List of Titles

Chemical evaluation, in vitro ruminal dry matter (DM) degradability and ruminal biological activity of common browse tree fruits of Alice

Authors: Sondzaba, Bavuyise
Date: 2020-01
Subjects: Ruminants
Language: English
Type: Master's theses , text
Identifier: http://hdl.handle.net/10353/20882 , vital:46695
Description: The objective of this study was to investigate the effect of species variations on chemical composition and in vitro ruminal degradability of Vachellia karroo, Grewia Occidentalis, Diospyros Lycioides and Ziziphus Mucronata fruits harvested from communally grazed lands in Alice, Eastern Cape Province, South Africa. The browse fruits were collected between February and May and analysed for crude protein (CP), dry matter (DM), ash, neutral detergent fibre (NDF), acid detergent fibre (ADF), organic matter (OM) and acid detergent lignin (ADL), condensed tannins (CT), macro minerals (Calcium (Ca), Magnesium (Mg), Potassium (K), Sodium (Na) and Phosphorus(P)) and micro minerals (Ion (Fe), Zinc (Zn), Manganese (Mn) and Copper (Cu)). There was significant variation (P<0.05) in chemical composition between browse fruits. The CP content differed significantly amongst the browse fruits, but all contained enough to meet the maintenance requirements of ruminants. Fruits from V. Karroo had higher (P<0.05) CP (182.26 g/kg DM), DM (896.50 g/kg DM) and ash (55.60 g/kg DM) contents compared to other browse species, while D. Lycioides fruits had higher (P<0.05) OM (951.60 g/kg DM) content than other browse fruits. Fruits harvested from G. Occidentalis had higher (P<0.05) ADF (513.27 g/kg DM), NDF (577.22 g/kg DM) and ADL (223.20 g/kg DM) content compared to other browse fruits. Fruits from V. Karroo had higher (P<0.05) CT (269.33 g/kg DM) content followed by Z. Mucronata (187.46 g/kg DM), while D. Lycioide (54.22 g/kg DM) and G. Occidentali (66.65 g/kg DM) had the same CT contents (P>0.05). There was a significant variation between browse species in macro and micro mineral contents. Fruits from G. Occindelis (43.93 g/kg DM) and V. Karroo (43.44 g/kg DM) had higher (P<0.05) Ca content compared to Z. Mucronata (24.06 g/kg DM) and D. Lycioides (20.06 g/kg DM). Ziziphus Muronata had higher (P<0.05) P (1.96 g/kg DM) content than other browse fruits. Fruits form V.karroo had higher Mg (4.75 g/kg DM), K (11.50 g/kg DM) and Na 3888 g/kg DM) content compared to other browse species. Fruits from V. Karroo showed significantly higher micro mineral content compared to other species. In terms of dry matter degradability (DMD), incubation time had an apparent effect on degradability of browse fruits except at 4 hours. The DM degradability increased with the increase of time and after 48 hours DMD was found to be satisfactory since it was above the prescribed 40 to 50 percent. However, the presence of condensed tannins had an effect on ruminal degradability of browse fruits. It was concluded that browse fruits have the potential to be used as protein supplements during the dry season since they contain moderate levels of crude protein. However, caution should be taken when feeding these browse fruits since they contain condensed tannins that affect rumen degradability. , Thesis (MSc) (Chemistry) -- University of Fort Hare, 2021
Full Text:
Date Issued: 2020-01

Integration of nanostructured metal sulfides into titanium (iv) oxide for high performance dye sensitized solar cell

Authors: Agoro, Adedoyin Mojeed
Date: 2020-01
Subjects: Nanostructured materials , Sulfur compounds
Language: English
Type: Doctoral theses , text
Identifier: http://hdl.handle.net/10353/21523 , vital:48857
Description: The work in this thesis describes synthesis, characterization and integration of nanostructured metal sulfides into titanium (IV) oxide for high performance dye sensitized solar cell. The synthesised single source precursors were evaluated using TGA, FTIR, , UV-Vis, PL,1H and 13CNMR, SEM, EDS, HRTEM, XRD, AFM, Raman, I-V, CV, Bode plot and EIS. TGA revealed the thermal degradation and quantified the mass percentage of metal sulphides as 33percent, 45percent and 27percent for CuS, PbS and SnS nanoparticles, respectively. FTIR analysis showed bands at 1580-1450 cm-1, and 1060-940 cm-1 tentatively assigned to C-N and C-S stretching frequencies correspondingly. The (M-S) stretching was observed at 577-406 cm-1 for the complexes using bis(N-di-isopropyl-N-octyldithiocarbamato) as primary ligands. IR spectra of bis(N-1,4-phenyl-N-(4-morpholinedithiocarbamato) as secondary ligands suggested the presence of (C-N) vibrations at 1508-1513 cm-1 for the complexes and 1507-1584 cm-1 for the ligands. The bands in the region of 973-1030 cm-1 were assigned to the complexes and 974- 983 cm-1 were attributed to the ligands, whereas vibration frequencies at 416-625 cm-1 were Nelson's Choice were included in these preliminary variety trials (PVTs) as checks. Twenty-five hybrids expressing high values for the Smith – Hazel selection index were identified across sites over years. Among those hybrids were two checks, namely Q16 (PAN5Q649R) and Q33 (Phb31MO7BR). The top five high – yielding hybrids selected based on the selection index were considered to be the most productive, stable and adaptable based on the GGE biplot and AMMI stability values. None of these single cross hybrids over yielded the best hybrid check (Q16) in the current study. A high potential environment, Centane, was the ideal environments for evaluating genotypes in the present study. The studies showed inbred lines L22, L23, L26, L28, L25, L29 and L31 to be low N stress tolerant at 0 kg N ha-1 based on the low N stress tolerance indices under glasshouse and the field conditions; they were also among the top ten grain-yielders under field conditions at 0 kg N ha-1. Also, in the NUE study, they were found to be among the top ten most N-efficient inbred lines under low N soils, under 30 kg N ha-1, and were among the top twenty-four inbred lines with high NUE values across the N levels in the study. Inbred lines L29 and L22 also produced testcross hybrids that were among the top twenty based on GY under 0 kg N ha-1. The testcross hybrids produced from these inbred lines were also among the top twenty-five with outstanding SCA effects for GY. These inbred lines were also parental lines of some of the top twenty- five best hybrids selected based on the Smith – Hazel selection index in the PVT study. Inbred lines L22, L23, L26, L28, L25, L29 and L31 can therefore further be evaluated and used as sources of N-tolerance genes in QPM breeding programs. tentatively assigned to M-S bond in the complexes. UV-Vis spectroscopy analysis for the complexes and from primary and secondary ligands are between within the range of 338 – 340 nm. PL studies of the primary ligands with metal complexes indicated emissions at 464 nm, 462 nm, 462 nm for Pb(II) and Sn(II), and Cu(II). The presence of secondary ligands was revealed by the absorption peaks at 455, 456 and 457 nm, exhibiting both the signals and chemical constituents of the respective ligands and their corresponding complexes. The electrochemistry in chapters 3 and 4 reveals that phase angle in the Bode plots changes with frequencies for Sn(II) complexes at 58, 57 and 8 respectively. Bode plots showed remarkable electronics of Cu(II) and Pb(II) complex interfaces. The CV curves exhibit two kinds of redox peaks indicating reduction at the negative potentials and oxidation at the positive potentials. The EIS, electrodes produced Rct for Pb(II), Cu(II) and Sn(II) electrodes in chapter 3. Moreover The EIS revealed that Sn(II) sensitizer displaced a stronger chemical capacitance and improved efficiency which could lead to better electron lifetime yield. The obtained CV exhibited anodic and cathodic peaks for Pb(II), connoting a reduction in Pb2+ and oxidation in Pb2-. Bode plot phase angle displayed Sn(II) and Pb(II) with maxima phase, indicating the presence of time constants of the electrode processes in Bis(N-1,4-Phenyl-N-Morhpo-dithiocarbamato bis(Mo/1,4-PHDTC) complexes. From the results in chapter 4, the XRD patterns exhibited good crystalline nature of CuS as a result of sharp and strong diffraction peaks obtained. There are eight peaks of 2θ angle between 26° and 79° relating to orthorhombic structure of SnS. While PbS has a cubic structure with polycrystalline nature, PbS/HDA and PbS both correspond to their crystalline planes of (200), (111), (220), (311), (222), (400), (331), (420) and (422) affirming to PbS QDs structure. SnS/HDA and SnS photosensitizers displayed eleven peaks between the values of 27.02° to 66.05° for SnS/HDA and 26.03° to 66.04° for SnS, in confirming the orthorhombic structure. SEM analysis revealed hexagonal structure for CuS, while PbS and SnS exhibited mesoporous nanostructures with spherical nanoparticles. HRTEM images indicated spherical nano-particles with particle sizes in the range of 3.14 - 44.39 nm. The outcome of HRTEM analysis revealed crystallite sizes varying as 10.90 – 11.57 nm, 3.14 – 5.95 nm and 14.96 – 44.39 nm for the CuS, PbS and SnS, originated from the primary ligands. HRTEM images originating from the Bis(N-1,4-Phenyl-N-Morhpo-dithiocarbamato bis(Mo/1,4-PHDTC) complexes indicated spherical nano-particles with particle sizes of 3.14 - 44.39 nm. Raman images in chapter 5 revealed the presence of Raman active modes of E2g 66 cm-1 and 304, cm-1 and E1g 627 cm-1 and 706 cm-1 for CuS, the active modes of TO 65 cm-1 and 2LO 626 cm-1 for PbS, active modes of B1g 69 cm-1 for SnS and 266 cm-1 for Ag. From the AFM results in chapter 5, CuS photosensitizer displayed a smooth surface and particle estimated to be 0.50 μm and height profile of 12percent. The PbS photosensitizer exhibited particle size of 1.82 μm and 0.654 μm for PbS/HDA, depicting a regular crystal growth rate. The size distribution of SnS nanoparticle at 357 nm connotes smooth surface and good compactness on the substrate. However, SnS/HDA at 122 nm displayed shape and size of non-symmetrical particles. AFM analysis in chapter 8 revealed good size roughness for CuS film. PbS exhibited particle size of 365 nm and size height of 18percent as the smoothest film, while PbS/HDA revealed 1.22 um size with 9percent size height. The evaluated particle sizes varied as 0.11- 1.18 um for SnS/HDA and 0.054 – 0.54 um for SnS films grown at 360 ℃ with size height of 16.8 and 8.4percent. The I-V efficiency obtained indicated that the CuS exhibited a much better efficiency in the QDSCs with higher Voc and the highest η being 2.85percent compared to CuS/HDA and Cu(II). High JSC of 11 mA/cm has been observed in the PbS/HDA QDSSCs, compared to the PbS and Pb(II) cells. The SnS/HDA exhibited a better performance compared to SnS and Sn(II) sensitizers due to the presence of HDA capping agent. , Thesis (MSc) -- Faculty of Science and Agriculture, 2020
Full Text:
Date Issued: 2020-01

