that is strong but light at the same time.The elemental analysis of the samples performed by CHNS analyser revealed that carbon element is in large quantities in all samples. The FTIR spectra showed almost similar results for all the studied samples, since the samples are end products of lignocellulosegasification. SEM gave the sticky images of resin as well as porous char structures. Char showed a higher heating value of 35.37MJ/Kg when compared to other by-products samples.
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- Date Issued: 2015
Isolation and characterisation of lignocellulose degrading bacteria from Tyume River in the Eastern Cape Province, South Africa
- Authors: Tembisa, Papiyana Ayavuya
- Date: 2015
- Subjects: Lignocellulose -- Biodegradation -- South Africa -- Eastern Cape , Bacillus (Bacteria) -- South Africa -- Eastern Cape , Waterborne infection -- South Africa -- Eastern Cape , Bacteriophages -- South Africa -- Eastern Cape , Sediments (Geology) -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11299 , http://hdl.handle.net/10353/d1021293 , Lignocellulose -- Biodegradation -- South Africa -- Eastern Cape , Bacillus (Bacteria) -- South Africa -- Eastern Cape , Waterborne infection -- South Africa -- Eastern Cape , Bacteriophages -- South Africa -- Eastern Cape , Sediments (Geology) -- South Africa -- Eastern Cape
- Description: This study focuses on the isolation and characterization of bacteria from lignocellulosic biomass obtained from the sediments of the Tyume River in Alice, Eastern Cape and to determine those bacterial isolates with good potential for modification and decomposition of lignocellulosic biomass for industrial application. Several bacterial isolates were recovered and screened for ability to degrade various lignocellulosic materials. Nine of the isolates were positive for lignocellulolytic activity. Four isolates were cellulase positive and six were xylanase positive. Moreover, one isolate (SB1) was positive for both xylanase and cellulase activities and showed the best hydrolysis zone on solid media. This isolate was then chosen as the best and identified molecularly. The 16S rDNA sequence analysis indicated that SB1 was a Bacillus cereus species. Factors affecting the cellulose and xylanase enzyme production by the organisms were studied. The organisms produced the enzymes maximally at earlier hours of incubation (12-30 hr) and optimally at acidic pH (3-5) and at moderate temperatures (35-45ºC). SB1 appears to hold promise in the decomposition of lignocellulosic wastes.
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- Date Issued: 2015
Isolation and molecular characterization of Bacillus cereus from cow’s raw milk
- Authors: Lukanji, Zinathi , Ndip, R N
- Date: 2015
- Subjects: Milk contamination -- South Africa -- Eastern Cape , Bacillus (Bacteria) -- South Africa -- Eastern Cape , Foodborne diseases -- Molecular diagnosis -- South Africa -- Eastern Cape , Dairy products -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11296 , http://hdl.handle.net/10353/d1021284 , Milk contamination -- South Africa -- Eastern Cape , Bacillus (Bacteria) -- South Africa -- Eastern Cape , Foodborne diseases -- Molecular diagnosis -- South Africa -- Eastern Cape , Dairy products -- South Africa -- Eastern Cape
- Description: Bacillus cereus is a group of ubiquitous facultative anaerobic spore forming Gram-positive rods commonly found in soil. It has been detected and implicated in several contaminated food products and raw milk in dairy farms and it causes foodborne gastroenteritis by producing several toxins. This study is aimed at characterizing virulence determinants of B. cereus from cow‟s raw milk. A total of 400 raw milk samples were collected in Fort Hare Dairy Trust and Middledrift Dairy Farm; and cultured on Polymyxin pyruvate Egg-Yolk Mannitol Bromothymol Agar (PEMBA) for 48 hours at 37°C. DNA was isolated from the isolates and 16S rDNA was amplified and sent to Central Analytical Laboratory for sequencing. The gyrB gene of B. cereus was also used to confirm the identity of the isolates. Antibiotic susceptibility profiles of the isolates together with virulence genes were investigated. Multilocus Sequence typing was used to investigate the genetic relatedness of some selected isolates. Furthermore, spores of the isolates were produced, harvested and their concentrations determined. All (100%) of the isolates were identified as having a 96-99% similarity to B. cereus, B. thuringiensis and B. anthracis using sequencing; while gyrB gene was observed in all (100%) of the isolates. Three virulence genes nheA, nheB, nheC encoding for non haemolysin enterotoxin were amplified in all (100%) the isolates. All (100%) of the isolates were susceptible to doxycycline, gentamycin, tetracycline, ciprofloxacin, chloramphenicol and streptomycin. Resistance to rifampicin and penicillin G was predominant with equal rate of 100%, while susceptibility to erythromycin, clindamycin and doxycycline ranged from 60% to 100%. The selected isolates were related and are descendants of the same ancestor. All (100%) the isolates produced spores. The B. cereus isolates contain virulence genes, has multiple antibiotic drug resistance and produce spores, which poses a health risk to the public and cannot be used as probiotics.
