Synthesis and characterization of group 12 dithiolate complexes as single source precursors for the preparation of hexadecylamine capped metal sulfide nanoparticles and polymer
- Authors: Osuntokun, Jejenija
- Date: 2016
- Subjects: Nanotechnology Nanoparticles Semiconductors
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/14060 , vital:39801
- Description: A series of heteroleptic mixed ligand complexes of some alkyl substituted thiourea, tetramethyl thiuram disulfide and 1-cyano-1-carboethoxy-2,2 ditholate of Zn(II) Cd(II) and Hg(II) have been synthesized by stoichiometry reactions of the ligands with respective metal salts. They have been characterized with analytical and spectroscopic techniques. Seven out of the 19 complexes synthesized are pyridine 2, 2 bipyridine and 1, 10 phenanthroline adducts of dissopropyl parent adducts of Zn(II) and Cd(II) complexes. All the complexes are proposed as four coordinate except the pyridine adducts, 2, 2’ bipyridine and 1, 10 phenanhroline adducts that are proposed as five and six coordinate respectively. All the complexes are solid, air stable and moisture stable for a many months. They are not soluble in common organic solvents but partially soluble in coordinating solvents like DMF and DMSO and due to their insolubility problems all attempts to grow single crystal of the complexes proved abortive. The complexes gave respective metal sulfide on thermal decomposition in TGA and this makes them to be potentially useful single source precursor for the synthesis of metal sulfide. All the complexes were invariably thermolysed in HDA to synthesis a series of HDA-capped ZnS, CdS and HgS nanoparticles. The optical properties of the nanoparticles reveal that they are all blue-shifted from the absorbance edge and this confirms quantum confinement of the nanoparticles. The transmittance electron microscope showed that the nanoparticles are in nanodimension. ZnS nanoparticles from the pyridine adducts gave HDA-capped ZnS nanoparticles with a mixture of hexagonal and cubic phases while the HDA capped CdS from the 2, 2 bipyridine and 1,10 phenanthroline gave anisotropic nanoparticles. The sizes of the CdS from the 1,10 phenanthroline adducts were also found to be biggest while CdS nanoparticles from 2,2 bipyridine adduct were also revealed to be bigger than the particle sizes obtained from the parent complex, (1-cyano-1 carboethoxyethylene-2,2-dithiolato- κ,S’S)-bis(N, N’-diisopropylthiourea -κS)cadmium(II). ZnS and CdS polymer encapsulated nanocomposites were also synthesized using a solution casting method. The polymers employed were; Polymethyl metharcrylate (PMMA), Poly(vinly alcohol) (PVA), and poly vinyl pyrrolidone (PVP). The structural and thermal properties of the pure polymers and the respective nanocomposites were investigated. It was observed that the ZnS/PVA and CdS/PVA were the most thermally stable composites when the thermal stability of the pure polymers were compared relative to the nanocomposites using data obtained from thermal decomposition results of the TGA.
- Full Text:
- Date Issued: 2016
- Authors: Osuntokun, Jejenija
- Date: 2016
- Subjects: Nanotechnology Nanoparticles Semiconductors
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/14060 , vital:39801
- Description: A series of heteroleptic mixed ligand complexes of some alkyl substituted thiourea, tetramethyl thiuram disulfide and 1-cyano-1-carboethoxy-2,2 ditholate of Zn(II) Cd(II) and Hg(II) have been synthesized by stoichiometry reactions of the ligands with respective metal salts. They have been characterized with analytical and spectroscopic techniques. Seven out of the 19 complexes synthesized are pyridine 2, 2 bipyridine and 1, 10 phenanthroline adducts of dissopropyl parent adducts of Zn(II) and Cd(II) complexes. All the complexes are proposed as four coordinate except the pyridine adducts, 2, 2’ bipyridine and 1, 10 phenanhroline adducts that are proposed as five and six coordinate respectively. All the complexes are solid, air stable and moisture stable for a many months. They are not soluble in common organic solvents but partially soluble in coordinating solvents like DMF and DMSO and due to their insolubility problems all attempts to grow single crystal of the complexes proved abortive. The complexes gave respective metal sulfide on thermal decomposition in TGA and this makes them to be potentially useful single source precursor for the synthesis of metal sulfide. All the complexes were invariably thermolysed in HDA to synthesis a series of HDA-capped ZnS, CdS and HgS nanoparticles. The optical properties of the nanoparticles reveal that they are all blue-shifted from the absorbance edge and this confirms quantum confinement of the nanoparticles. The transmittance electron microscope showed that the nanoparticles are in nanodimension. ZnS nanoparticles from the pyridine adducts gave HDA-capped ZnS nanoparticles with a mixture of hexagonal and cubic phases while the HDA capped CdS from the 2, 2 bipyridine and 1,10 phenanthroline gave anisotropic nanoparticles. The sizes of the CdS from the 1,10 phenanthroline adducts were also found to be biggest while CdS nanoparticles from 2,2 bipyridine adduct were also revealed to be bigger than the particle sizes obtained from the parent complex, (1-cyano-1 carboethoxyethylene-2,2-dithiolato- κ,S’S)-bis(N, N’-diisopropylthiourea -κS)cadmium(II). ZnS and CdS polymer encapsulated nanocomposites were also synthesized using a solution casting method. The polymers employed were; Polymethyl metharcrylate (PMMA), Poly(vinly alcohol) (PVA), and poly vinyl pyrrolidone (PVP). The structural and thermal properties of the pure polymers and the respective nanocomposites were investigated. It was observed that the ZnS/PVA and CdS/PVA were the most thermally stable composites when the thermal stability of the pure polymers were compared relative to the nanocomposites using data obtained from thermal decomposition results of the TGA.
- Full Text:
- Date Issued: 2016
Two uses of DNA sequence variation in tracing evolutionary processes in Old World primates (Primates: Catarrhini)
- Authors: Dosi, Banele
- Date: 2016
- Subjects: Primates -- Evolution Monkeys Cercopithecidae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/8022 , vital:31464
- Description: Primate evolution is particularly interesting to humans, because it includes our own history. Molecular genetics is by far the most dynamic field in contemporary biology, and offers a host of new techniques for investigating evolutionary processes and patterns. In the mid-twentieth century molecular genetics evolved from being a means of visualising hidden variation (e.g. allozymes) to tracing phylogenetic relationships between and among species (evolutionary histories of populations), and now has a wide variety of applications in medicine, species identification and relationships, and even wildlife forensics. For my Master’s project I investigated two applications of molecular genetic analysis to questions regarding the evolution of Old World monkeys (Catarrhini). First, I participated in a study designed to test the hypothesis that different primate social structures – particularly mating systems – may be reflected in the structure of a species genome. We investigated whether increased sperm production as a result of sexual selection increases the number of copy number variations (CNVs) that can be detected by comparing the male specific region Y (MSY) located on the Y chromosome in a sample of primate species. We did not find a clear differentiation between the primate species as hypothesised, which thus requires a more complex explanation, e.g. in terms of the type of environment rather than the mating system of the species, or possibly the active/inactive status of the genes. The second part of my study was phylogeographic in approach. I collaborated with researchers studying the distribution of Afromontane samango monkeys (Cercopithecus albogularis labiatus) in the Eastern Cape. I sequenced tissues from 5 samango monkey specimens found opportunistically in the Hogsback and coastal forests and analysed their genetic variation relative to the data published by Dalton et al. 2015. The Hogsback sample was not monophyletic relative to the sample from the coastal forests, indicating that, on the basis of this very small sample size, these populations have not been separated historically. In order to validate this conclusion, I will need to investigate a larger sample size. From this study I developed valuable skills in the areas of the laboratory techniques involved in molecular sequence analysis, and an appreciation for the importance of large sample sizes in deriving reliable results. I intend to continue in the future with a phylogeographic study of samango monkeys.