Investigating communal farmer’s perceptions on production practices and evaluating pre-slaughter responsiveness of extensively reared Boran and Nguni steers

Authors: Guzi, Anelisa https://orcid.org/0000-0001-5568-3396
Date: 2020-01
Subjects: Boran cattle , Nguni cattle , Cattle breeds
Language: English
Type: Master's theses , text
Identifier: http://hdl.handle.net/10353/22721 , vital:52672
Description: This study's overall objective was to investigate communal farmers' perceptions on production practices and evaluate pre-slaughter responsiveness of extensively reared Boran and Nguni steers. On objective one farmers’ knowledge and perceptions on cattle breeds, management, and marketing channels in selected villages of Alice, Eastern Cape, South Africa were evaluated. Interviews were conducted using a structured questionnaire divided into demographic information and relevant cattle production practices, following a snowball technique to select 101 cattle-keeping households from Gaga, Ntselamanzi, and Ncerha villages. Most of the interviewed cattle farmers were males (65percent), in the age range of 40-60 years, with a primary-matric educational level. Among others, they highlighted financial security (47percent) and traditional ceremonies (26percent) as the reasons for keeping cattle. Most dominant in their herds were the Boran (49percent) and crossbreds (23percent) reared extensively with some supplementation (nutritional and medicinal). Their breed selection was based on disease and tick tolerance, temperament, and product (milk and meat) quality. It was noted that most of the interviewed cattle owners have the basic knowledge of good management practices, breed differences, and marketing chains. They related to low productivity to diseases, lack of knowledge, and poor resources. On the second objective pre-slaughter blood-based stress indicators and their subsequent effects were evaluated on beef quality of extensively reared Nguni and Boran steers . Twenty steers (10 Nguni and 10 Boran) aged 18 months were divided into two groups (with 5 of each breed per group) and transported from the University of Fort Hare Honeydale farm to the East London abattoir in the morning and afternoon trips. Upon arrival at the abattoir, the steers were held in lairage units for 24 hours (group 1) and 16 hours (group 2) until slaughter. Blood samples were drawn using a needle and vacutainer tubes from each steer's jugular vein at the farm before transportation, upon arrival at the abattoir, and during slaughter to perform cortisol, glucose, and routine haematological analysis. M. longissimus dorsi samples were harvested on the left side of each carcass to measure the meat quality attributes. Interactions between the observed production-stage activities, breeds, and physiological changes of these steers were recognized; with cortisol and glucose increasing (P ≤ 0.05) during transportation (4.15±0.46 ng/mL and 5.35±0.46nmol/L respectively) and also with farm group 1 showing higher cortisol (42.62±14.47 ng/mL) than the second group. Furthermore, all steers that were in slaughter group 1 showed less cortisol (101.49±14.47 ng/mL) and glucose (6.50±14.47 nmol/L) levels than those in group 2. In addition, Boran steers had higher packed cell volume, erythrocyte count, and haemoglobin values (33.27±0.54 percent, 7.66±0.19 106 μL, and 11.15±0.16 g/dl respectively) compared to Nguni steers in all production-stages. Later in the experiment, the effect of breed type, production stage activities (farm handling, transportation, and lairage duration), and stress responsiveness on some meat quality parameters (pH, lightness (L*), redness (a*), yellowness (b*), hue, Chroma, thawing and cooking loss, and tenderness) collected from the steers were measured. It was observed that the group lairaged for 16 hours produced the highest L* value (36.25±0.88) compared to those lairaged for 24 hours. As for the b* and hue of the meat, there were positive interactions between the breed type and the production stages (p<0.05). Lastly, cooking loss and tenderness were significantly affected by the breed type in all groups, with Nguni having the most tender meat (24.06±1.39 percent) and less cooking loss (16.92±1.33 percent) than Boran breeds. Therefore, the production stage conditions and breed type influenced some physiological stress-indicators and meat quality of Boran and Nguni steers raised on natural pastures. However, there were not many differences observed between the groups and breeds. , Thesis (MSc) -- Faculty of Science and Agriculture, 2020
Full Text:
Date Issued: 2020-01

Cultivation, nutritional and pharmacological evaluation of Celosia argentea (L) Kuntze: an endangered wild vegetable in the Eastern Cape Province of South Africa

Authors: Adegbaju, Oluwafunmilayo Dorcas
Date: 2019-09
Subjects: Celosia , Edible greens
Language: English
Type: Doctoral theses , text
Identifier: http://hdl.handle.net/10353/19806 , vital:43250
Description: Green leafy vegetables are important in human nutrition, but their cultivation is limited to a few staple ones. These vegetables possess high nutritious and therapeutic properties that could help in achieving nutritional security and alleviating the burden of some diseases. A typical example is Celosia argentea, which in South Africa, is little known and grossly under-utilized despite its numerous nutritional and pharmacological values. The present study investigated the cultivation, nutritional and pharmacological potentials of C. argentea at three stages of maturity of two trials. Evaluation of cultivation in the greenhouse towards possible domestication of C. argentea included seed viability test, seed germination under varying temperatures (5, 10, 15, 20 25 30, 35, 40°C), light conditions (continuous light, continuous darkness, alternating light and dark (12h light/12 dark photoperiod) and sowing depths (0, 1, 2, 3, 4 and 5cm). The nutritional evaluation assessed the proximal, mineral, vitamins and antinutrient content of the plant; while pharmacological potentials of C. argentea were evaluated by investigating the ultramorphology, phytochemical content, anti-oxidant, antimicrobial, toxicity and cell-based anti-inflammatory properties of the plant at different stages of growth. Germination experiment revealed that optimum seed germination requirements for C. argentea were 25°C, alternating light and dark regime and a sowing depth of 1cm. Microrphological assessment of C. argentea revealed that the leaves were amphistomatic; with the abaxial surface having higher stomata density. Characteristic, distinguishing protuberances were observed at the polar ends of the stomata on the adaxial surface of the plant epidermis, and the major elements on the foliar epidermis were beryllium, carbon, oxygen and potassium; while pigmentation and colouration, showing localization of bioactive compounds were mostly at the site where trichomes were abundant. Growth parameters and yield potential (plant height, stem girth, leaf area, number of leaves, number of branches, number of days to flowering, number of flowers as well as dry and fresh weight) of C. argentea showed that for agricultural practices on the field, increase in growth parameters should be expected around 4-5 weeks after transplanting while higher yield should be expected around 7-9 weeks after transplanting. The results encouraged cultivation during summer or late spring for best farm management. Proximal, mineral, vitamins and anti-nutrients content of C. argentea at three different maturity stages of two trials were performed using AOAC, ALASA and inductively coupled plasma-optical emission spectrometer techniques. Results revealed that the pre-flowering stage of growth had the highest ash (28.15± 0.10 percent) and crude protein (25.80 ± 0.20 percent) contents. While post-flowering stage had the highest carbohydrate (28.51± 0.20 percent and 36.16± 0.22 percent), crude fibre (33.41± 0.87 percent) and energy (435.28± 27.6 percent) with low fat and moisture (8.43± 0.15 percent and 6.35±0.09 percent) contents respectively; while no marked demarcation in most mineral contents in all the growth stages was observed. Zinc was highest at the flowering stage of growth, while vitamin contents decreased as the plant approached maturation. Antinutrients content of the plant was not dependent on growth stage. Total phenols, flavonoids and proanthocyanidin content of C. argentea were evaluated colourimetrically, while the antioxidant potency of the aqueous, acetone and methanolic extracts was measured using 2,2 diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), Ferric reducing antioxidant power (FRAP) and total antioxidant capacity (TAC) models. All the solvent extracts of the flowering stage had the highest total phenolic (80.75±4.21GAE/g), flavonoids (946.19±7.87QE/mg) and proanthocyanidin contents (100.90±1.29 CE/g); with the acetone extracts showing significantly higher phytochemical content. The flowering stage exhibited the best radical inhibitory activity, with the methanol extract having the highest scavenging power for ABTS and DPPH radicals, while acetone extract showed the highest inhibition against FRAP and highest total antioxidant capacity. The antimicrobial potential of the aqueous acetone and methanolic extracts of C. argentea evaluated using agar dilution method against six bacteria (Klebsiella pneumonia, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Bacillus cereus) and four fungal strains (Candida glabarata, Candida albicans and Penicillium aurantiogriseum and Penicillium chrysogenum) showed that Streptococcus pyrogenes and P. aeruginosa were susceptible to the methanol extracts of all the growing phases of both trials at 10 mg/mL; while Klebsiella pneumoniae was susceptible at 10 mg/mL to only the methanol post-flowering extracts of both trials. C. albicans and P. aurantiogriseum were highly susceptible to all the extracts. Possible toxicity evaluated using brine shrimp lethality assay and calculation of LC50 against brine shrimp nauplii revealed that C. argentea was not toxic at any stage of maturity at all concentrations evaluated. Anti-inflammatory activities and cytotoxicity of C. argentea extracts evaluated using RAW 264.7 macrophages and 3T3-L1 cell lines revealed that the acetone extract of the flowering stage had moderate anti-inflammatory activity with no significant toxicity against activated macrophages. Findings from this study indicate that C. argentea is a safe functional leafy vegetable of high nutritional and pharmacological importance which can easily be cultivated and domesticated in South Africa. This could significantly alleviate the burden of micronutrient deficiencies among pre-school children in rural communities. , Thesis (PhD) (Botany) -- University of Fort Hare, 2019
Full Text:
Date Issued: 2019-09