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- Date Issued: 2015
Microbiological analyses of beef slaughtering process and meat safety knowledge of handlers at selected high and low thoughput abattoirs
- Authors: Nyamakwere, Faith
- Date: 2015
- Subjects: Slaughtering and slaughter-houses -- South Africa -- Eastern Cape Meat industry and trade -- Quality control Beef -- Quality -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2238 , vital:27712
- Description: The objective of the study was to evaluate meat hygiene practices among meat handlers and microbiological analysis of beef carcasses, slaughtermen hands, equipment and water from low throughput (LTA) and high throughput (HTA) abattoirs in the Eastern Cape Province of South Africa. In stage one of the study, the level of knowledge, practices and attitudes towards meat safety and personal hygiene of slaughtermen were assessed. Forty workers directly involve in beef cattle slaughtering process were surveyed. Data were collected using a structured questionnaire, it contained questions on some of the most important meat safety cues such as knowledge, attitudes, personal hygiene and handling practices. Cross tabulation and Chi-square Test of Association were performed to examine the relationships between the demographic information and the knowledge regarding meat safety using the Statistical Package for Social Sciences (SPSS) version 22. Overall, a significant adherence to basic hygiene practices and a satisfactory level of knowledge were observed. Workers from a HTA yielded comparatively better statistically significant scores. Moreover, knowledge and practices of respondents were significantly associated (P<0.05) due to educational level and professional training. The second stage of the study involved evaluating the level to which cattle carcass, equipment, slaughtermen hands and water were contaminated with Enterobacteriaceae, Salmonella, Escherichia coli and aerobic colony counts (ACC) at different stages during the slaughter process (skinning, evisceration, carcass slitting, inspection, washing and packing). Cattle carcasses were sampled at four sites (rump, neck, flank and brisket) from a LTA (n= 240) and HTA (n= 384) abattoirs. Using conventional biochemical tests, HTA yielded significantly (P<0.05) higher ACC (5.2 log CFU/cm2), E. coli (2.6 log CFU/cm2) and Enterobacteriaceae (2.9 log CFU/cm2) carcass mean scores than LTA after skinning and evisceration. Specific abattoir hygiene differences were noted from washed and chilled carcasses. Salmonella was not detected across all sampled slaughter process stages. In addition, the equipment had bacterial load ranging from 10 to 4 CFU/cm2 for LTA, whereas in HTA this was found to be 7 to 3 CFU/cm2. The bacterial counts for slaughtermen hands were estimated to be 15 to 8 CFU/cm2 in HTA and 10 to 5 CFU/cm2 in LTA. Overall, slaughtermen hands and equipment in the dirty area (skinning and evisceration) yielded more bacterial counts compared to those in the clean area (slitting, inspection, washing and packing) from both abattoirs. For all the sampled carcasses, equipment and slaughtermen hands, HTA yielded comparatively higher (P<0.05) bacterial counts than the LTA. Although the results showed a significant adherence to basic hygiene practices, some aspects such as routine medical examination, health certificates and professional training of slaughtermen still need to be improved. Therefore, these findings show that slaughtermen, equipment and water can be sources of contamination during the slaughter process.