- Full Text:
- Date Issued: 2016
- Authors: Dosi, Banele
- Date: 2016
- Subjects: Primates -- Evolution Monkeys Cercopithecidae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/8022 , vital:31464
- Description: Primate evolution is particularly interesting to humans, because it includes our own history. Molecular genetics is by far the most dynamic field in contemporary biology, and offers a host of new techniques for investigating evolutionary processes and patterns. In the mid-twentieth century molecular genetics evolved from being a means of visualising hidden variation (e.g. allozymes) to tracing phylogenetic relationships between and among species (evolutionary histories of populations), and now has a wide variety of applications in medicine, species identification and relationships, and even wildlife forensics. For my Master’s project I investigated two applications of molecular genetic analysis to questions regarding the evolution of Old World monkeys (Catarrhini). First, I participated in a study designed to test the hypothesis that different primate social structures – particularly mating systems – may be reflected in the structure of a species genome. We investigated whether increased sperm production as a result of sexual selection increases the number of copy number variations (CNVs) that can be detected by comparing the male specific region Y (MSY) located on the Y chromosome in a sample of primate species. We did not find a clear differentiation between the primate species as hypothesised, which thus requires a more complex explanation, e.g. in terms of the type of environment rather than the mating system of the species, or possibly the active/inactive status of the genes. The second part of my study was phylogeographic in approach. I collaborated with researchers studying the distribution of Afromontane samango monkeys (Cercopithecus albogularis labiatus) in the Eastern Cape. I sequenced tissues from 5 samango monkey specimens found opportunistically in the Hogsback and coastal forests and analysed their genetic variation relative to the data published by Dalton et al. 2015. The Hogsback sample was not monophyletic relative to the sample from the coastal forests, indicating that, on the basis of this very small sample size, these populations have not been separated historically. In order to validate this conclusion, I will need to investigate a larger sample size. From this study I developed valuable skills in the areas of the laboratory techniques involved in molecular sequence analysis, and an appreciation for the importance of large sample sizes in deriving reliable results. I intend to continue in the future with a phylogeographic study of samango monkeys.
- Full Text:
- Date Issued: 2016
Applicability of putative probiotic bacteria to replace antibiotics as growth promoters in commercial and indigenous piglets
- Authors: Dlamini, Ziyanda Confidence
- Date: 2017
- Subjects: Antibiotics Dietary supplements Piglets
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11428 , vital:39071
- Description: Antibiotic use in pig production contributes to development of antimicrobial resistance in food animals and risk of antibiotic residues in animal food products. The use of probiotics appears to be the potential alternative to antibiotics. This work is designed to validate the applicability of administered direct-fed putative probiotic strains of Lactobacillus reuteri ZJ625, Lactobacillus reuteri VB4, Lactobacillus salivarius ZJ614 and Streptococcus salivarius NBCR 13956 on growth performance, hematological parameters, and antibody stimulation in weaned commercial and indigenous pigs. Forty-five weaned piglets were divided into five treatment experimental groups as follows: Diet with: antibiotic (PC), No antibiotic and no probiotic (NC), Probiotic (P1) (P2) combination of probiotics (P3). Piglets’ performance were monitored during the trial. Faecal and ileum samples were collected for microbial count analysis. Blood samples were collected from the sacrificed piglets at the end of the trial, for the hematological and biochemical analysis and probiotics ability to stimulate immunoglobulin G (IgG). Four probiotic strains were tested for cell surface hydrophobicity against xylene, chloroform and ethyl acetate. The strains were also tested for auto-aggregation and co-aggregation abilities. Enterococcus faecalis ATCC 29212 was used as a control pathogen in the co-aggregation ability test. The probiotic strains were also screened for presence of virulence and resistance genes. DNA was extracted from all the four probiotic strains using ZR Fungal/Bacterial DNA MiniPepTM (Zymo Research, USA) following manufacturer’s instructions. The DNA samples were later amplified in PCR reactions with specific primers to detect virulence genes of adhesion collagen protein (ace), aggregation substances (agg and asa); antibiotic resistance genes of: Vancomycin vanA, Vancomycin vanC1 and Vancomycin vanC2/3. The data was analyzed by one-way ANOVA using SAS statistics software (SAS 9.3) (2003). Results from the study revealed that supplementation of probiotics had no effect on feed intake (FI) in all of the experimental groups. However, supplementation of probiotics in P3 treatment resulted in greater average daily gain (ADG) and improved feed conversion ratio (FCR) of weaned piglets (p < 0.05). Microbial count of fecal samples from all the treatment groups did not differ while ileum samples had lower enteric bacteria in P3 group as compared to other treatments. Concentration of albumin, globulin, neutrophils and basophils were high in NC treatment compared to other treatments. (p < 0.05). IgG concentration was highest in P3 compared to other treatment (p < 0.05). All probiotics strains showed high hydrophobicity to all solvents used in the test. Cell Surface Hydrophobic was highest in xylene (78percent – 84percent), followed by chloroform (68percent – 75percent) and lowest in ethyl acetate (52percent - 60percent). All of the test strains showed high auto-aggregation ability after 4 hr of incubation. L .reuteri VB4 exhibited highest auto-aggregation ability of 70percent, while the least auto-aggregation ability of 60percent was observed for L. salivarius ZJ614. In the co-aggregation assays, all probiotic bacterial strains exhibited a strong co-aggregation of 45percent to 56percent after 4 hr of incubation at 37 °C. L. reuteri VB4 exhibited highest co-aggregation ability while L. salivarius ZJ614 exhibited the lowest co-aggregation ability. No presence of virulence genes ace and asa was detected in all of the putative probiotic strains, but agg virulence gene was detected in L. reuteri VB4 strains. L. reuteri VB4 and S. salivarius NBRC13956 had resistance genes vanC 2/3 and vanC1, respectively. Overall, the results from this study, suggest that the candidate probiotics strains have enhanced the growth and measured blood parameters of the weaned piglets used in these experiments, and also, the probiotic strains have the abilities to initiate the stimulation of IgG. Probiotics could be used as a novel alternative to antibiotics in the animal nutrition and production, with the abilities to confer health benefits and promote growth. The outcome of the research advocates that these probiotics will be beneficial to pig production, and might outcompete the current antibiotics in use as growth promoters. One of the major advantages of probiotics to pig industry is the production of antibiotic free and good quality pork meat to local and international consumers, thus, enhancing South African Pork industry.