Studies on vine storage methods, planting techniques, paclobutrazol treatment, planting density and weevil management on sweetpotato (ipomoea batatas l.lam) cultivars promoted in South Africa

Authors: Hlerema, Igenicious Nicholas https://orcid.org/0000-0002-6111-404X
Date: 2019-09
Subjects: Sweet potatoes , Seed treatment
Language: English
Type: Doctoral theses , text
Identifier: http://hdl.handle.net/10353/21580 , vital:49336
Description: Sweetpotato (Ipomoea batatas L. LAM) is a major world staple food. It is a versatile, nutrient-rich crop well suited for production by emerging farmers, and thus a popular crop in subtropical parts of South Africa. The crop has several advantages such as producing more bioweight and nutrients per unit land area and per unit time than most other staple crops such as maize; adaptation to a broad range of agro-ecological conditions; and ability to compete and crowd out weeds, and affected by a relatively small number of pests and diseases. Root and vine yields achieved by emerging farmers are low and cultivation systems need to be optimized. The general objective of the research was to develop nursery practices that ensure a sustainable supply of sweetpotato planting materials and cultural practices that maximize yield, eating and nutritional quality of sweetpotato roots. The specific objectives were (i) to evaluate the effect of polyethylene and hessian bags on vine quality and vine survival period; (ii) to compare planting techniques and vine length; (iii) to determine the effect of paclobutrazol on storage root yield; and (iv) to evaluate the effect of Beauveria bassiana as biological control for sweetpotato weevil. The vine storage experiment aimed at identifying the best type of storage bags that keep the vines of “Bophelo”, an orange-fleshed sweetpotato cultivar in good quality for a longer period of time. The study involved two factors, viz storage bag type and storage period. The experiment tried to address (1) a sustainable seed system in sweetpotato and (2) production stimulated by cultural practises. Vines were stored in polyethylene bag without holes, polyethylene bag with 12 holes and dry hessian bag over 3, 6, 9, 12 and 15 days at an ambient temperature of 250C. The incremental cost-effectiveness ratio (ICER) was calculated to determine the cost-effectiveness of using the polyethylene bags with holes or without and the hessian bags. The results of the study showed that hessian bags store vines over a longer period (12 days) compared to the polyethylene bags without holes (6 days); however, hessian bags are more expensive. Polyethylene bags can still be used for transporting and storing vines if the farmer is within a short distance from the seed source and plants the vines within the 6 day period. Polyethylene bags with 12 holes are recommended since they allow maximum air circulation and extend storage period (9 days). Optimum planting techniques can help sweetpotato farmers to achieve optimal yields. Newly developed cultivars from the Agricultural Research Council have not been tested to determine the best planting techniques. A trial was conducted to investigate the effect of two planting orientations (horizontal and vertical) and different vine length (2, 3 and 4 subterranean nodes) of 3 released varieties, Blesbock, Bophelo and Ndou on storage root yield of sweetpotato. A factorial experiment was laid out in a randomised complete block design with three replications during two cropping seasons (2014/15 and 2015/16). The data collected in both experiments included total storage root yield, marketable storage root yield, and number of storage roots per size class. Significant differences were detected for the interaction of all factors on the number roots per size class, total storage root yield, and total average root weight. Vertical and horizontal planting per se showed no significance differences for all the sweetpotato root growth parameters such as total yield. However, the more the number of subterainian node the more yield we got for the commercial cultivar Blesbok. Paclobutrazol (PBZ) is a plant growth retardant hormone. This hormone might, therefore, be useful for sweetpotato growers to achieve higher plant populations per hectare because it would reduce the plant canopy. However, it should also be checked if the PBZ application does not affect nutrient content of roots and leaves, especially the beta-carotene content of the orange-fleshed cultivars. The objective of this study was, therefore, to determine the effect of PBZ on sweetpotato shoot growth, storage root yield and beta-carotene content of sweetpotato leaves and storage roots. The field trial was repeated over two seasons, namely 2014/15 and 2015/16 crop seasons. These field experiments were arranged as a split plot experiment. The main plots were allocated to four PBZ levels, laid-out as randomised complete block design, and treatment combinations of two cultivars (Bophelo and Blesbok) and two plants spacing (20 cm and 30 cm) were randomly allocated into the subplots. The PBZ levels applied were 0, 100, 200 and 300 mg of active ingredient per litre of water, sprayed 4 weeks after planting. Root yield and bioweight accumulation were recorded. In addition, a pot experiment was set up using cultivar Bophelo and 0 mg, 100 mg and 200 mg/l active ingredient of PBZ sprayed 4 weeks after planting. Leaf and root samples (150g and 400g of a composite sample respectively) were collected and analysed for total phenols, total flavonoids, vitamin C and beta-carotene. The field trial results revealed significant differences (P<0.05) in leaf and stem weight of the plants treated with different PBZ levels applied. The control (0 mg PBZ rate) had the highest leaf and stem weight. There were no significant differences in root yield among the PBZ levels. The results of leaf and root analysis for the Bophelo cultivar showed significant differences (P<0.05) in total phenols, total flavonoids, vitamin C and beta-carotene in leaf samples of the three levels of PBZ applied. The beta-carotene for the leaf increased at the 100 mg/l PBZ level. As the paclobutrazol level increased there was a reduction in the beta-carotene content for the roots from 18,91 to 13,97 to 10,77 mg/100g dry weight for 0 mg/l, 100 mg/l and 200mg/l, respectively. Application of PBZ to sweetpotato reduces the bioweight yield but does not have an effect on the root yield. Thus a higher plant density can be used to achieve higher yield and returns on investment. The leaves can be used as a relish and can be sold to supplement income. However, PBZ further reduces the beta-carotene content of the roots and is not recommended for use with orange-fleshed cultivars, where the objective is to enrich food with vitamin A. Sweetpotato weevils (Cylas puncticollis and C. formicarius) are notorious pests of sweetpotato. It causes severe losses in marketable root yield. The study tested the use of Beauveria bassiana (Balsamo Vuillemin) (Deuteromycota: Hyphomycetes) for controlling sweetpotato weevils. Experiments were conducted over two cropping seasons using four treatments: 1) dipping sweetpotato cuttings in solution of 1 g/litre B. bassiana before planting, 2) spraying with a registered chemical (Deltametrin) at 50 ml/100 litre of water starting 2 weeks after panting at biweekly basis for four months after planting, 3) spraying the leaves with B. bassiana (10 g/100 litre) starting 2 weeks on biweekly basis for four months after planting; and 4) control (sprayed with water). The research was arranged as split plot experiment, where the pest management treatments assigned to the main plots as per Latin square design and the three sweetpotato cultivars (Bophelo, Ndou and Blesbok) were randomly put in the subplot in each main plot. Spraying with B. bassiana significantly reduced the percentage of insect-damaged roots (9.95percent) compared to the control (22.48percent). Dipping sweetpotato cuttings in solution of 1 g/litre B. bassiana before planting did not significantly reduce the number of insect damaged roots (18.63percent insect damage). There was no significant difference between the chemical spray (8.2percent insect damage) and spraying with B. bassiana (9.95percent insect damage). The investigation indicated that B. bassiana can be considered as an alternative control method for the sweetpotato weevil. Use of biological control is less expensive and beneficial to reduce adverse effects on the environment and human health. , Thesis (PhD) -- Faculty of Science and Agriculture, 2019
Full Text:
Date Issued: 2019-09

Surveillance study on pathogenic Acinetobacter species in freshwater environment of the Amathole and Chris Hani District Municipalities, Eastern Cape, South Africa