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- Date Issued: 2015
Ni(II) and Pb(II) dithiocarbamate complexes as precursors for the synthesis of HDA-capped NiS and PbS nanoparticles
- Authors: Chintso, Thobani
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11349 , http://hdl.handle.net/10353/d1020201
- Description: Ni(II) and Pb(II) dithiocarbamate complexes were synthesized and characterized by elemental analysis, UV-Vis, FTIR and TGA and some of the Ni(II) complexes and one Pb(II) were further analyzed by 1H-NMR and 13C-NMR spectroscopy. Generally all the dithiocarbamate ligands are soluble in water while the complexes were soluble mostly in solvents such as chloroform, toluene, DMSO and DCM. Based on the elemental analysis, the dithiocarbamate complexes are formulated as four coordinate (tetrahedral or square planar) compounds. However, the FTIR showed that each of the dithiocarbamate ligands acted as bidentate ligand through two sulfur atoms. The TGA of the most complexes showed one major decomposition step to give respective metal sulfide above 200 oC. In this research project, dithiocarbamate complexes were used as single source precursor for the synthesis of metal sulfide nanoparticles. We studied the optical and structural properties of metal sulfide nanoparticles using UV-Vis, photoluminescence (PL), powder X-ray diffraction (XRD), energy dispersive X-ray (EDX), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The absorption spectra of the metal sulfide nanoparticles are blue shifted in respect to bulk material and they also showed broad emission. The XRD of the NiS nanoparticles were indexed to the cubic and rhombohedral phase, with crystallite sizes of 15 - 18 nm. The XRD of PbS nanoparticles were indexed to the face centered cubic and cubic rock salts, with the crystallite sizes 12 - 18 nm. The TEM images of the metal sulfide nanoparticles showed particles with spherical and rectangular shapes with crystallite sizes 4 - 35 nm.
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- Date Issued: 2015
Perceptions of indigenous people regarding mental illness at Cacadu District in the Eastern Cape Province of South Africa
- Authors: Tilolo, Lwazi Romeo
- Date: 2015
- Subjects: Indigenous peoples -- Mental health -- South Africa -- Eastern Cape Cultural psychiatry -- South Africa -- Eastern Cape Healers -- South Africa -- Eastern Cape , Ethnopsychology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2677 , vital:27983
- Description: Indigenous people tend to consult traditional healers when a family member manifests change in behaviour, whilst conventional treatment disregards spirituality when preserving mental health. The aim of the study was to explore the perceptions of indigenous people and the role of traditional healers in the management of mentally ill persons within the Cacadu District in the Eastern Cape Province of South Africa. The study has adopted a qualitative approach which was exploratory and descriptive in nature. The sample consisted of nine relatives of mental health care users (MHCUs) and six traditional healers. Ethical principles were also taken into consideration by the researcher during the process of conducting the study. Data were collected from two strata, namely, relatives of the MHCUs and the traditional healers and an interview guide was used to conduct in-depth face-to-face interviews. Data were analysed using Tesch’s method of data analysis. Four themes emerged from the data categories and sub categories were identified. According to the themes participants indicated the negative impact of mental illness; as a result they portrayed great desperation regarding the means of accessing a cure for mental illness. Some participants showed insufficient knowledge regarding mental illness and had different perceptions and beliefs regarding the origin of mental illness. Available literature was used to emphasise and support the views that were expressed by both traditional healers and relatives of MHCUs. It has been highlighted from this study that indigenous people of Cacadu District view mental illness as spiritual in origin but they include Western medication for the benefit of the mentally ill. In addition, the relatives of the MHCUs highlighted the economic burden as the major problem that results from mental illness.