- Full Text:
- Date Issued: 2017
- Authors: Dlamini, Ziyanda Confidence
- Date: 2017
- Subjects: Antibiotics Dietary supplements Piglets
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11428 , vital:39071
- Description: Antibiotic use in pig production contributes to development of antimicrobial resistance in food animals and risk of antibiotic residues in animal food products. The use of probiotics appears to be the potential alternative to antibiotics. This work is designed to validate the applicability of administered direct-fed putative probiotic strains of Lactobacillus reuteri ZJ625, Lactobacillus reuteri VB4, Lactobacillus salivarius ZJ614 and Streptococcus salivarius NBCR 13956 on growth performance, hematological parameters, and antibody stimulation in weaned commercial and indigenous pigs. Forty-five weaned piglets were divided into five treatment experimental groups as follows: Diet with: antibiotic (PC), No antibiotic and no probiotic (NC), Probiotic (P1) (P2) combination of probiotics (P3). Piglets’ performance were monitored during the trial. Faecal and ileum samples were collected for microbial count analysis. Blood samples were collected from the sacrificed piglets at the end of the trial, for the hematological and biochemical analysis and probiotics ability to stimulate immunoglobulin G (IgG). Four probiotic strains were tested for cell surface hydrophobicity against xylene, chloroform and ethyl acetate. The strains were also tested for auto-aggregation and co-aggregation abilities. Enterococcus faecalis ATCC 29212 was used as a control pathogen in the co-aggregation ability test. The probiotic strains were also screened for presence of virulence and resistance genes. DNA was extracted from all the four probiotic strains using ZR Fungal/Bacterial DNA MiniPepTM (Zymo Research, USA) following manufacturer’s instructions. The DNA samples were later amplified in PCR reactions with specific primers to detect virulence genes of adhesion collagen protein (ace), aggregation substances (agg and asa); antibiotic resistance genes of: Vancomycin vanA, Vancomycin vanC1 and Vancomycin vanC2/3. The data was analyzed by one-way ANOVA using SAS statistics software (SAS 9.3) (2003). Results from the study revealed that supplementation of probiotics had no effect on feed intake (FI) in all of the experimental groups. However, supplementation of probiotics in P3 treatment resulted in greater average daily gain (ADG) and improved feed conversion ratio (FCR) of weaned piglets (p < 0.05). Microbial count of fecal samples from all the treatment groups did not differ while ileum samples had lower enteric bacteria in P3 group as compared to other treatments. Concentration of albumin, globulin, neutrophils and basophils were high in NC treatment compared to other treatments. (p < 0.05). IgG concentration was highest in P3 compared to other treatment (p < 0.05). All probiotics strains showed high hydrophobicity to all solvents used in the test. Cell Surface Hydrophobic was highest in xylene (78percent – 84percent), followed by chloroform (68percent – 75percent) and lowest in ethyl acetate (52percent - 60percent). All of the test strains showed high auto-aggregation ability after 4 hr of incubation. L .reuteri VB4 exhibited highest auto-aggregation ability of 70percent, while the least auto-aggregation ability of 60percent was observed for L. salivarius ZJ614. In the co-aggregation assays, all probiotic bacterial strains exhibited a strong co-aggregation of 45percent to 56percent after 4 hr of incubation at 37 °C. L. reuteri VB4 exhibited highest co-aggregation ability while L. salivarius ZJ614 exhibited the lowest co-aggregation ability. No presence of virulence genes ace and asa was detected in all of the putative probiotic strains, but agg virulence gene was detected in L. reuteri VB4 strains. L. reuteri VB4 and S. salivarius NBRC13956 had resistance genes vanC 2/3 and vanC1, respectively. Overall, the results from this study, suggest that the candidate probiotics strains have enhanced the growth and measured blood parameters of the weaned piglets used in these experiments, and also, the probiotic strains have the abilities to initiate the stimulation of IgG. Probiotics could be used as a novel alternative to antibiotics in the animal nutrition and production, with the abilities to confer health benefits and promote growth. The outcome of the research advocates that these probiotics will be beneficial to pig production, and might outcompete the current antibiotics in use as growth promoters. One of the major advantages of probiotics to pig industry is the production of antibiotic free and good quality pork meat to local and international consumers, thus, enhancing South African Pork industry.
- Full Text:
- Date Issued: 2017
Comparative analysis of zero-tillage and conventional tillage practices in the Amahlathi local municipality of the Eastern Cape province of South Africa
- Authors: Gomo, Zintle
- Date: 2017
- Subjects: Tillage--South Africa--Eastern Cape Farms, Small--South Africa--Eastern Cape No-tillage--South Africa--Eastern Cape
- Language: English
- Type: Thesis , Masters , Agricultural Economics
- Identifier: http://hdl.handle.net/10353/11586 , vital:39087
- Description: The current interest in zero tillage/no-till technologies is a result of the need to reduce excessive land degradation in most crop producing areas as well as to enhance sustainable food production. Farmers are always looking for ways to increase yields and profits and zero-tillage may be a way to achieve this goal. However, a systematic comparative study of the performance of zero-tillage and conventional tillage within the former homeland areas of the Eastern Cape Province is lacking. The broad objective of the study is to comparatively analyze zero tillage and conventional tillage and to determine which practice is more beneficial for the land and farmers in the area. Specifically, the study investigated the relative performance of Zero-tillage and conventional–tillage in terms of quantity produced per farm and per hectare, factors influencing the adoption rate of zero tillage and conventional tillage and to determine the relative impact of zero-tillage and conventional tillage on household income. The study was carried out in Amahlathi Local Municipality in the Eastern Cape Province and employed survey data obtained from 100 respondents using conventional tillage and zero tillage farmers growing spinach, cabbage, beetroot, maize, and potatoes. The study employed a cross-sectional research design. A multistage stratified sampling procedure was used in which the first stage involved selecting respondents from Amahlathi Local Municipally. This was followed by the selection of villages and then the respondents. This was done through stratification of smallholder farmers from the different Villages. This was followed by random sampling which was used to get the sample size for the study. Stata and SPSS were used to analyze the data. Descriptive statistics was used to examine current farming practices in the Eastern Cape Province while Propensity Score Matching was employed to estimate the factors that had an impact on zero tillage adoption as well as the relative impact of zero tillage and conventional tillage on household income. Gross margin analysis was used to estimate profitability of zero tillage and conventional. female farmers are participating more in zero tillage with 63.8percent while males are dominating the conventional tillage with 51.6percent. These results show that females play a crucial role in decision making when it comes to agriculture and adoption of new agricultural technologies. The majority of the farmers involved in the study were young farmers with 58percent from zero tillage and 42percent practically involved in conventional tillage. Moreover, the study showed that 41percent of the respondents practising ZT were married, and about 39percent of the respondents practising conventional tillage were married. The marital status of the respondents suggested that zero-tillage farmers were relatively stable in their farming activities as compared to conventional tillage. The results presented that 52.2percent of the respondents who practised zero tillage were better educated than the 48.4percent of the respondents practising conventional tillage. The respondents that were specialising in zero-tillage, about 41% relied on farming, 6% relied on salaried income and 54percent relied on social grants. On the other hand, respondents that were specialising in conventional tillage about, 26percent relied on farming, 16percent relied on salaried income, while 58percent relied on social grants. The respondents that were specialising in zero-tillage, about 28percent used communal land, 1percent used own land and 71percent used family land. On the other hand, respondents that were specialising in conventional tillage about, 42percent used communal land, 7percent use own land and 52percent used family land. The average household size for both groups of farmers is 5 people per household. Household income distribution for conventional tillage is giving the farmers an average of R3187.10 income while the zero tillage is giving them an income of R2305.80 on average. The study revealed that the landholdings for conventional tillage agriculture tend to be more (1.77 ha) compared to zero tillage (0.79 ha) agriculture. The Propensity Score Matching results indicated that participation in smallholder zero tillage farming contributes to household income. This implies that participating in zero tillage farming can contribute to rural livelihoods, increased income and production yields. The study results showed that households chose different farming systems based on their knowledge, level of education and farming experiences. The gross margin results show that conventional tillage farming households generated more income than zero tillage farming households. Farmers who were involved in conventional tillage farming were complaining that yields and income have decreased with time and they are continuing to decrease while farmers who carried out zero tillage farming indicated that their yields and income have improved considerably and continue to increase with time. Thus, support for adopting and implementing zero tillage practices can be an important factor for improving incomes for rural households. Based on the findings highlighted above, the study recommends provision of farm inputs and continuation of government support with more emphasis on strengthening access to inputs and technical assistance. There is a need for support programmes that would help to motivate farmers for better performance. The programmes include infrastructure developments, research and extension activities.