Authors: Adewoyin, Mary Ayobami
Date: 2019-09
Subjects: Acinetobacter infections , Acinetobacter , Nosocomial infections
Language: English
Type: Doctoral theses , text
Identifier: http://hdl.handle.net/10353/19836 , vital:43257
Description: This study evaluates the occurrence of medically relevant Acinetobacter species in three rivers, namely; Keiskamma, Tyhume and Great Fish in the Eastern Cape Province, South Africa in one year sampling regime (April 2017 - March 2018). The physicochemical parameters (pH, temperature (TEM), electrical conductivity (EC), total dissolved solids (TDS), salinity (SAL), total suspended solids (TSS), turbidity (TBS), dissolved oxygen (DO) and biological oxygen demand (BOD)) of the water bodies were measured. The presumptive Acinetobacter species recovered from the freshwater resources were recorded and further confirmed using molecular techniques. Similarly, confirmed isolates were subjected to speciation using species-specific primer sets for A. baumannii and A. nosocomialis. Also, virulence genes namely; afa/draBC, epsA, fimH, OmpA, PAI, sfa/focDE, and traT in the two Acinetobacter species were also determined using molecular method. In addition, the antibiogram characteristics of A. baumannii and A. nosocomialis isolated from the water samples were determined using standard methods. The antibiotic susceptibility test was performed using a panel of 12 antibiotics belonging to the aminoglycosides (amikacin, AK and gentamicin, GM), β-lactam/β-lactamase-inhibitor combinations (piperacillin-tazobactam, PTZ), cephems (ceftazidime, CAZ, cefotaxime, CTX, and cefepime, CPM), carbapenems (imipenem, IMI and meropenem, MEM), fluoroquinolones (ciprofloxacin, CIP), folate pathway inhibitors (Trimethoprim/sulfamethoxazole, TS), lipopeptides (Polymyxin B, PB) and tetracyclines (tetracycline, TET). Similarly, antibiotic resistance genes (ARGs) present in the Acinetobacter isolates were investigated including aminoglycoside resistance genes (aacC2, aphA1 and aphA2), β-lactamases resistance genes (blaTEM, blaSHV, blaOXA-1-like, blaCTX-M(GROUP 1), blaCTX-M(GROUP 2), blaCTX-M(GROUP 9), blaVEB, blaGES, blaPER, blaCTX-M-8/-25, blaOXA-48-like, blaVIM, blaIMP and blaKPC), fluoroquinolones resistance genes (qnrA, qnrB, qnrC, qnrD and qnrS), sulfonamide resistance genes (sul1 and sul2), and tetracycline resistance genes (tetA, tetB, tetC, tetM, tetL and tetO). The pH, EC, TDS, SAL, TEMP, TSS, TBS, DO, and BOD for Tyhume River ranged as follows: 7.2-7.7, 125-141 μS/cm, 62-71mg/L, 0.06- 0.07 PSU, 11.3-20.2oC, 30.0-89.6 mg/L, 35.0-96.0 NTU, 8.2-9.8 mg/L, 2.0-4.2 mg/L, while for Great Fish River, the parameters were 8.0-8.2, 274-369 μS/cm, 137-184mg/L, 0.13-0.18PSU, 12.7-22.3oC, 44.3-99.4 mg/L, 48.0-214.0 NTU, 7.8-9.9 mg/L, 3.1- 4.9 mg/L, and at Keiskamma River they were 7.5-7.9, 153.2-285.0 μS/cm, 86-143 mg/L, 0.07-0.14 PSU, 11.0-21.4oC, 27.0- 55.6 mg/L, 31-61 NTU, 8.3-9.8 mg/L, 3.0-6.0 mg/L. A total of 1107 presumptive Acinetobacter spp. were recovered from the rivers sampled of which 428, 370 and 309 isolates were recovered from Tyhume, Great Fish and Keiskamma rivers respectively. However, only 844 was confirmed positive for the genus Acinetobacter and are recovered in the proportions 285 (77 percent), 219 (70.9 percent) and 340 (79 percent) from Great Fish, Keiskemma and Tyhume rivers respectively. Our finding revealed that 410 (48.58 percent) and 23 (2.7 percent) of the isolates were confirmed to be A. baumannii and A. nosocomalis respectively. Also, 308 (75.12 percent percent) A. baumannii and 3 (13.04 percent) A. nosocomialis isolates exhibited one or more virulence genes out of the seven tested, whereas 102 (24.88 percent) and 20 (86.95 percent) of the A. baumannii and A. nosocomialis isolates did not harbour any virulence gene. Additionally, OmpA was the most prevalent (p<0.05) virulence gene found in A. baumannii with 69 (45.10 percent), 52 (50.98 percent) and 77 (49.68 percent) isolates from Great Fish, Keiskamma and Tyhume rivers respectively. The rates of susceptibilities of A. baumannii and A. nosocomialis to the antibiotics followed the order; Piperacillin-tazobactam (72.8 percent ; 73.9 percent), Ceftazidime (70.5 percent ; 91.3 percent), Cefotaxime (16.8 percent ; 17.4 percent), Cefepime (88.5 percent ; 95.7 percent), Imipenem (95.9 percent ; 100 percent ), Meropenem (92.7 percent ; 91.3 percent), Amikacin (97.6 percent ; 91.3 percent), Gentamicin (89.8 percent ; 87 percent), Polymyxin B (84.4 percent ; 91.3 percent), Tetracycline (74.7 percent ; 78.3 percent), Ciprofloxacin (75.9 percent ; 78.3 percent) and Trimethoprim/sulfamethoxazole (74.0 percent ; 73.9 percent) respectively. Both A. baumannii and A. nosocomialis were highly susceptible to all the antimicrobials tested except cefotaxime where 64 percent and 78 percent intermediate responses were observed in the species. At least 10 isolates of A. baumannii were resistant against each of the antibiotics used. The modal multiple antibiotics resistance phenotypes (MARPs) for Acinetobacter spp. was MARP 3 (29.87 percent) and the least was MARP 10 and 11 (2.6 percent each). The antimicrobial resistance index (ARI) was higher at two sampling sites KE2 (0.33) and TY1 (0.22). Similarly, MARI showed that sampling sites KE2 was a hotspot for multidrug-resistant Acinetobacter spp. Of the five classes of ARGs studied, there was a widespread of β-lactamases (blaTEM) in the two Acinetobacter species, followed by sul2, which were detected in 67 (63.2 percent) and 44 (49.4 percent) isolates respectively, across the rivers studied. We conclude that aquatic resources of the study community are important reservoirs of pathogenic Acinetobacter species and antibiotic resistance determinants. The occurrence of clinically-important Acinetobacter species suggests possible contamination of these selected rivers which are consumed by humans and livestock, as well as being used for irrigation system, and this constitutes a risk to public health. It also shows that A. baumannii and A. nosocomialis can thrive in the aquatic environment. This study suggests that direct utilization of water from these sources for domestic and other purposes without any form of pre-treatment should be avoided. It is, therefore, necessary for regulatory authorities to monitor the release of domestic and industrial wastewater into these water bodies in order to prevent outbreaks of epidemics. , Thesis (PhD) (Microbiology) -- University of Fort Hare, 2019
Full Text:
Date Issued: 2019-09

Profitability and technical efficiency of small-scale organic crop farmers’ in the Eastern Cape Province of South Africa

Authors: Eyinade, Gabriel A https://orcid.org/0000-0001-8851-7255
Date: 2019-08
Subjects: Organic farming , Farms, Small
Language: English
Type: Doctoral theses , text
Identifier: http://hdl.handle.net/10353/23633 , vital:58229
Description: Organic farming is growing gradually in South Africa. Its contribution to economic growth and poverty mitigation is notably in the pastoral areas in terms of providing adequate and affordable food for the incessantly growing population. Organic farming is also known for provision of employment and source of livelihoods for the rural populace as well as supply of raw materials to the country’s agro-allied industrial sector. For the purposes of this research, focus was only on profitability and technical efficiency because it is an essential subject in developing agriculture where resources are limited, but high population growth is very common. As a result, increased output will rely more on efficiency enhancements which will further intensify farmers’ income. As such, evaluating the extent for such efficiency enhancements within the system is a crucial prerequisite. The objective of the study was to assess the profitability and technical efficiency; and to identify socio-economic, institutional and farm characteristics that influence profitability and the technical efficiency of the small-scale organic crop farmers in the Buffalo City Metropolitan Municipality (BCMM). A purposive sampling technique was used to collect primary data from 160 small-scale organic crop farmers in BCMM. The gross margin estimation was used to estimate profitability, while multivariate Ordinary Least Square (OLS) was used to assess socio-demographic factors influencing profitability. The stochastic frontier model was used to determine the level of technical efficiency as well as the determinants of technical inefficiency of the farmers. The results of the gross margin estimation show that the small-scale organic maize (GM= R392 417.00) and cabbage (R196 489.00) farms were profitable. Similarly, the results of the OLS showed that one out of the eight variables namely, farming experience influences organic maize producers’ profitability, while factors such as gender, household size, and educational level emerged as the major significant factors influencing organic cabbage producers’ profitability. The stochastic results revealed that small-scale organic crop farmers in the study area are technically efficient at 86percent in maize production and 93percent in cabbage production respectively; and experienced unity return to scale (1.0) in maize and increasing return to scale (1.2) in cabbage. The results suggested that an increase in the use of input, would also intensify their productivity and efficiency. The results from the inefficiecncy model of the stochastic frontier further show that age and farming experience are the major determinants of organic maize producers’ technical inefficiency, while, factors such as age, years of schooling, farming experience, and household size were the significant determinants of organic cabbage producers’ technical inefficiency. To enhance the farming potential of these farmers, it is recommended that government and other several stakeholders such as researchers, entrepreneurs should invest more in organic crop farms since it is profitable and efficient in improving farmers’ livelihoods. There is also need for government to organise on-going workshops and extension training through the help of extension officers on how farmers can improve their production which will further enhance their income. , Thesis (PhD) -- Faculty of Science and Agriculture, 2019
Full Text:
Date Issued: 2019-08

A comparative analysis of mobile application development frameworks: A case study of mobile application development for water usage management in Alice and Fort Beaufort communities

Authors: Manu, Kwabena
Date: 2019
Subjects: Mobile communication systems Cell phones Cloud computing
Language: English
Type: Thesis , Masters , MSc. (Computer Science)
Identifier: http://hdl.handle.net/10353/14130 , vital:39853
Description: Mobile phones have become an integral part of standard of living. Users and customers expect sensible and very useful applications in less time. In this competitive market, it is an enormous challenge to develop high performance mobile applications that might meet the expectations of end users. Despite the fact that development of new applications for each mobile operating system in short time is fairly an issue, mobile operating systems vendors are giving their best available resources for creating applications in additional convenient ways. These days, there is a common tendency to look for less complex and quicker solutions that could be used in the process of software development. Developers of a new mobile application have to undertake variety of selections and decisions, including the target platform as well as the development technology to utilize. Mobile application development frameworks contribute in solving this problem. Several frameworks have emerged, which we classify and evaluate their appropriateness. In order to compare existing development frameworks solutions in this research, we compiled a set of criteria to assess mobile application development approaches. In view on these criteria, we evaluated five frameworks that is, PhoneGap, Xamarin, App Inventor, Sencha Touch and DragonRad. For proof of concepts, the chosen framework from the five evaluated mobile development frameworks was used to develop application for water usage management. The research will equip mobile application developers to gain more insight into mobile development frameworks available, therefore helping them to choose the most appropriate framework for their project.
Full Text:
Date Issued: 2019