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- Date Issued: 2015
Phytochemical analysis and antibacterial properties of aqueous and ethanol extracts of Brachylaena elliptica (Thurb.) dc. and Brachylaena ilicifolia (Lam.) Phill & Schweick
- Authors: Sagbo, Idowu Jonas
- Date: 2015
- Subjects: Medicinal plants , Traditional medicine , Herbs -- Therapeutic use
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11297 , http://hdl.handle.net/10353/d1021289 , Medicinal plants , Traditional medicine , Herbs -- Therapeutic use
- Description: Resistance of human pathogenic bacterial strains results in selective pressure against known antibiotic. However, plant derived compounds that possess antibacterial potential are currently being investigated for treatment of wound infections in diabetic patients as they are inexpensive and non-toxic. Hence, this dissertation was designed to evaluate two medicinal plants (Brachylaena elliptica and Brachylaena ilicifolia) traditionally used in the treatment of various diseases such as diabetes, and its secondary complications in diabetic patients. The in vitro antioxidant activity of both plants were evaluated using DPPH (1, 1-diphenylhydrazl), ferric reducing power, ABTS (2, 2’-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid), NO (nitric oxide) and H2O2 (hydrogen peroxide) techniques. The antibacterial test and Minimum inhibitory concentration (MIC) was determined by agar dilution method against 5 bacteria strains (Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus pyogene, Proteus vulgaris and Proteus mirabilis) infecting wounds in diabetic patients using amoxicillin and ciprofloxacin as positive control. The phytochemical analyses were assessed using standard published methods. Identification of bioactive components in essential oils of both plants were assessed using GCMS. The aqueous and ethanol extracts of both plants were also evaluated to identify bioactive components using LC-MS. The results of the phytochemical analysis revealed the presence of phenols, tannins, flavanoids, flavanols, proanthocyanidins, saponins and alkaloids in both plants. Both plants indicated strong antioxidant activities which might be due to the presence of bioactive compounds. The aqueous and ethanol leaf extracts of both plants demonstrated appreciable broad spectrum activities against these wound pathogens with MIC ranging between 5 and 0.3 mg/ml. The GC-MS analysis of the essential oils of both plants revealed the presence of monoterpenes, oxygenated sesquiterpenes, phenolics and esters. The LC-MS analysis of the aqueous and ethanol leaf extracts of both plants showed that both plants are rich in alkaloids, terpenes, terpenoids, monoterpernoids, and flavanoids. Conclusively, this study has partially justified the ethnomedicinal use of B. elliptica and B.licifolia leaves for the treatment of various diseases, including diabetes and wound infections caused by bacteria in diabetic patients. These may be attributed to the presence of antioxidant compound such as phenols, flavanoids, saponins, tannins, alkaloids and other phytochemical compounds.
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- Date Issued: 2015
Prevalence and antibiogram of some swine associated Shiga toxin producing Escherichia coli Serogroups and Salmonella species in Nkonkobe Municipality, Eastern Cape Province, South Africa
- Authors: Iwu, Chinwe Juliana
- Date: 2015
- Subjects: Escherichia coli -- South Africa -- Eastern Cape , Salmonella infections -- South Africa -- Eastern Cape , Water -- Pollution -- Environmental aspects -- South Africa -- Eastern Cape , Escherichia coli infections -- South Africa -- Eastern Cape , Water quality management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11294 , http://hdl.handle.net/10353/d1021273 , Escherichia coli -- South Africa -- Eastern Cape , Salmonella infections -- South Africa -- Eastern Cape , Water -- Pollution -- Environmental aspects -- South Africa -- Eastern Cape , Escherichia coli infections -- South Africa -- Eastern Cape , Water quality management -- South Africa -- Eastern Cape
- Description: Gastrointestinal illnesses have continually become a global public health issue. Exposure to zoonotic food borne pathogens such as Salmonella and diarrhoegenic E. coli either by direct or indirect contact through the consumption of food producing animals is likely an important mode of infection to humans. More so, the use of antibiotics in farm animals similar to those used in humans can select for resistance in bacteria frequently harboured by them. These resistant strains can be passed on to humans through contaminated meat products and water leading to resistant infections with consequences such as prolonged illnesses, treatment failures, and increased morbidity and mortality. In animals, these can lead to reduced productivity. Monitoring the level of resistance among bacteria from animal isolates will help in generating data that could be used to create awareness of their presence in the environment and aid in preventing a potential epidemic in the community. In this study, we investigated the prevalence and antimicrobial resistance profile of Escherichia coli serogroups and Salmonella species in faecal samples collected from pigs in Nkonkobe Municipality in the Eastern Cape Province, South Africa between April – July, 2014. A total of 310 