- Full Text:
- Date Issued: 2017
- Authors: Gomo, Zintle
- Date: 2017
- Subjects: Tillage--South Africa--Eastern Cape Farms, Small--South Africa--Eastern Cape No-tillage--South Africa--Eastern Cape
- Language: English
- Type: Thesis , Masters , Agricultural Economics
- Identifier: http://hdl.handle.net/10353/11586 , vital:39087
- Description: The current interest in zero tillage/no-till technologies is a result of the need to reduce excessive land degradation in most crop producing areas as well as to enhance sustainable food production. Farmers are always looking for ways to increase yields and profits and zero-tillage may be a way to achieve this goal. However, a systematic comparative study of the performance of zero-tillage and conventional tillage within the former homeland areas of the Eastern Cape Province is lacking. The broad objective of the study is to comparatively analyze zero tillage and conventional tillage and to determine which practice is more beneficial for the land and farmers in the area. Specifically, the study investigated the relative performance of Zero-tillage and conventional–tillage in terms of quantity produced per farm and per hectare, factors influencing the adoption rate of zero tillage and conventional tillage and to determine the relative impact of zero-tillage and conventional tillage on household income. The study was carried out in Amahlathi Local Municipality in the Eastern Cape Province and employed survey data obtained from 100 respondents using conventional tillage and zero tillage farmers growing spinach, cabbage, beetroot, maize, and potatoes. The study employed a cross-sectional research design. A multistage stratified sampling procedure was used in which the first stage involved selecting respondents from Amahlathi Local Municipally. This was followed by the selection of villages and then the respondents. This was done through stratification of smallholder farmers from the different Villages. This was followed by random sampling which was used to get the sample size for the study. Stata and SPSS were used to analyze the data. Descriptive statistics was used to examine current farming practices in the Eastern Cape Province while Propensity Score Matching was employed to estimate the factors that had an impact on zero tillage adoption as well as the relative impact of zero tillage and conventional tillage on household income. Gross margin analysis was used to estimate profitability of zero tillage and conventional. female farmers are participating more in zero tillage with 63.8percent while males are dominating the conventional tillage with 51.6percent. These results show that females play a crucial role in decision making when it comes to agriculture and adoption of new agricultural technologies. The majority of the farmers involved in the study were young farmers with 58percent from zero tillage and 42percent practically involved in conventional tillage. Moreover, the study showed that 41percent of the respondents practising ZT were married, and about 39percent of the respondents practising conventional tillage were married. The marital status of the respondents suggested that zero-tillage farmers were relatively stable in their farming activities as compared to conventional tillage. The results presented that 52.2percent of the respondents who practised zero tillage were better educated than the 48.4percent of the respondents practising conventional tillage. The respondents that were specialising in zero-tillage, about 41% relied on farming, 6% relied on salaried income and 54percent relied on social grants. On the other hand, respondents that were specialising in conventional tillage about, 26percent relied on farming, 16percent relied on salaried income, while 58percent relied on social grants. The respondents that were specialising in zero-tillage, about 28percent used communal land, 1percent used own land and 71percent used family land. On the other hand, respondents that were specialising in conventional tillage about, 42percent used communal land, 7percent use own land and 52percent used family land. The average household size for both groups of farmers is 5 people per household. Household income distribution for conventional tillage is giving the farmers an average of R3187.10 income while the zero tillage is giving them an income of R2305.80 on average. The study revealed that the landholdings for conventional tillage agriculture tend to be more (1.77 ha) compared to zero tillage (0.79 ha) agriculture. The Propensity Score Matching results indicated that participation in smallholder zero tillage farming contributes to household income. This implies that participating in zero tillage farming can contribute to rural livelihoods, increased income and production yields. The study results showed that households chose different farming systems based on their knowledge, level of education and farming experiences. The gross margin results show that conventional tillage farming households generated more income than zero tillage farming households. Farmers who were involved in conventional tillage farming were complaining that yields and income have decreased with time and they are continuing to decrease while farmers who carried out zero tillage farming indicated that their yields and income have improved considerably and continue to increase with time. Thus, support for adopting and implementing zero tillage practices can be an important factor for improving incomes for rural households. Based on the findings highlighted above, the study recommends provision of farm inputs and continuation of government support with more emphasis on strengthening access to inputs and technical assistance. There is a need for support programmes that would help to motivate farmers for better performance. The programmes include infrastructure developments, research and extension activities.
- Full Text:
- Date Issued: 2017
Production performance, socioeconomic benefits, and agricultural extension services support of scavenging chicken farmers in Raymond Mhlaba Local Municipality, Eastern Cape Province
- Fentele, Ziphozethu https://orcid.org/ 0000-0001-7939-2964
- Authors: Fentele, Ziphozethu https://orcid.org/ 0000-0001-7939-2964
- Date: 2021-03
- Subjects: Broilers (Chickens) , Poultry -- Breeding
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/21490 , vital:48751
- Description: Scavenging chicken production plays a significant role in the lives of rural farmers as it ensures food security by providing eggs and meat to rural farmers almost in all developing nations. Rural farmers not only consume scavenging chickens, they also sell live chickens to customers to generate immediate income and are able to acquire other products using the money from the sales. The purpose of this study was to investigate production performance, socioeconomic benefits, and agricultural extension services support for scavenging chicken producers. The study was carried out in eight villages in Raymond Mhlaba Local Municipality in the Eastern Cape Province of South Africa. This study employed the multistage sampling technique for data collection from respondents between October and November 2018. The study used descriptive statistics, frequencies, percentages and multiple linear regression models to analyse quantitative data that was collected from a survey of 161 rural farmers that rear scavenging chickens. The results reveal that the majority (68.3percent) of the respondents in Raymond Mhlaba Local Municipality were women, while 52percent were married. Forty-eight percent of the respondents had attained high school education. The majority (53.4percent) relied on social grants and a further majority (68.3percent) had 1 to 10 years of experience in scavenging chicken production. The majority (84.5percent) of the households had between 1 and 50 chickens, with an overwhelming majority (95percent) practising free range system. Most (74.5percent) of the chicken houses were built with scrap material found within the community. The supplementary feed that was mostly offered to scavenging chickens was maize. The majority (95.7percent) of respondents experienced disease outbreaks, the most dominant of which was the Newcastle disease. Most (94.4percent) of the farmers offered a variety of indigenous medicines, mainly Aloe Ferrox. In addition, the majority (88.8percent) of the respondents experienced predation challenges The primary purpose of rearing scavenging chickens was consumption. Chickens were slaughtered for home consumption while forty-two percent at most. Most (50.9percent) of the respondents indicated that they offered chickens as gifts and as friendly gestures. The majority (82.0percent) indicated that they did not use chicken for any cultural rituals. A large (88.2percent) number of the respondents felt food secured as a result of rearing scavenging chickens, as they access products such as eggs and meat. The majority (98.8percent) of the respondents had never received any form of training from agricultural extension services. The results of the multiple linear regression model revealed that independent variables such as number of chickens, type of cockerels, number of hens, type of housing, type of training and cost of trainings had strong statistical significant values (p<0.001) zero-order correlation with production performance,while age and gender had statistical significant values at (p<0.05) and (p<0.010). For the improvement of the production performance of scavenging chicken production of rural farmers, the study recommends massive campaign among the farmers by agricultural extension services to create awareness on the dangers inherent in the use of unorthodox approaches to treating pests and diseases in scavenging chicken. Scavenging chicken farmers could be supported with simple technologies that are affordable on housing, medication and feed supplements. Training should focus on housing, disease management and feeding of scavenging chickens. , Thesis (MSc) -- Faculty of Science and Agriculture, 2021