A Model for Intrusion Detection in IoT using Machine Learning

Authors: Nkala, Junior Ruddy
Date: 2019
Subjects: Internet of things
Language: English
Type: Thesis , Masters , MSc (Computer Science )
Identifier: http://hdl.handle.net/10353/17180 , vital:40863
Description: The Internet of Things is an open and comprehensive global network of intelligent objects that have the capacity to auto-organize, share information, data and resources. There are currently over a billion devices connected to the Internet, and this number increases by the day. While these devices make our life easier, safer and healthier, they are expanding the number of attack targets vulnerable to cyber-attacks from potential hackers and malicious software. Therefore, protecting these devices from adversaries and unauthorized access and modification is very important. The purpose of this study is to develop a secure lightweight intrusion and anomaly detection model for IoT to help detect threats in the environment. We propose the use of data mining and machine learning algorithms as a classification technique for detecting abnormal or malicious traffic transmitted between devices due to potential attacks such as DoS, Man-In-Middle and Flooding attacks at the application level. This study makes use of two robust machine learning algorithms, namely the C4.5 Decision Trees and K-means clustering to develop an anomaly detection model. MATLAB Math Simulator was used for implementation. The study conducts a series of experiments in detecting abnormal data and normal data in a dataset that contains gas concentration readings from a number of sensors deployed in an Italian city over a year. Thereafter we examined the classification performance in terms of accuracy of our proposed anomaly detection model. Results drawn from the experiments conducted indicate that the size of the training sample improves classification ability of the proposed model. Our findings noted that the choice of discretization algorithm does matter in the quest for optimal classification performance. The proposed model proved accurate in detecting anomalies in IoT, and classifying between normal and abnormal data. The proposed model has a classification accuracy of 96.51% which proved to be higher compared to other algorithms such as the Naïve Bayes. The model proved to be lightweight and efficient in-terms of being faster at training and testing as compared to Artificial Neural Networks. The conclusions drawn from this research are a perspective from a novice machine learning researcher with valuable recommendations that ensure optimal classification of normal and abnormal IoT data.
Full Text:
Date Issued: 2019

Aeolian processes and landforms at Mesrug on sub-Antarctic Marion Island

Authors: Nguna, Abuyiselwe Athandile
Date: 2019
Subjects: Eolian processes Sediments (Geology)
Language: English
Type: Thesis , Masters , MSc
Identifier: http://hdl.handle.net/10353/17095 , vital:40848
Description: Recent observations have recognised the increasing role of aeolian processes as a geomorphic agent on sub-Antarctic Marion Island. This study presents the first long-term data on aeolian processes and dynamics at Mesrug (46° 56’ 41”S; 37° 49’ 59”E) on subAntarctic Marion Island. An intensive and high-resolution (five-minute interval) environmental monitoring campaign was initiated using Pace Scientific XR5 data loggers while aeolian transported sediments were collected using Big Spring Number Eight (BSNE) sediment traps at four different heights above the ground. The aeolian features at Mesrug is identified as mega-ripples and is essentially an erosional feature, while annual sediment flux at 0.05 m height were calculated as 2.29 kg cm-2 y -1 . Spatial data based on a two-year survey showed that the entire surface of the study area have lowered by deflation while the ripples shifted slightly eastward (down-wind). Furthermore, the site lost 3.4 m3 of sediment between these two surveys with an average of 0.75 cm per 1 m2 across the site which has an area of 454 m2 . The study suggest that the relatively large particle size of surface sediments on Marion Island is a major contributor to the low annual aeolian sediment flux. From the AWS data it is clear that high wind speeds are frequent at Mesrug and the high wind speeds facilitating sediment movement. Sediment supply is the limiting factor of aeolian sediment transport, but even though the perennial wetness experienced on the island is not a major limiting factor to sediment flux, it may influence rate of movement. The predominant wind direction at the study site is from the south-west but maximum wind velocities are from the north-west. The data from the wind-aspirated BSNE sediment traps, indicate that sediment movement occurs closest to the surface and weight of sediment moved as well as size of particles decreases vertically in the air column. It seems that the upper limit of aeolian sediment transport at Mesrug is 0.8 m above the ground and saltation of particles is the dominant aeolian transport mechanism. Sediment movement occur in near gale to gale force winds and horizontal precipitation. This is mainly associated with strong north-westerly winds which are linked to a frontal system from a mid-latitudinal cyclone that has a strong meridional component or is a cut of low pressure. The data suggest that the climate change implication of a reduction in the westerly component of wind could reduce wind speeds and this could influence the magnitude and frequency of aeolian sediment transport on Marion Island in the future
Full Text:
Date Issued: 2019

Amaranth (Amaranthus cruentus) growth and nutritional contents as affected by nitrogen and potassium fertiliser and plant density

Authors: Mamvura, Luckmore
Date: 2019
Subjects: Weeds -- Control -- Management
Language: English
Type: Thesis , Masters , MSc
Identifier: http://hdl.handle.net/10353/17249 , vital:40869
Description: The research was conducted to determine the response of amaranth growth and development to different rates of nitrogen and potassium fertilizer, the effect of plant density on herbage yield and weed management, effect of leaf age and stems on nutritional value of amaranths. The research was conducted at the University of Fort Hare Research Farm and University of Fort Hare glasshouse. For the fertilizer trial, a 4 x 3 factorial experiment: nitrogen at four levels (50kg/ha; 100kg/ha; 150kg/ha; 200kg/ha) and potassium at three levels (50kg/ha; 75kg/ha; 100kg/ha) was applied. Phosphorus was applied at 50kg/ha. The experiment was laid as randomised complete block design (RCBD) with 4 blocks (replication). The results showed that application of nitrogen and potassium treatments significantly (P < 0.05) increased plant height, stem girth and number of leaves per plant which in turn increased the crop economic leaf vegetative yield. The results also showed that at high rates of nitrogen and potassium, high vegetative yields were achieved in most cases. There was no interaction (P < 0.05) between nitrogen and potassium. Second experiment, the twelve treatments used in fertilizer trial were imposed under four different amaranth plant densities (1 200 000, 1400 000, 1600 000 and 1800 000 pph) at field level to find out growth and development performance of amaranth. In addition, at the same time investigating the effectiveness of plant density on weeds management using split plot design. The different planting densities were allocated to the main plots laid-out in RCBD. The results showed that there was no significant difference (P < 0.05) on the number of weeds under four plant densities. The results showed that different plant densities did not prevent weeds germination but the amaranths tolerate the negative effects of weeds. The nutritional analysis results showed that amaranth synthesised close to above recommended nutritional level despite different treatments applied. The third experiment: stems, lower and upper leaves were harvested separately and their nutritional composition was analysed. The results showed that the nutritional composition of stems, lower leaves and upper leaves were significantly different (P < 0.05) in most cases. Lower leaves dominated nutritional content for: crude protein crude fibre, carbohydrates, and calcium. The stems recorded least nutritional content on crude protein, crude fat, carbohydrates, calcium, potassium and sodium
Full Text:
Date Issued: 2019

An Assessment of the Environmental Impacts of Urban Sprawl in Buffalo City Metropolitan Municipality, Eastern Cape Province

Authors: Matiza, Collins
Date: 2019
Subjects: Cities and towns -- Growth -- Environmental aspects City planning
Language: English
Type: Thesis , Masters , MSc
Identifier: http://hdl.handle.net/10353/17260 , vital:40870
Description: Large industrial and residential developments near towns and along highways associated with public policies have transformed the pattern of development over the recent years, creating a new urbanisation phenomenon; urban sprawl. Indiscriminate population densities, discontinuous and fragmented settlements, largely define urban sprawl. The progression of urban sprawl can be described by transformation in pattern over time, like proportional increase in built-up surface to population leading to rapid urban spatial expansion. Stemming an understanding from the processes, causes and patterns of urban sprawl, the consequences of sprawl on land and vegetation can be analysed. Environmental impacts to both the rural and urban population emanate from such instances, creating an excessive liability to the government. With attention to this and recognising the lack of discussion on the matter, the research deliberates some of the impacts observed in Buffalo City Metropolitan Municipality, Eastern Cape, South Africa. The study makes use of Geographic Information Systems and Remote Sensing with the assistance of landscape metrics. The influence of urban sprawl in this municipality has revealed impacts on vegetation, green areas and land in general. The results disclose that urban sprawl is a multidimensional phenomenon that is better explained using various methods (indices). Buffalo City Metropolitan municipality is located in Eastern Cape amidst the thicket ecosystem, the municipality has grown and expanded over the recent past. The study spread over an 18-year period from 1994- 2012. Based on field surveys and SPOT imagery, built-up areas of BCMM was extracted for different periods. Data used for the study are census data for BCMM, 1994, 2000, 2006 and 2012 SPOT images, images of BCMM acquired from Google earth 2018. The rate of transformation of the area was calculated and it was higher compared to that of population growth. Based on this data urban growth are analysed with the assistance of landscape metrics that include Shannon entropy. The outcomes confirm that this metropolitan municipality has experienced sprawl and sprawl has done so at cumulative rate.
Full Text:
Date Issued: 2019

Analyses of Retail and Transport Geography of Liquefied Petroleum Products in Ibadan metropolis, Nigeria