presumptive Shiga toxin producing Escherichia coli (STEC) were confirmed as E. coli spp using polymerase chain reaction (PCR) technique by amplification of the uidA gene, out of which 179 (58%) were confirmed positive. Approximately, serogrougs O157:H7, O145 and O26 made up 24% (n=43), 8% (n=14) and 20% (n=35) of the E. coli population respectively. Only E. coli O26 was positive for stx2 gene in 31% of the isolates harbouring the gene, while the other serogroups were non-pathogenic. Susceptibility of the isolates to 18 antibiotics was carried out in vitro by the standardized agar disc-diffusion method. All the isolates were susceptible to imipenem. Similarly, a relatively high susceptibility was observed in norfloxacin (83-100%), ciprofloxacin (63-100%), gentamycin (77-100%), and chloramphenicol (77-100%). However, all the isolates were resistant to tetracycline and its long acting counterpart oxytetracycline. Resistances observed against other antimicrobials are as follows: ampicillin (84-91%), streptomycin (14-100%), erythromycin (91-100%), ceftazidime (35%). Multiple antimicrobial resistance patterns and indices ranged from 3 to 12 and 0.2 to 0.7 to respectively. Genes encoding resistances to ampicillin (ampC), streptomycin (strA) and tetracycline (tetA) were frequently detected in 50-100%, 22-29% and 40-86% of the resistant isolates respectively. In the other arm of the dissertation, two hundred and fifty eight presumptive isolates of Salmonella were recovered from the faecal samples of pigs. Specific primers targeting serogroups A, B, C1, C2, and D were used to delineate the isolates into different serogroups using PCR. Only serogroup A (n=48) was detected. These isolates were examined for antimicrobial susceptibility by disc diffusion method using 18 antibiotics. The results showed that a large proportion of the isolates were resistant to tetracycline (100%), oxytetracycline (100%), ampicillin (75%), sulphamethoxazole/trimethoprim (75%) and streptomycin (75%). Majority of the isolates exhibited multidrug resistances with the predominant multiple antibiotic resistance (MAR) phenotype being against eleven antibiotics. A high multiple antibiotic resistance (MAR) index in a range of 0.3- 0.6 was observed. The incidence of genes encoding resistance against tetracycline (tetA), streptomycin (stra), and ampicillin (ampC) were 54%, 44% and 61% respectively. These findings reveal that pigs within the Nkonkobe Municipality in the Eastern Cape Province could harbour Shiga toxins and multidrug resistant serogroups of E. coli as well as resistant Salmonella which could be transmitted to humans through the food chain. To ensure public health safety, continuous monitoring and sufficient sanitation in swine industries must be ensured.
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- Date Issued: 2015
Regional differentiation of three goatfishes (Parupeneus Spp.) within the Western Indian Ocean
- Authors: Springbok–Njokweni, Nosiphiwo
- Date: 2015
- Subjects: Marine fishes -- South Africa , Mitochondrial DNA -- South Africa , Mullidae -- South Africa , Biogeography -- South Africa
- Language: English
- Type: Thesis , Masters , MSc (Zoology)
- Identifier: vital:11798 , http://hdl.handle.net/10353/d1020262 , Marine fishes -- South Africa , Mitochondrial DNA -- South Africa , Mullidae -- South Africa , Biogeography -- South Africa
- Description: Goatfishes inhabit inshore reefs and corals and are commercially important across their distribution in the Western Indian Ocean (WIO). The biogeography of these species in the WIO has not been explored with regards to their levels of diversity and relationships among regions. The genetic connectivity and differentiation of three goatfishes of the genus Parupeneus (P. barberinus, P. macronemus and P. rubescens) was studied using two mitochondrial genes (ND2 and 16S rRNA) and one nuclear gene (RAG1) using specimens from East and southern Africa, islands around the Mascarene plateau, Oman, Maldives and the Red Sea. Haplotype diversities, networks and AMOVA were used to measure genetic variance among localities and defined regional groups. There were high haplotype (HD > 0.9) and low nucleotide diversities (< 0.006) among all species for all gene regions, suggesting high levels of genetic differentiation among different areas, except for the mtDNA 16S data for P. macronemus and P. rubescens. For all three species, the FST population pairwise values revealed significant differentiation in all datasets for most population pairwise comparisons with the Maldives and genetic connectivity with haplotypes being shared among other localities. The 16S and RAG1, AMOVA for P. barberinus revealed a significant (P < 0.05) strong genetic structure among groups, for example P = 0.00 was estimated in the 16S data for four groups (the Maldives, WIO islands, Kenya and eastern mainland). This study found evidence for regional differentiation within the WIO for these three species supporting the presence of genetic breaks among areas. This differentiation could be either due to the historical isolation among areas or due to geographic and oceanic barriers such as the Mascarene Plateau and the Agulhas Current eddies in the Mozambique Channel. The effects of oceanographic features and physical barriers in the species distribution range and the dispersal potential based on the life history features