- Full Text:
- Date Issued: 2021-03
- Authors: Fentele, Ziphozethu https://orcid.org/ 0000-0001-7939-2964
- Date: 2021-03
- Subjects: Broilers (Chickens) , Poultry -- Breeding
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/21490 , vital:48751
- Description: Scavenging chicken production plays a significant role in the lives of rural farmers as it ensures food security by providing eggs and meat to rural farmers almost in all developing nations. Rural farmers not only consume scavenging chickens, they also sell live chickens to customers to generate immediate income and are able to acquire other products using the money from the sales. The purpose of this study was to investigate production performance, socioeconomic benefits, and agricultural extension services support for scavenging chicken producers. The study was carried out in eight villages in Raymond Mhlaba Local Municipality in the Eastern Cape Province of South Africa. This study employed the multistage sampling technique for data collection from respondents between October and November 2018. The study used descriptive statistics, frequencies, percentages and multiple linear regression models to analyse quantitative data that was collected from a survey of 161 rural farmers that rear scavenging chickens. The results reveal that the majority (68.3percent) of the respondents in Raymond Mhlaba Local Municipality were women, while 52percent were married. Forty-eight percent of the respondents had attained high school education. The majority (53.4percent) relied on social grants and a further majority (68.3percent) had 1 to 10 years of experience in scavenging chicken production. The majority (84.5percent) of the households had between 1 and 50 chickens, with an overwhelming majority (95percent) practising free range system. Most (74.5percent) of the chicken houses were built with scrap material found within the community. The supplementary feed that was mostly offered to scavenging chickens was maize. The majority (95.7percent) of respondents experienced disease outbreaks, the most dominant of which was the Newcastle disease. Most (94.4percent) of the farmers offered a variety of indigenous medicines, mainly Aloe Ferrox. In addition, the majority (88.8percent) of the respondents experienced predation challenges The primary purpose of rearing scavenging chickens was consumption. Chickens were slaughtered for home consumption while forty-two percent at most. Most (50.9percent) of the respondents indicated that they offered chickens as gifts and as friendly gestures. The majority (82.0percent) indicated that they did not use chicken for any cultural rituals. A large (88.2percent) number of the respondents felt food secured as a result of rearing scavenging chickens, as they access products such as eggs and meat. The majority (98.8percent) of the respondents had never received any form of training from agricultural extension services. The results of the multiple linear regression model revealed that independent variables such as number of chickens, type of cockerels, number of hens, type of housing, type of training and cost of trainings had strong statistical significant values (p<0.001) zero-order correlation with production performance,while age and gender had statistical significant values at (p<0.05) and (p<0.010). For the improvement of the production performance of scavenging chicken production of rural farmers, the study recommends massive campaign among the farmers by agricultural extension services to create awareness on the dangers inherent in the use of unorthodox approaches to treating pests and diseases in scavenging chicken. Scavenging chicken farmers could be supported with simple technologies that are affordable on housing, medication and feed supplements. Training should focus on housing, disease management and feeding of scavenging chickens. , Thesis (MSc) -- Faculty of Science and Agriculture, 2021
- Full Text:
- Date Issued: 2021-03
The impact of rangeland degradation on vegetation cover and soil quality in semi-arid communal rangelands of the Eastern Cape province, South Africa
- Authors: Maziko, Yonela
- Date: 2017
- Subjects: Communal rangelands -- South Africa -- Eastern Cape Land degradation -- South Africa -- Eastern Cape Vegetation management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15056 , vital:40159
- Description: This study was conducted to investigate the influence of degradation on vegetation and soil quality in two semi-arid rangelands in the Eastern Cape Province of South Africa. The study was undertaken in Kwezana and Esigingqini communal areas that showed signs id degradation. The assessment incorporated the soil and grass layer in different degradation levels, namely nondegraded, slightly degraded, moderately and severely degraded. The non-degraded has a sufficient amount of vegetation cover and species composition. The slightly degraded site consists of a few visible bare patches. The moderately degraded areas showed signs of active sheet erosion such as pedestals and a higher percentage of bare areas and the severely degraded area is characterized by dongas and gullies, with vast areas that have no ground cover or top fertile soil layer. Using a step point method, herbaceous species composition was determined within three transects from three plots 100 m x 40 m in each degradation level. The aboveground phytomass production was determined by harvesting herbaceous species within four randomly placed 0.25 m2 quadrats in each transect. Bare ground was determined by counting and recording the distance between tufts within each quadrat. Litter cover was determined by visual observation and rated on a scale of 1 to 5. A number of physical and chemical soil properties were used to quantify the effects of degradation on soil quality. To determine soil chemical properties, three soil samples were collected at a depth of 20 cm, in each plot and analyzed for pH, soil macro (N, C, K, P, Ca, Mg) and micro (Zn, Fe, Mn and Cu) nutrients. Soil compaction was determined using a soil pocket penetrometer. Readings were taken at 5 mm from 30 points placed at 1 m intervals and distributed in a randomly established straight line in each plot. Soil loss was determined using a rainfall simulator. Splash cups were filled with soil and placed under the rainfall simulator for 8 minutes per rainstorm at 360 mm-1 intensity. Results showed that at Esigingqini a total of 20 herbaceous species were identified, 17 of which were grasses. About 60percent of the identified grasses were Increaser II species, 15percent were Increaser II and 25percent Decreasers. In terms of palatability, 50percent of the grass species had poor palatability and the remaining had either average or high palatability. At Kwezana, 18 herbaceous species were identified of which 28percent were Decreasers and 61percent were Increaser II species. Half of the species had low palatability and only 28percent had high palatability. In both communal areas, litter cover was highest (P < 0.05) in the non-degraded areas followed by the slightly degraded sites and this was to be expected. Similarly, in both communal areas, there was a shift in species composition of decreasers and perennial grasses being replaced by annual species of poor quality and low palatability as the degradation levels increased. Results on soil chemical properties showed that the non-degraded areas had higher (P < 0.05) pH levels (8.5) than the severely degraded soils (5). A similar trend following a degradation gradient was observed for some soil nutrients such as N, P or Mg. Both the macro and micro nutrient concentrations were relatively higher (P < 0.05) in summer than in winter in both communal areas. Results on physical properties showed that soil loss and compaction were relatively lower (P <0.05) in the slightly degraded and non-degraded sites and increased with severity of degradation. In both communal areas, the severely degraded areas lost soil up to 1.1 t ha-1 due to degradation and the non-degraded areas had a soil loss of less than 0.8 t ha-1. The rate of soil loss between the severely and non-degraded areas is significantly different. The differences may be attributed to the differences in the vegetation cover which influences the rate of erosion on the various degradation gradients. These results suggest that both the grass layer and soil quality is negatively affected by degradation. Therefore, there is a need for land use practices that promote the sustainable use of rangeland resources. Such practices may include rotational grazing, reseeding, veld resting and fire. Measures to control the consequences of degradation and rehabilitate these deteriorated rangelands must be a priority.