Authors: Ajayi, Adeyinka Peter
Date: 2019
Subjects: Petroleum products
Language: English
Type: Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10353/19065 , vital:40090
Description: This study analyzed the effects that spatial arrangement of petroleum products retail outlets and the supply chain management techniques employed for products distribution (for both intra city and intercity shipments) have on the retailing dynamism of petroleum products within built environment and peripherals of Ibadan metropolis over the years. Specifically, the study investigated the differentials in the spatial configurations of petroleum products retail outlets between the core and periurban zones of the metropolis. An attempt was made to determine the explanatory variables that influence the spatial distributional decisions of petroleum products retail outlets in the metropolis. The study equally examined how the supply chain management (SCM) techniques by the different categories of the retail outlet owners influence the efficient and cost effective distribution of petroleum products. Lastly an attempt was made to analyze the relationship between the socio-economic attributes of the haulers and the achievement of compliance to the HSE stipulations guiding the conveyance of petroleum products. The theoretical underpinnings for the research were a derivative of the amalgamation of normative and psychological theories from geography, psychology, SCM and retailing science. Specifically, Expectation Disconfirmation Theory (EDT), Distributive Justice, Central Place Theory (CPT) Theories of Urban Impact (TUI) and Theory of Constraint (ToC) were the theories utilized in the study. For the achievement of the first objective which was to investigate the possible differential in the compliance rate between spatial pattern of fuel retail outlets in the core and peripheral zones of Ibadan metropolis, the first hypothesis of the study (which examined if there was no significant difference in the rate of compliance to the planning authority stipulations guiding the location pattern of petroleum product retail outlets between those located in the built up and xxiv peripheral zones of the city), was tested through the use of buffering and proximity analyses in the ArcMap environment of ArcGIS 10.1, while inferential statistical tool of an independent-samples t-test was conducted to compare the rate of compliance to the stipulations guiding the locations of these outlets in both the core and the peripheral zones. The result from the GIS analysis indicated that 33 (15.56%) out of the 220 outlets in the core zone of the metropolis complied with the planning stipulations guiding the location of fuel retail outlets. For the peripheral zone, out of the 220 fuel retail outlets 24 (10.90%) complied with the stipulations. The result from the t- test which was employed to test the hypothesis indicated that no significant difference existed in the rate of compliance t (263) =-2.66, p = 0.08 between fuel retail outlets in the core zone (M=3.9, SD=1.4) and peripheral zone (M=4.5, SD=1.79). The alternate hypothesis which stated that ―no significant difference existed in the compliance rate between fuel retail outlets located in the two zones‖ is accepted. For the achievement of the second objective of the study which was to analyze the factors which determine the location of fuel retail outlets both in the core and peripheral zones of Ibadan metropolis. All the managers/owners of the 432 fuel retail outlets in the metropolis were sampled out of which 256 questionnaires were retrieved for the purpose of this analysis. The breakdown of the socio-economic characteristics of the sampled respondents showed that the gender distribution showed that 194 (75.78%) of the respondents were males, while 64 (24.22 %) were females. The average age of the sampled population was 33.70 years. The mixed method was employed for the achievement of the second objective of this study. Logistic Regression Model (LRM) was employed to test the hypothesis and the result revealed that the inclusion of the independent variables in the model increased the overall level of it accuracy. The overall significance revealed that the Model Chi- xxv Square, derived from the likelihood fitted is also accurate (X2 = 43.47, df=5, p>.05). The model chi-square value of 43.47 (approximately 44% ) was significant. Thus, the indication is that the model has a good fit in predicting the possibility of a fuel retail outlet being located in the core or peripheral zone of the metropolis as determined by the explanatory variables (the independent variables accounted for about 44% of possible factors which determined whether a fuel retail outlets is located either within the core or peripheral zones of the metropolis. The remaining 56% are factors not considered in the study). The result gotten from the in depth interview sessions corroborated the findings from the tested hypothesis. The third objective was to examine the effects which the supply chain technique employed (either vertically integrated model or third-party arrangement) has on the achievement of efficient and effective distribution of the products. In order to achieve this objective, all the 389 registered members of Petroleum Tanker Drivers (PTD) association who are members of the PTD in the metropolis were sampled, 265 (around 70%) of the distributed questionnaires were retrieved and used for the analysis. In depth interview sessions were also conducted with three different managers of the three major conglomerates in the downstream sector of the Nigerian petroleum sector. The result of one-way between subjects (ANOVA) which was conducted to compare differences in the management and performances of haulage services outsourced to the 3PLS and those run under VIM showed that there was a significant effect of ownership type on management performance (F (2,262) = 60.26, p<.05). The null hypothesis was therefore rejected while the alternate hypothesis was accepted. The findings from the interview sessions posted similar results. The fourth and final objective was to analyze the effect that the socio-economic attributes of the participants (haulers and managers of retail outlets) involved in the distribution of xxvi petroleum products has on the safe, efficient and cost-effective distribution of product and this was done through the use of descriptive statistics, inferential statistics and incisive analysis of the interview sessions. A total number of 265 (70%) out of the 389 registered members of Petroleum Tanker Driver Association (PTDA) participated in the study. Multiple regression analysis (MRA) was used to test this hypothesis. The result from the statistical analysis show that the use of stimulant, work condition, marital status and educational attainment/literacy level have joint influence on compliance (R2 = 0.31, F (4,260) = 29.72, p<.05). On the basis of the foregoing, the hypothesis is thus accepted. The result from the interview sessions confirmed the existence of strong relationship between the explanatory variables and the hypothetical dependant variable. The study recommended a review of the planning processes guiding the establishment of fuel retail outlets. The study also advocated that retailers should endeavour to have stronger control over the supply chain of their products this could done by investing more in VIM rather than outsourcing such functions to 3PLs. This will help in better business performances. Government agencies in charge of monitoring drug abuse among haulers are advised to be more proactive by the duo of prevention and punishment strategies. This should include advocacy campaign against drug abuse. Different ranges of punishments should also be meted out for individual haulers found culpable.
Full Text:
Date Issued: 2019

Application of some missing data techniques in estimating missing data in high blood pressure covariates

Authors: Odeyemi, A. S
Date: 2019
Subjects: Missing observations (Statistics) Hypertension
Language: English
Type: Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10353/15189 , vital:40195
Description: Cases recorded with high blood pressure are a major concern in both public and private hospitals. Adequate provision of health information of patients relating to high blood pressure in Eastern Cape Hospitals hinges so much on the outcome of statistical analysis results. The usual statistical methodologies become inadequate in handling statistical analysis of data collected due to incomplete patients’ information stored in the hospital database. From time to time, new methods are developed to address the problem of missing data. High blood pressure is linked to a lot of diseases such hypertension, cardiovascular disease, kidney disease and stroke. In this study, we developed a new method for addressing the problem of missing data in assessing model used for estimating missing values in terms of minimum errors(using RMSE, MAE, and SE) and goodness-of-fits(using 2 R and adjusted 2 R ) of this model and P-value. . The study compared six different methods: Original data (OD), Listwise deletion (LD), Mean imputations (MEI), Mean above (MA), and Mean above below(MAB) and two steps nearest neighbour (2-NN).The comparison was performed using original data set, and missing values at 5%, 10%, 20%, 30% were simulated on Framingham risk scores under MCAR and MAR simulation on BMI values given some assumptions. Five performance indicators were used to describe the model minimum errors and goodness of fit for all the methods. The results showed that the 2-NN is the best replacement method at lower levels (5% and10%) of missing values while MA and MEI performed best at higher levels(15% and 20%) of missing values. All comparison was based on estimates closest to those of the original data where no value was missing. MAR results showed that 2-NN performed better than LD,MA,MAB, and MEI at 5%,10%, and 20% levels of missing data in terms of absolute difference in p-value to original data.
Full Text:
Date Issued: 2019

Assessment of phytochemical constituents, antioxidant properties and cytotoxicity potentials of Leonutis leonurus and Boophone disticha extracts used in the management of Alzheimer’s disease in Hogsback, Eastern Cape, South Africa

Authors: Tonisi, Sipho
Date: 2019
Subjects: Medicinal plants Alzheimer's disease
Language: English
Type: Thesis , Masters , MSc (Microbiology)
Identifier: http://hdl.handle.net/10353/14726 , vital:40067
Description: In this present study, the phytochemical compounds, antioxidant activities, and cytotoxicity potentials of solvent extracts (polar solvents) of Leonotis leonurus (L. leonurus) and Boophone disitcha (B. disticha) commonly used in the management of Alzheimer’s diseases in Hogsback, in the Eastern Cape, South Africa were investigated. The phytochemical compounds were determined by standard protocols of Folin–Ciocalteu method, aluminium chloride colorimetric method as well as Mayer’s and Wagner’s method. The antioxidant capabilities were assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydrogen peroxide, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and nitric oxide radical scavenging assays. The majority of extracts from both plant species exhibited free radical scavenging potential for oxidants they were tested against viz; DPPH, hydrogen peroxide, ABTS and nitric oxide. They further displayed good reducing potential against ferric iron. The results have shown a concentration-dependent dose of inhibition/scavenging activity (in DPPH, hydrogen peroxide, ABTS and nitric oxide assays) and reducing ability (in ferric reducing assay). However, leaf extracts of L. leonurus displayed ineffective scavenging activity against nitric oxide whereas extracts from L. leonurus flower and B. disticha bulb had higher scavenging potential against the production of nitric oxide radical. The GC-MS profiles of the plants extracts revealed the presence of numerous bioactive compounds that are known to possess excellent anti-inflammatory and most importantly antioxidant properties. Another interesting observation of GC-MS analysis data was the presence of compounds reported to inhibit Acetycholinesterase (AChE), which is a key enzyme targeted in the treatment of Alzheimers’ Disease (AD). The cytotoxicy tests for these extracts were carried out in order to assess the potentential detrimental effects on human health using Alamar Blue assay. It was noted that an increase in the extract concentration of both plant species resulted in a noticeable decline in cell population. These extracts were then declared xix to be quite toxic against HeLa (human cervix adenocarcinoma cells) cells as the cell viability in some extracts was quite low. Hence, toxicity testing of the studied plants’ extracts against normal cells is highly imperative in the future study. The results from this present study scientifically validated the use of the studied plants in folkoric medicine for the management of Alzheimer’s diseases.
Full Text:
Date Issued: 2019