of the species can have an influence on the genetic structuring of a population. It is also important to note that the length of the pelagic larval phase is just one factor affecting dispersal in marine organisms that can also explain the difference in genetic population structure. Unfortunately there is no specific information on the larval dispersal of these three goatfish. Therefore, studies are needed to be conducted on the specific biology and life history strategies of each Parupeneus species. These results suggest the importance of other factors, such as currents, and larval retention that may cause strong differentiation. These factors should also be considered when observing larval dispersal and its effect on population genetic structure. This study support the hypotheses that physical factors, processes (geographic barriers and oceanographic characteristics) and life history parameters need to be studied to understand the genetic differentiation of these Parupeneus reef fishes.
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- Date Issued: 2015
Socio-economic factors influencing the adoption of in-field rainwater harvesting technololgy for enhancing household food security by small holder farmers in the Nkonkobe Municipality, Eastern Cape Province
- Authors: Shange, Nomfundo Sinethemba Queen
- Date: 2015
- Subjects: Farms, Small -- South Africa -- Eastern Cape , Water harvesting -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape , Water resources development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: http://hdl.handle.net/10353/734 , vital:26492 , Farms, Small -- South Africa -- Eastern Cape , Water harvesting -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape , Water resources development -- South Africa -- Eastern Cape
- Description: Infield rainwater harvesting (IRWH) technology has been used in arid and semi-arid parts of the world and promising results have been achieved in terms of increasing yield. The main aim of this study was to identify socio-economic factors determining the adoption of IRWH technology for enhancing household food security by smallholder farmers. The specific objectives were to assess the level of adoption of IRWH technology using descriptive statistics (mean, frequency and percentages). To determine socio-economic factors influencing adoption of IRWH technology, the binary logistic regression mode l was used. To determine whether adopters of IRWH technology are more food secure than non-adopters, the Household Dietary Diversity Score (HDDS) was used as a measure for household food security. For the same objective, to determine socio-economic factors that influence household food security, the binary logistic regression model was also used and adoption of IRWH technology became an independent variable. The study was conducted in Khayalethu, Guquka and Krwakrwa villages in Nkonkobe Municipality in the Eastern Cape Province (EC). The unit of analysis was the individual smallholder farmers practicing agriculture. The availability (accidental) and snowball sampling techniques were used to select 34, 23, 63 respondents from Khayalethu, Guquka and Krwakrwa villages respectively. Since they are non-random, these sampling methods are problematic because of sampling errors. Overall, a sample size of 120 smallholder farmers was targeted for the interviews. Primary and secondary data collected was coded and analysed using statistical package for social sciences (SPSS) version 21. Results were presented using graphs, pie charts and tables (including cross-tables). The descriptive results showed that adoption status of IRWH technology was low in these areas, with 79% not adopting the technology. Food insecurity was high amongst the non-adopters with 86%. On the basis of descriptive analysis it can be concluded that any change in each one of the significant variables can significantly influence the probability of adopting IRWH technology and household food security. The results from the logistic regression model for the incidence of adoption revealed that 6 out of 16 variables were significant, three at 1% (access to extension services, access to information and farmers’ perception towards the IRWH technology); one at 5% (access to market) and two at 10% (access to hired labour and farm income). For the incidence of household food security, out of 17 variables, 6 were significant, three at 1% (adoption of the IRWH technology, access to extension services and farmers’ perception towards the IRWH technology); two at 5% (access to hired labour and household income) and one at 10% (household size). The empirical findings of this study indicate that there are socio-economic factors influencing adoption of IRWH technology and household food security amongst smallholder farmers. This study recommends that the government should provide extension officers and research stations with the capacity, support and physical means to expose smallholder farmers to the IRWH technology through demonstrations and trainings. The government can also introduce agricultural finance institutions in rural areas to assist the rural smallholder farmers to increase their access to credit. Further, it is recommended that smallholder farmers can expand to the communal croplands in order to gain more land size and work as a co-operative or as an association to ease labour constraints.