- Full Text:
- Date Issued: 2017
- Authors: Maziko, Yonela
- Date: 2017
- Subjects: Communal rangelands -- South Africa -- Eastern Cape Land degradation -- South Africa -- Eastern Cape Vegetation management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15056 , vital:40159
- Description: This study was conducted to investigate the influence of degradation on vegetation and soil quality in two semi-arid rangelands in the Eastern Cape Province of South Africa. The study was undertaken in Kwezana and Esigingqini communal areas that showed signs id degradation. The assessment incorporated the soil and grass layer in different degradation levels, namely nondegraded, slightly degraded, moderately and severely degraded. The non-degraded has a sufficient amount of vegetation cover and species composition. The slightly degraded site consists of a few visible bare patches. The moderately degraded areas showed signs of active sheet erosion such as pedestals and a higher percentage of bare areas and the severely degraded area is characterized by dongas and gullies, with vast areas that have no ground cover or top fertile soil layer. Using a step point method, herbaceous species composition was determined within three transects from three plots 100 m x 40 m in each degradation level. The aboveground phytomass production was determined by harvesting herbaceous species within four randomly placed 0.25 m2 quadrats in each transect. Bare ground was determined by counting and recording the distance between tufts within each quadrat. Litter cover was determined by visual observation and rated on a scale of 1 to 5. A number of physical and chemical soil properties were used to quantify the effects of degradation on soil quality. To determine soil chemical properties, three soil samples were collected at a depth of 20 cm, in each plot and analyzed for pH, soil macro (N, C, K, P, Ca, Mg) and micro (Zn, Fe, Mn and Cu) nutrients. Soil compaction was determined using a soil pocket penetrometer. Readings were taken at 5 mm from 30 points placed at 1 m intervals and distributed in a randomly established straight line in each plot. Soil loss was determined using a rainfall simulator. Splash cups were filled with soil and placed under the rainfall simulator for 8 minutes per rainstorm at 360 mm-1 intensity. Results showed that at Esigingqini a total of 20 herbaceous species were identified, 17 of which were grasses. About 60percent of the identified grasses were Increaser II species, 15percent were Increaser II and 25percent Decreasers. In terms of palatability, 50percent of the grass species had poor palatability and the remaining had either average or high palatability. At Kwezana, 18 herbaceous species were identified of which 28percent were Decreasers and 61percent were Increaser II species. Half of the species had low palatability and only 28percent had high palatability. In both communal areas, litter cover was highest (P < 0.05) in the non-degraded areas followed by the slightly degraded sites and this was to be expected. Similarly, in both communal areas, there was a shift in species composition of decreasers and perennial grasses being replaced by annual species of poor quality and low palatability as the degradation levels increased. Results on soil chemical properties showed that the non-degraded areas had higher (P < 0.05) pH levels (8.5) than the severely degraded soils (5). A similar trend following a degradation gradient was observed for some soil nutrients such as N, P or Mg. Both the macro and micro nutrient concentrations were relatively higher (P < 0.05) in summer than in winter in both communal areas. Results on physical properties showed that soil loss and compaction were relatively lower (P <0.05) in the slightly degraded and non-degraded sites and increased with severity of degradation. In both communal areas, the severely degraded areas lost soil up to 1.1 t ha-1 due to degradation and the non-degraded areas had a soil loss of less than 0.8 t ha-1. The rate of soil loss between the severely and non-degraded areas is significantly different. The differences may be attributed to the differences in the vegetation cover which influences the rate of erosion on the various degradation gradients. These results suggest that both the grass layer and soil quality is negatively affected by degradation. Therefore, there is a need for land use practices that promote the sustainable use of rangeland resources. Such practices may include rotational grazing, reseeding, veld resting and fire. Measures to control the consequences of degradation and rehabilitate these deteriorated rangelands must be a priority.
- Full Text:
- Date Issued: 2017
The evaluation of growth characteristics, biomass yield, and chemical composition of two cultivars of Panicum maximum (Mombaca and Gatton) and Brachiaria brizantha (Marandu) at different harvesting stages
- Sokupa, Mihle Inga https://orcid.org/0000-0002-3918-1393
- Authors: Sokupa, Mihle Inga https://orcid.org/0000-0002-3918-1393
- Date: 2020-11
- Subjects: Pastures
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/21433 , vital:48621
- Description: The objective of this study was to carry out a comparative assessment of growth characteristics, biomass yield and chemical composition of Panicum maximum and Brachiaria brizantha cultivars at different harvesting stages. The field experiment was conducted at the University of Fort Hare research farm in Alice, South Africa. The main factors were three cultivars: Mombaca, Gatton (Panicum maximum) and Marandu (Brachiaria brizantha) and three harvesting stages (6, 10 and 14 weeks after planting). This study was a 3 × 3 factorial set up in a randomized complete block design with three replicates. Characteristics which included plant height, number of leaves and number of tillers were measured in five plants per plot at 2-week intervals from 4 to 14 weeks after planting (WAP). The fresh yield was weighed then oven dried at 65oC for 72 hours then dry matter yield was calculated after drying. The chemical composition (Ash, Fat, ADF, ADL, NDF, CP, Ca, Mg, Na, P, K, Cu, Fe, Zn and Mn) was determined on forage harvested at 6, 10 and 14WAP. Data was analysed using the Statistical Analysis Software in a 3x3 factorial to compute the ANOVA and all means of all treatments were calculated and the difference was tested for significance using the Least Significant Difference (LSD) test at P=0.05. The results showed variations (P<0.05) in plant height, but the number of leaves did not differ (P > 0.05) between the cultivars. The number of tillers were significantly different (P<0.05), the highest number of tillers was observed in Mombaca. Fresh yield showed significant differences at 10 and 14WAP, with Marandu producing the highest Fresh yield. The moisture content was different (P<0.05) across all the three harvests. Varying (P< 0.05) results were also observed in the dry matter yield of the cultivars with Mombaca producing the highest dry matter yield. There were no significant differences (P>0.05) in the ash content of the cultivars. The fat content also showed no significant differences. Variations (P<0.05) occured in the ADF of the cultivars, Marandu had the lowest ADF. The cultivar × WAP interactive effect was significant for ADL content. NDF significantly varied across the cultivars at 6WAP. There were no similarities (P<0.05) in the crude protein during the three harvesting intervals, Mombaca produced the highest CP and the lowest was obtained from Gatton. There was a significant interaction (P<0.05) between the cultivars and harvesting intervals for Calcium (Ca), Magnesium (Mg), Sodium (Na), Potassium (K), K/Ca+Mg, Copper (Cu), Iron (Fe), Zinc (Zn) and Manganese (Mn) contents of the cultivars. However, Phosphorus (P) showed no significant interaction (P>0.05) between the cultivars and harvesting intervals. The results obtained in this study showed that as the grasses grow, the biomass yield produced increases according to the genetic makeup and the factors affecting growth and biomass yield. However, the chemical composition decreased between cultivars. Mombaca showed superior traits in terms of growth biomass yield and chemical composition. Mombaca, which is a Panicum maximum cultivar can be used as a choice in forage production and chemical composition as it can supply both quality and quantity. It can be concluded that there are significant differences in growth characteristics, biomass yield and chemical composition of Panicum maximum and Brachiaria brizantha cultivars at different harvesting stages. It can also be recommended that the best harvesting stage is at 10 WAP, this is because both biomass yield and chemical composition are both satisfactory. , Thesis (MSc) -- Faculty of Science and Agriculture, 2020
- Full Text:
- Date Issued: 2020-11
- Authors: Sokupa, Mihle Inga https://orcid.org/0000-0002-3918-1393
- Date: 2020-11
- Subjects: Pastures
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/21433 , vital:48621