Assessment of some bacteria species isolated from woodlands of Raymond Mhlaba Local Municipality for high activity laccase production

Authors: Gogotya, Asemahle
Date: 2019
Subjects: Laccase
Language: English
Type: Thesis , Masters , MSc (Microbiology)
Identifier: http://hdl.handle.net/10353/19098 , vital:39879
Description: The function of enzymes in keeping the earth clean is enormous; being executed in the biodegradation of different natural pollutants and biocatalysis of different responses by substituting the ecologically risky and harmful concoction impetuses offering a situation inviting option, laccases is an example of an enzyme described as it doesn’t produce harmful byproducts. Laccases are employed in several industrial processes that play a key responsibility in transformation of life and making the environment a better place. Bacteria have been described as best producers of laccases with a potential in the industrial scale processes. Laccase was produced from different bacterial isolates identified and named as Bacillus sp. strain GFN1 isolated from soil sample, Bacillus sp. strain GLN and Streptomyces sp. strain LAO both isolated from decaying wood samples in Raymond Mhlaba local municipality with accession numbers MK290988 to MK290990 respectively, as identified by partial sequencing, these were the best producers some of which were positive for Napthol and guaiacol; even upon quantitative screening they were better laccase producers. For quantitative laccase screening, 2,2'-azino-bis(3-ethylbenzothiazoline-6- sulphonic acid) was utilised as the substrate for laccase assays. These laccase producing bacteria were subjected to optimization of growth conditions using submerged fermentation which increased the activity of the produced laccase in great amounts. In optimizing basal medium growth conditions where laccase was harvested after every 72 hours where optimal activity was 16 obtained, studying several factors such as pH which turned out to be pH 5 for all isolates, effect of supplemented carbon and nitrogen sources with the be best being lactose and urea respectively with their effective concentrations using lignin as the main carbon and nitrogen source. Copper sulfate was used as the main inducer and the species preferred guaiacol and ferullic acid and the Fe2+ asthe best supplemented metal ion. The time course was done investigating parameters such as cell growth which was determined by observing the optical density, laccase activity, protein concentration and pH and the presented results suggested that when there was an increase in cell growth, enzyme activity decreased pH had no much effect on the enzyme production as it was almost stable all the time with protein concentration exhibiting no direct effect on enzyme activity also. Characterization of the crude enzyme was done to check the stability of the enzyme produced in various parameters. The enzymes produced by the different strains were thermophilic as they were able to withstand elevated temperatures between 90 and 100 C, with pH stability within an extensive variety of alkaline pH, typical of most bacterial laccases. Various metal ions affected the stability of the enzyme with CuSO4 increasing the stability of two of the bacterial enzyme and appeared to slightly decrease the stability of one enzyme. The studied inhibitors only decreased the stability on the enzyme and couldn’t completely inhibit the enzyme, and the enzymes showed specificity towards varying substrates. The studied bacterial laccases exhibit tremendous characteristics which are of great significance in the industries and will add to the novelty of bacterial laccases and their stability amongst the most studied fungal laccases.
Full Text:
Date Issued: 2019

Bioavailability of nutrients in a diet enriched with moringa oleifera lam. Leaves using wistar rats

Authors: Mhlomi, Yanga Nonelela
Date: 2019
Subjects: Moringa Medicinal plants
Language: English
Type: Thesis , Masters , MSc
Identifier: http://hdl.handle.net/10353/14594 , vital:40018
Description: This study investigated the nutritional composition and bioavailability of nutrients in Moringa oleifera leaf meal from South African ecotype. Nutritional evaluation (proximate, mineral, vitamins and antinutrients, amino acids and fatty acids analyses) was performed using AOAC, ICP-OES and GC+MS techniques respectively. Bioavailability of nutrients involved formulation of diets deficient in minerals and vitamins; and proteins supplemented with Moringa oleifera leaf meal (MOLM) at 0, 3, 5 and 10% respectively. Growth performance, hematological, biochemical and histopathological evaluations were used to assess the effect of MOLM supplementation. Proximate and mineral evaluation revealed that the leaves were rich in protein (28.72%) and carbohydrate (28.84%), calcium content was (1603.33 mg/100g), potassium (1690 mg/100g), zinc (13.03 mg/100g) and iron (21.13 mg/100g). Vitamin E content was the highest (89.43 mg/100g) followed by vitamic C (24.9 mg/100g) and vitamin A (12.98 mg/100g). Fatty acids analysis detected were fifteen of which polyunsaturated fatty acid linoleic acid (56.36) and alpha-linolenic acid (687.58) were highest and behenic acid (22:0) characteristics of Moringa (4.11%) were detected. Seven of the detected fatty acids were saturated fatty acids, though relatively low, with stearic acid having the highest value. On the other hand fifteen of the amino acids, 7 were essential (valine, leucine, isoleucine, methionine, threonine and phenylalanine) were detected; while alanine, proline, serine, aspartic acid, cysteine, glutamic acid, asparagine and tyrosine were non- essential amino acid. Moringa oleifera had low quantities of antinutrients in relation to minerals, thus nutrients will easily ne available. Amino and fatty acids profile of nutrient deficient diets supplemented with MOLM revealed that six essential amino acids were detected in the diets. However, the essential amino acid (EAA) in MOLM with the highest value was threonine (500.47±23.03mg/L), while the lowest was methionine (75.65±5.31mg/L). Leucine was highest in PD10 (234.32±27.98 mg/l) 15 and lowest in PD3. Predominant amino acid in VMD diet was glutamic acid (966.76±208.92 mg/l), while methionine was lowest (197.14±35.90). Caproic acid was the most prominent unsaturated fatty acid in the diets and was highest in the PD diet. Palmitoleic acid was highest in the control diet (8.19±0.56 mg/L) and lowest in PD3 but an increase was observed as the levels of MOLM increased in the diets. Linoleic acid values obtained were significantly higher in PD diet, lower in control diet, compared to other diets. Linolenic acid (C18-3n6) was higher in PD10 (63.48±3.84 mg/L) compared to the control diet (6.05±0.14 mg/L). The highest unsaturated fatty acid in all the feed samples was linoleic acids ranging from 54.48±5.61 to 296.26±7.20 mg/L. the highest omega-3 (n-3) fatty acid content (63.48±3.38 mg/L) was in PD10 and was almost 10 times higher than the value recorded for control. Rats treated on vitamin mineral deficient (VMD) diet showed no significant changes in growth performances and blood parameters except in certain indices. Rats on VMD diet had lowest haemoglobin levels, whereas haemoglobin increased with MOLM levels. No significant differences in haematocrit, MCH, MCHC, platelets, RDW and MPV were observed in all treatments and control. However, VMD rats showed decrease in haemoglobin, increase in WBC and platelets. Electrolytes and glucose for all treatments and control were not significantly different, but, control and VMD10 diets rats showed significantly higher values for creatinine compared to MOLM diets; total protein and albumin increased with MOLM and were higher than in VMD and control rats. Serum activities of liver, cardiac, adrenal marker enzymes were significantly lower in MOLM rats compared to VMD and control. Mild congestion in VMD and VMD3 rat’s liver and diffused congestion in the kidney of VMD diet fed rats was observed. Protein deficient diets supplemented with MOLM had a negative impact on feed intake and growth parameters. Rats fed PD and PD5 consumed significantly less diet than those fed PD10, PD3 diets respectively. White blood cells decreased with increasing levels of MOLM 16 supplementation. Differential white cell count (Neutrophils, lymphocytes, monocytes, eosinophils and basophils) followed the same trend though not statistically significant (P>0.05). Furthermore, histopathological evaluation of organs revealed that no abnormalities were in heart and liver and kidney of rats fed on the control diet, while mild congestion in the liver and myocardium (heart) were observed in rats fed with protein deficient diet. No visible abnormalities were observed in the heart, kidney and liver of animals on the PD 10 diet, but myocardial fibres showing intense eosinophilia was detected in heart muscles of rats fed PD and PD3 diets. In this study, MOLM had a negative impact on feed intake and growth performance of animals and haematology. Blood biochemistry and histology suggest that MOLM has the potential of defending the body against infection with hematinic and blood enhancing qualities. Protein deficiency led to a significant elevation in the serum lipid profile of rats especially cholesterol even with increase in MOLM. PD10 had the highest triglycerides content when compared to the control but was lower (p>0.05) to that of PD. There was an increase in crude fat, ADF, NDF and protein in faecal samples of rats supplemented with MOLM diets while a decrease in moisture and ash was observed compared to the control.Vitamin and mineral deficiency resulted in significant decrease in serum cholesterol, triglycerides and HDL-C when compared to the control. There was a slight increase in excretion for all elements with increasing MOLM. Total removal of minerals and vitamins from the VMD experimental diets seemed not to have any visible negative impact on performance of the rats probably because of residual micronutrients present in other ingredients used in the feed formulation. MOLM could not replace protein in protein deficient diets.
Full Text:
Date Issued: 2019

Bioinformatic analysis, isolation and kinetic characterisation of red algae (Gelidium capense) dehydrogenases