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- Date Issued: 2015
Stratigraphy and sedimentology of the Msikaba formation in KwaZulu Natal South Coast, South Africa
- Authors: Busakwe, Nolukholo Sinovuyo
- Date: 2015
- Subjects: Geology, Stratigraphic Sedimentology -- South Africa -- KwaZulu-Natal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2501 , vital:27877
- Description: The Msikaba Formation is a Late Devonian fluvial and marine succession which outcrops from Hibberdene to Port Edward along the south coast of KwaZulu-Natal Province, South Africa. The Formation is composed of brownish conglomerate at the bottom and white-greyish quartz arenite sequence in the middle and mixed quartz-arenite with feldspathic sandstone in the upper sequence. Previous studies put more emphasis on the correlation of Msikaba Formation with the Natal Group and Cape Supergroup, whereas this study revised the stratigraphy, and also put new insight on the petrography, sedimentary facies, depositional environments and diagenesis of the Formation. The total stratigraphic section attains a thickness of 184 m at Margate area and 186 m at Port Edward area. The stratigraphy of Msikaba Formation is well exposed on the outcrops along the KwaZulu-Natal coastline. The stratigraphy is subdivided into 4 new members along Margate to Shelly beach section; namely Manaba Member, Uvongo Member, Mhlangeni Member and Shelly Beach Member from bottom upward. Twelve sedimentary facies were identified and the sedimentary facies were integrated into 4 facies association: Facies association 1 (Gmm+Sm) represents braided fluvial deposits, Facies association 2 (Gcm+St+Sp+Sl+Shb) represents tidal channel and tidal flat deposit, Facies association 3 (St+Sp+Sr+Sl) is result of shallow marine deposit and Facies association 4 (Sp+Sl+St+Sm) is a mixed marine and fluvial deposit. Each facies association represents a specific stratigraphic unit and were deposited in a specific sedimentary environment. Grain size analysis was conducted on seventeen thin sections and 500 grains were counted from each thin section. The sandstone grain size parameters of mean, sorting, skewness and kurtosis fell under the average of 0.75, 0.78, 0.4 and 1.2φ respectively. The results show that most of the grain size are coarse to medium grained throughout the study areas and sorting of the sandstones are moderate to poorly sorted. The cumulative frequency diagrams and bivariate plots show positive skewness and negative kurtosis, which indicate a high hydrodynamic environment. Modal composition analysis and petrography studies show that detrital components of the Msikaba Formation are dominated by monocrystalline quartz, feldspar (mostly K-feldspar) and lithic fragments of igneous and metamorphic rocks. The sandstones could be classified as quartz arenite, sub-arkosic sandstone and feldspathic litharenite; and the provenance analysis indicates that the sandstones were derived from craton interior, recycled or quartzose recycled sources which may derived from weathering and erosion of igneous and metamorphic rocks. Diagenetic processes of the Msikaba Formation have been passed through early, mid- and late diagenetic stages. Cementation, mineral conversion and compaction affect early diagenetic stage; authigenic minerals, quartz and feldspar overgrowth are presented in mid-diagenetic stage, whereas recrystallization, replacement, deformation and dissolution have been strongly affected late diagenetic stage. Microscopy, XRD and SEM-EDX studies have identified five types of cements including smectite clay, kaolinite, hematite, quartz and feldspar cements. Quartz cement, pore-filling and pore-lining clay are the major type of cements in the Msikaba Formation. Based on the lithology, sedimentary structure and facies variations, the Manaba Member was most probably deposited in a braided fluvial environment, the Uvongo Member was deposited in a tidal channel environment, the Mhlangeni Member was formed in shallow marine storm-influenced environment, whereas the Shelly Beach Member was represented mixed marine and fluvial environment. The sequence stratigraphy of Msikaba Formation constitutes a transgressive sequence from Manaba Member to Uvongo Member, whereas it ended as a regressive sequence from Mhlangeni Member to Shelly beach Member. The Msikaba Formation shows major differences with the Natal Group and Table Mountain Group (Cape Supergroup) in the lithology, stratigraphic sequence, sedimentary structures, facies system, palaeocurrent styles, fossil contents and depositional environments, which demonstrate that they are not the equivalent stratigraphic unit. Therefore, the Msikaba Formation is a separate, younger stratigraphic unit, and cannot correlate with the Natal Group and Table Mountain Group as suggested by previous researchers.