- Description: The objective of this study was to carry out a comparative assessment of growth characteristics, biomass yield and chemical composition of Panicum maximum and Brachiaria brizantha cultivars at different harvesting stages. The field experiment was conducted at the University of Fort Hare research farm in Alice, South Africa. The main factors were three cultivars: Mombaca, Gatton (Panicum maximum) and Marandu (Brachiaria brizantha) and three harvesting stages (6, 10 and 14 weeks after planting). This study was a 3 × 3 factorial set up in a randomized complete block design with three replicates. Characteristics which included plant height, number of leaves and number of tillers were measured in five plants per plot at 2-week intervals from 4 to 14 weeks after planting (WAP). The fresh yield was weighed then oven dried at 65oC for 72 hours then dry matter yield was calculated after drying. The chemical composition (Ash, Fat, ADF, ADL, NDF, CP, Ca, Mg, Na, P, K, Cu, Fe, Zn and Mn) was determined on forage harvested at 6, 10 and 14WAP. Data was analysed using the Statistical Analysis Software in a 3x3 factorial to compute the ANOVA and all means of all treatments were calculated and the difference was tested for significance using the Least Significant Difference (LSD) test at P=0.05. The results showed variations (P<0.05) in plant height, but the number of leaves did not differ (P > 0.05) between the cultivars. The number of tillers were significantly different (P<0.05), the highest number of tillers was observed in Mombaca. Fresh yield showed significant differences at 10 and 14WAP, with Marandu producing the highest Fresh yield. The moisture content was different (P<0.05) across all the three harvests. Varying (P< 0.05) results were also observed in the dry matter yield of the cultivars with Mombaca producing the highest dry matter yield. There were no significant differences (P>0.05) in the ash content of the cultivars. The fat content also showed no significant differences. Variations (P<0.05) occured in the ADF of the cultivars, Marandu had the lowest ADF. The cultivar × WAP interactive effect was significant for ADL content. NDF significantly varied across the cultivars at 6WAP. There were no similarities (P<0.05) in the crude protein during the three harvesting intervals, Mombaca produced the highest CP and the lowest was obtained from Gatton. There was a significant interaction (P<0.05) between the cultivars and harvesting intervals for Calcium (Ca), Magnesium (Mg), Sodium (Na), Potassium (K), K/Ca+Mg, Copper (Cu), Iron (Fe), Zinc (Zn) and Manganese (Mn) contents of the cultivars. However, Phosphorus (P) showed no significant interaction (P>0.05) between the cultivars and harvesting intervals. The results obtained in this study showed that as the grasses grow, the biomass yield produced increases according to the genetic makeup and the factors affecting growth and biomass yield. However, the chemical composition decreased between cultivars. Mombaca showed superior traits in terms of growth biomass yield and chemical composition. Mombaca, which is a Panicum maximum cultivar can be used as a choice in forage production and chemical composition as it can supply both quality and quantity. It can be concluded that there are significant differences in growth characteristics, biomass yield and chemical composition of Panicum maximum and Brachiaria brizantha cultivars at different harvesting stages. It can also be recommended that the best harvesting stage is at 10 WAP, this is because both biomass yield and chemical composition are both satisfactory. , Thesis (MSc) -- Faculty of Science and Agriculture, 2020
- Full Text:
- Date Issued: 2020-11
Consumer perceptions and microbial quality of meat sold in the informal markets of Nkonkobe and Buffalo City municipalities in the Eastern province, South Africa
- Authors: Mazizi, Bulelani Elvis
- Date: 2016
- Subjects: Meat -- Quality -- South Africa --Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15365 , vital:40401
- Description: The main objective of the study was to determine consumer perceptions and microbial quality of meat sold in the informal markets found in Nkonkobe and Buffalo City Municipalities in the Eastern Cape Province, South Africa. To determine consumer perceptions of the quality of the meat and meat products sold in the informal markets in Nkonkobe and Buffalo City Municipalities, a survey was conducted. A total of 160 consumers from two municipalities in the Eastern Cape (EC) Province of South Africa was randomly sampled and interviewed. A questionnaire was used to gather information about consumer perceptions of meat and meat products sold in the informal markets regarding their knowledge about safety, food-borne diseases, hygiene, and the quality of the meat among others. The study showed that Alice Town has a larger (66.25percent) proportion of consumers with knowledge about foodborne diseases while King Williams’s Town had a larger proportion (48.75percent) of respondents who had no knowledge about Food-borne diseases. However, a large proportion of consumers in King Williams’s Town considered vendor (82.5percent) and environmental hygiene (93.75percent) than in Alice Town. Consumers (83.75percent) in King Williams’s Town viewed the meat from street vendors to be of low quality while a small proportion (18.75percent) of consumers in Alice Town viewed it as the meat of good quality. Alice had a large proportion (61.25percent) of consumers, which had knowledge of the meat safety law than King Williams’s Town. More consumers from King Williams’s Town (31.25percent) agreed that government plays a role while Alice had a small proportion (26.25percent) which disagreed. The results also showed that consumer perceptions about the safety of meat and meat products are focused more on hygiene, neglecting other important aspects such as vending infrastructure. However, most consumers do not have enough knowledge concerning meat safety. The second study determined the microbial quality of meat sold by street vendors based in Alice and Kind Williams Town in the Eastern Cape Province South Africa. A total of 48 fresh and uncooked meat samples (beef, pork, and mutton), 48 surface contact plates and 40 water samples was collected from 4 street vendors from each town for microbial analysis (n=48). After collection, all samples were subjected to Aerobic plate count (APC), Salmonella spp, Staphylococcus aureus (Staph) and Escherichia coli (E. coli). The results revealed that Salmonella spp tested negative across all the meat samples used in the study. However, no significant differences were found in the microbial quality of meat sold by street vendors in Alice and King Williams town. Furthermore, there were no significant differences (P>0.05) between the APC of raw beef (4.8 Log CFU/g), mutton (3.7 Log CFU/g) and pork (2.8 Log CFU/g) and also the cooked beef (1.5 Log CFU/g), mutton (1.3 Log CFU/g) and pork (1.9 Log CFU/g) samples. A similar trend was observed in the values of Staphylococcus aureus (Staph) and Escherichia coli (E. coli) counts in raw and cooked meat samples. However, a positive correlation between Aerobic plate counts (APC) and Staphylococcus aureus (Staph) (P<0.001) and Escherichia coli (E. coli) (P<0.01) was found in the study. It can, therefore, be concluded that there were no differences in the microbial counts of raw and cooked meat sold in the informal markets of Nkonkobe and Buffalo City Municipalities in the Eastern Cape Province, South Africa.
- Full Text:
- Date Issued: 2016
- Authors: Mazizi, Bulelani Elvis
- Date: 2016
- Subjects: Meat -- Quality -- South Africa --Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15365 , vital:40401
- Description: The main objective of the study was to determine consumer perceptions and microbial quality of meat sold in the informal markets found in Nkonkobe and Buffalo City Municipalities in the Eastern Cape Province, South Africa. To determine consumer perceptions of the quality of the meat and meat products sold in the informal markets in Nkonkobe and Buffalo City Municipalities, a survey was conducted. A total of 160 consumers from two municipalities in the Eastern Cape (EC) Province of South Africa was randomly sampled and interviewed. A questionnaire was used to gather information about consumer perceptions of meat and meat products sold in the informal markets regarding their knowledge about safety, food-borne diseases, hygiene, and the quality of the meat among others. The study showed that Alice Town has a larger (66.25percent) proportion of consumers with knowledge about foodborne diseases while King Williams’s Town had a larger proportion (48.75percent) of respondents who had no knowledge about Food-borne diseases. However, a large proportion of consumers in King Williams’s Town considered vendor (82.5percent) and environmental hygiene (93.75percent) than in Alice Town. Consumers (83.75percent) in King Williams’s Town viewed the meat from street vendors to be of low quality while a small proportion (18.75percent) of consumers in Alice Town viewed it as the meat of good quality. Alice had a large proportion (61.25percent) of consumers, which had knowledge of the meat safety law than King Williams’s Town. More consumers from King Williams’s Town (31.25percent) agreed that government plays a role while Alice had a small proportion (26.25percent) which disagreed. The results also showed that consumer perceptions about the safety of meat and meat products are focused more on hygiene, neglecting other important aspects such as vending infrastructure. However, most consumers do not have enough knowledge concerning meat safety. The second study determined the microbial quality of meat sold by street vendors based in Alice and Kind Williams Town in the Eastern Cape Province South Africa. A total of 48 fresh and uncooked meat samples (beef, pork, and mutton), 48 surface contact plates and 40 water samples was collected from 4 street vendors from each town for microbial analysis (n=48). After collection, all samples were subjected to Aerobic plate count (APC), Salmonella spp, Staphylococcus aureus (Staph) and Escherichia coli (E. coli). The results revealed that Salmonella spp tested negative across all the meat samples used in the study. However, no significant differences were found in the microbial quality of meat sold by street vendors in Alice and King Williams town. Furthermore, there were no significant differences (P>0.05) between the APC of raw beef (4.8 Log CFU/g), mutton (3.7 Log CFU/g) and pork (2.8 Log CFU/g) and also the cooked beef (1.5 Log CFU/g), mutton (1.3 Log CFU/g) and pork (1.9 Log CFU/g) samples. A similar trend was observed in the values of Staphylococcus aureus (Staph) and Escherichia coli (E. coli) counts in raw and cooked meat samples. However, a positive correlation between Aerobic plate counts (APC) and Staphylococcus aureus (Staph) (P<0.001) and Escherichia coli (E. coli) (P<0.01) was found in the study. It can, therefore, be concluded that there were no differences in the microbial counts of raw and cooked meat sold in the informal markets of Nkonkobe and Buffalo City Municipalities in the Eastern Cape Province, South Africa.