Authors: Gogela, Yanga
Date: 2019
Subjects: Bioinformatics Chondrus crispus
Language: English
Type: Thesis , Masters , MSc
Identifier: http://hdl.handle.net/10353/19164 , vital:39878
Description: Lactate and alcohol dehydrogenases have attracted much attention in various industries and scientific research for their ability to produce chirally pure compounds and be assayed for activity using more straightforward and reproducible assay methods. These enzymes have been previously isolated and purified from various plants, animals and microorganisms. So far, the molecular and biochemical properties of enzymes from these dehydrogenase families in red algae are mostly unknown. Red macroalgae have been used for centuries for the treatment of various diseases and as a source of ingredients in the food industry. The aim of this study was to identify genes in the sequenced red algae genomes that encode dehydrogenases, to use bioinformatic tools to confirm that the proteins encoded are dehydrogenases and to isolate and kinetically purify alcohol or lactate dehydrogenase from red algae species found along the coastline of the Eastern Cape Province. A combination of bioinformatics tools, molecular and biochemical techniques were used to identify, purify, and characterise ADH and LDH enzymes. Bioinformatics analysis revealed two alcohol dehydrogenase genes and two hypothetical genes encoding functional domains similar to D-lactate dehydrogenases from other species. The ADH and LDH-like genes shared low sequence identity at the protein level with medium-chain dehydrogenases/reductases (MDRs) and 2-hydroxy acid dehydrogenases, respectively. These two dehydrogenase genes showed a highly conserved NAD-binding motif (Rossmann-fold) similar to many other NAD-dependent dehydrogenases. The ADH and LDH proteins contained no signal peptides and may be located in the cytoplasm. The phylogenetic tree analysis showed that the two ADH genes belonged to cinnamyl and class III alcohol dehydrogenases, whereas the LDHlike genes were grouped with D-lactate dehydrogenases from other organisms. The ADH and LDH gene family showed cis-acting regulatory elements that are mostly involved in stress response and hormonal response. Structural analysis showed that the dehydrogenases 3D structure predicted models comprise of two domains, namely the substrate binding and the coenzyme binding domains that are rich in beta-strands secondary structure elements. The LDH from red algae was purified approximately 4-fold with a specific activity of 0.044 U/mg. The purified LDH enzyme had a molecular weight of approximately 37kDa. The LDH was active across a broad pH range from 5-9 with a pH optimum observed at 7.5. The LDH ii enzyme in red algae exhibits a temperature optimum of 40 ⁰C and heat stability up to 40 ⁰C. Above 50 °C the LDH activity rapidly decreased showing that the LDH in red algae is not thermostable. The LDH enzyme showed a Km value of 0.8 mM and Vmax of 0.0067 mM.min-1 when using sodium pyruvate as a substrate.
Full Text:
Date Issued: 2019

Characterization and antibiogram fingerprints of Enterobacteriaceae and Listeria monocytogenes in irrigation water and agricultural soil samples collected from Amathole and Chris Hani District Municipalities in the Eastern Cape Province, South Africa

Authors: Iwu, Chidozie Declan
Date: 2019
Subjects: Listeria monocytogenes Enterobacteriaceae
Language: English
Type: Thesis , Masters , MSc
Identifier: http://hdl.handle.net/10353/17187 , vital:40864
Description: Characterization and antibiogram fingerprints of Enterobacteriaceae and Listeria monocytogenes in irrigation water and agricultural soil samples collected from Amathole and Chris Hani District Municipalities in the Eastern Cape Province, South Africa
Full Text:
Date Issued: 2019

Characterization of the heat source of thermal aquifers within the Soutpansberg Basin in the Limpopo Province, South Africa: Evidence from geophysical and geological investigations

Authors: Nyabeze, Peter Kushara
Date: 2019
Subjects: Basins (Geology) -- Analysis Geology, Structural -- South Africa
Language: English
Type: Thesis , Doctoral , PhD (Geology)
Identifier: http://hdl.handle.net/10353/15167 , vital:40192
Description: The research was conducted to contribute towards the knowledge base on the potential for geothermal energy in the Soutpansberg Basin, located in the Limpopo Province of South Africa. The focus area was Siloam, an area that hosts a hottest spring with the highest recorded temperature of 67.5°C. The research involved visits to the Soutpansberg Basin, water sampling, carrying out ground geophysical surveys, and high-level processing of airborne magnetic data to determine depths and temperatures of magnetic sources. The water samples from the hot springs were found to be enriched in sodium, bicarbonate and chlorine with very low concentrations of other element species. The chemical composition of the spring water indicated a source chemistry comprising of the Na-ClHCO3 water assemblage that is a typical signature for deep circulating groundwater of meteoric origin. The circulation depth was inferred to be 2.0 km. The increased resolution of the ground magnetic, electrical resistivity tomography, and electromagnetic conductivity methods data made it possible to delineate subsurface structures at the spring such as dykes, sills, faults and fractures from generated depth models. Modelling of ground magnetic data showed that the Siloam hot spring occurred between two interpreted north dipping dykes approximately 150 m apart. The minimum depth extent of the dykes was interpreted to be 650 m. The magnetic susceptibility values determined from rock measurements and modelling of magnetic data indicated the presence of volcanic and metamorphic rocks. Electromagnetic profiling data showed that there were three main high conductivity zones in the study area with values above 100 mS/m; A central zone associated with the spring; A zone to the south of the spring and a north zone associated with the Siloam Fault. Ground geophysics survey results confirmed the existence of the Siloam Fault. Two artesian boreholes with water warmer than 40 °C were identified to the south of the Siloam hot spring. Both electromagnetic conductivity and electrical resistivity tomography surveys delineated lateral and vertical variation in the bedrock to depths of 40 m to 60 m. Water bearing structures that could be faults, or fractures were identified. Layering due to weathering and water content was found to be in the depth range of 20 m to 40 m. The depths of the potential heat sources were computed from the radially averaged power spectrum of airborne magnetic data for square blocks with side dimensions L of 51 km, 103 km, and 129 km. Spectral analysis based approaches namely Centroid method, Spectral peak method, and the Fractal based approach were used for computing depth and temperatures to heat sources. Airborne magnetic data sets with larger window sizes were preferred for depth computations, as they preserved spectral signatures of deeper sources and reduced the contribution of shallower sources. The size of the data windows did not have a marked effect of depth and temperature values. Shallower magnetic sources depths of approximately 2.0 km were delineated using the Euler deconvolution method. An anticlinal feature at depths of 2.0 to 4.5 km was 4 Final Submission of Thesis, Dissertation or Research Report/Project, Conference or Exam Paper delineated in the central part of the basin. Spectral analysis results indicated that the depth to the top of magnetic sources was at 3.5 km to 6.2 km; the centroid of the basement at 7.92 km to 13.41 km, and the basal below 11.09 km and 14.08 km. The lower end depth spectrum was determined from application of the Centroid method with the deeper being results from the Fractal based approach. The Spectral peak method was useful for determining the depth to the top of magnetic sources. The temperature of the top of magnetic sources and basement centroid were computed to be in the range 234.00 °C to 281.34 °C. Magnetic source depths and basal temperatures that were in the Curie point range within which rocks lose magnetism due to heat were determined, using a computation approach that utilised fractal parameters, to be 21.39 km and 577.42 °C, respectively. Increasing the value of the fractal parameter β from 0 to 4, had an effect of retaining deeper depths and higher temperatures. The fractal parameter β range of 3 to 4 that gave the Curie point parameters indicated basal rock types with an igneous predisposition. The research highlighted evidence for the existence of the Soutpansberg Basin Geothermal Field (SBGF). The area around Siloam is a potential target for drilling exploration geothermal energy boreholes based on the occurrence of hot springs, shallow heat source depths, anticlinal structure, high formation temperatures, deep circulating water and the achieved Curie point temperature.
Full Text:
Date Issued: 2019

Showing items 161 - 180 of 499

Chemical evaluation, in vitro ruminal dry matter (DM) degradability and ruminal biological activity of common browse tree fruits of Alice

Integration of nanostructured metal sulfides into titanium (iv) oxide for high performance dye sensitized solar cell

Investigating communal farmer’s perceptions on production practices and evaluating pre-slaughter responsiveness of extensively reared Boran and Nguni steers

Cultivation, nutritional and pharmacological evaluation of Celosia argentea (L) Kuntze: an endangered wild vegetable in the Eastern Cape Province of South Africa

Studies on vine storage methods, planting techniques, paclobutrazol treatment, planting density and weevil management on sweetpotato (ipomoea batatas l.lam) cultivars promoted in South Africa

Surveillance study on pathogenic Acinetobacter species in freshwater environment of the Amathole and Chris Hani District Municipalities, Eastern Cape, South Africa

Profitability and technical efficiency of small-scale organic crop farmers’ in the Eastern Cape Province of South Africa

A comparative analysis of mobile application development frameworks: A case study of mobile application development for water usage management in Alice and Fort Beaufort communities

A Model for Intrusion Detection in IoT using Machine Learning

Aeolian processes and landforms at Mesrug on sub-Antarctic Marion Island

Amaranth (Amaranthus cruentus) growth and nutritional contents as affected by nitrogen and potassium fertiliser and plant density

An Assessment of the Environmental Impacts of Urban Sprawl in Buffalo City Metropolitan Municipality, Eastern Cape Province

Analyses of Retail and Transport Geography of Liquefied Petroleum Products in Ibadan metropolis, Nigeria

Application of some missing data techniques in estimating missing data in high blood pressure covariates

Assessment of phytochemical constituents, antioxidant properties and cytotoxicity potentials of Leonutis leonurus and Boophone disticha extracts used in the management of Alzheimer’s disease in Hogsback, Eastern Cape, South Africa

Assessment of some bacteria species isolated from woodlands of Raymond Mhlaba Local Municipality for high activity laccase production

Bioavailability of nutrients in a diet enriched with moringa oleifera lam. Leaves using wistar rats

Bioinformatic analysis, isolation and kinetic characterisation of red algae (Gelidium capense) dehydrogenases

Characterization and antibiogram fingerprints of Enterobacteriaceae and Listeria monocytogenes in irrigation water and agricultural soil samples collected from Amathole and Chris Hani District Municipalities in the Eastern Cape Province, South Africa

Characterization of the heat source of thermal aquifers within the Soutpansberg Basin in the Limpopo Province, South Africa: Evidence from geophysical and geological investigations