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- Date Issued: 2015
Synthesis and characterization of Ru(II) phenyl-3-indenylidene olefin metathesis type complexes
- Authors: Yalezo, Ntsikelelo
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11351 , http://hdl.handle.net/10353/d1021128
- Description: In this study, a series of Ru(II) phenyl-3-indenylidene complexes with general formula of [RuCl2(NHC)(Ind)(L)] (where L= triphenylphosphine, pyridine and NHC = five different types of N-heterocyclic carbene ligands), have been synthesized and characterized using FT-IR, UV-Vis, elementally analysis and melting/decomposition point. The N,N’-diarylimidazolinium chlorides have been used as N-heterocyclic carbene precursors and were synthesized from their corresponding N,N’-diarylformamidines and further characterized using 1H-NMR, 13C-NMR, FTIR and melting point determination. The infrared spectra of the N,N’-diarylimidazolinium chlorides show a quaternary nature (R2N=C+) with broad vibration band in region 3300-3400 cm-1. The disappearance of this vibration band in the infrared spectra of the ruthenium(II) complexes was used to confirm the coordination of the ligand to the ruthenium ions. The percentage analysis of carbon, hydrogen and nitrogen obtained corresponded with the calculated percentages of these atoms in the complexes with the slight difference of less than 1%. The electronic spectra of the complexes show three distinct absorption bands. The two bands are due to intraligand charge transfers transition assigned to π→π*, n→π* and third band is due to d-d transition, signifying the presence of the metal ion. The synthesized Ru(II) complexes did not show any of melting, however a change in colour was observed signifying the decomposition of the complexes.
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- Date Issued: 2015
Synthesis, characterisation and evaluation of functionalized Lignocelluloses-clay nanocomposites for organic pollutant removal from water
- Authors: Mafukidze, Donovan M
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11356 , http://hdl.handle.net/10353/d1021296
- Description: PMPSgLig-NaMMT nanocomposites were prepared from methacryloxypropyltrimethoxysilane (MPS), lignocellulose and montmorillonite clay. The potential enhancement of organic pollutant adsorption capabilities of PMPSgLig-NaMMT nanocomposite from water through functionalization was investigated. PMPSgLig-NaMMT was functionalized by esterification and etherification using different methods so as to increase the surface hydrophobicity of the material and hence improve its compatibility with the target pollutants. Specific chemical routes specially tailored for PMPSgLig-NaMMT were established for functionalization mostly based on the common esterification (Fischer esterification) and etherification (Williamson‟s etherification) reactions. In the functionalization methods, factors such as pH environment, nanocomposite composition, nature of functionalization moiety, and use of or absence of solvents and their variations were studied. FT-IR, XRD, SEM and TGA were used to characterize the synthesized and functionalized nanoadsorbents. The techniques showed successful functionalization via esterification and etherification methods albeit to different extents, with clear retention of the material‟s original structure though there were signs of degradation with some methods. Characterization was supported by adsorption studies to validate implications and draw conclusions. The use of 1,10-phenathroline as a model organic pollutant in water in the adsorption studies showed that adsorbents conformed to monolayer adsorption following pseudo-second order kinetics for adsorption of organic pollutants accurately represented. Most importantly the studies revealed the significant impact of the nanocomposite composition on the overall absorbent performance. Adsorption studies also showed that functionalization via esterification methods gave rise to better adsorbents.
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- Date Issued: 2015