- Full Text:
- Date Issued: 2016
A study of the selected wild edible plants utilized by indigenous people of the Amathole District in the Eastern Cape Province of South Africa
- Kwinana-Mandindi, Thozama Ndileka
- Authors: Kwinana-Mandindi, Thozama Ndileka
- Date: 2012
- Subjects: Wild plants, Edible http://id.loc.gov/authorities/subjects/sh85146686
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/19598 , vital:43147
- Description: Wild edible plants are an indispensible part of diets in some of the poor resourced rural societies. In many less resourced households a main meal comprises of a starch staple which is accompanied by a supplement of vegetables that provide the other nutritional elements as well as flavour to the meals. The vegetable relish (isishebo) thus, becomes an important component of the diet. The sustenance of many such resource poor indigenous societies over many generations has been as a result of their reliance on a readily available supply of their nutritional requirements, where edible wild plants formed the major food source. Wild edible plants provided the most important source of nutritional supply even during times of drought and famine. However, lifestyle changes have caused a serious reduction of the gathering and use of the wild edible vegetables, knowledge about them and the local culture are also lost with them. Unfortunately, others have come to regard their traditional food resource base as primitive and inferior and have come to rely on new exotic food plant whose supply is unstable and narrow compared to the wide variety of wild edible plants. Even when drought challenges play destruction with food availability, resulting in food shortages due to the reliance on cultivated crops that are poorly adapted to local conditions, communities cannot go back to the unknown food plants. However, detailed scientific investigations are needed to understand and preserve wild food uses. This study was undertaken to add to that body of knowledge. It started with an ethnobotanic survey of the use of wild food plants in 10 selected rural villages and peri-urban dwellings in the Amathole District of the Eastern Cape. These rural areas were chosen because of the belief that there are still individuals who possess the wealth of traditional knowledge within those remote areas in addition to that the villages are surrounded by indigenous vegetation from which they could be harvesting some indigenous food plants. Furthermore, the relationship between people and plants are often clearer in indigenous/traditional societies since the link between production and consumption is more direct. Besides the survey, this research employed various methods including Inductively Coupled Argon (ICP) analyses of minerals and vitamins, determination of phytochemicals and antioxidant/bio-activity that of, higher performance liquid chromatography (HPLC) determination of other vitamins, assessment of proximate and anti-nutrient compositions of raw and cooked samples of plants, scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDXS) to look into the micro-morphology of leaves for details that might have a bearing in the nutrient composition of the wild edible vegetables. This was done with the aim to explore and highlight the wild-food-plant base of indigenous people, to investigate the nutritional value of the selected frequently consumed wild vegetables and to recommend ways of educating people on the value of such plants and the need to promote their continued sustainable use as well as preservation of them for the benefit of people who cannot afford a continuous nutritious meal particularly among rural communities. Twenty-five (25) indigenous wild food plants which included leafy vegetables, nuts and fruits species were identified as being arbitrarily gathered and utilised as food, of which seven wild leafy vegetable species were often mentioned as common among the 15 dwellings surveyed and most frequently consumed by the respondents. Two additional plants were also frequently used as flavoring and in their raw state respectively. Wild edible vegetables were mainly eaten boiled as ‘laxa’, mixed with maize meal as ‘imifino’, fried as relish ‘isishebo’ or raw for both snacking purposes and medicinal functions. Wild edible plant species in the Amathole District of the Eastern Cape-South Africa were documented with respect to their uses and knowledge or identification. Four indigenous wild vegetables (Chenopodium album, Solanum nigrum/nodiflorum, Amaranthus dubius and Urtica lobulata) frequently consumed by the indigenous communities in the study region were selected. All the plant species had a remarkably high content of pro-anthocyanidins (between 58.42 and 65.18 mg/g) and also exhibited high radical scavenging activity in vitro. S. nigrum and C. album were found to be rich sources of ascorbic acid, having 1.05mg/100g and 1.01mg/100g, respectively. The entire wild, traditionally edible plants contain reasonably good concentrations of riboflavin while U. lobulata was found to contain maximum amount of thiamine. All plant species were rich sources of minerals and vitamins (both water soluble and fat soluble). Appropriate cooking methods are to be used to enhance the bio-availability of vitamins and nutrients in general. Cooking generally improved the nutritive value in certain wild vegetables. However, some nutrients were drained away. For example micro-nutrient and anti-nutrient component in the ash were reduced in cooking. The EDXS analysis has shown that the indigenous, wild vegetables in the Amathole District of South Africa are excellent sources of minerals, while the mineral crystals present at the level of the mesophyll of the indigenous wild vegetables were probably mixtures of calcium oxalate, calcium sulphate and silica. Saponin, tannins, oxalates, phytates and alkaloids are present in all the indigenous wild vegetables, but in minimal safe quantities. Nutritional analysis of some wild food plants demonstrates that in many cases the nutritional quality of the plants is comparable and in some cases even superior to domesticated exotic varieties. Knowledge about gathering and use of some wild food species is common among the rural dwellers. However, most uses are known by few elderly informants only. Education, awareness campaigns and revival of use of wild edible plants directed at the youth particularly is essential and this can be done through all forms of media. , Thesis (PhD) (Ethnobotany) -- University of Fort Hare, 2012
- Full Text:
- Date Issued: 2012
- Authors: Kwinana-Mandindi, Thozama Ndileka
- Date: 2012
- Subjects: Wild plants, Edible http://id.loc.gov/authorities/subjects/sh85146686
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/19598 , vital:43147
- Description: Wild edible plants are an indispensible part of diets in some of the poor resourced rural societies. In many less resourced households a main meal comprises of a starch staple which is accompanied by a supplement of vegetables that provide the other nutritional elements as well as flavour to the meals. The vegetable relish (isishebo) thus, becomes an important component of the diet. The sustenance of many such resource poor indigenous societies over many generations has been as a result of their reliance on a readily available supply of their nutritional requirements, where edible wild plants formed the major food source. Wild edible plants provided the most important source of nutritional supply even during times of drought and famine. However, lifestyle changes have caused a serious reduction of the gathering and use of the wild edible vegetables, knowledge about them and the local culture are also lost with them. Unfortunately, others have come to regard their traditional food resource base as primitive and inferior and have come to rely on new exotic food plant whose supply is unstable and narrow compared to the wide variety of wild edible plants. Even when drought challenges play destruction with food availability, resulting in food shortages due to the reliance on cultivated crops that are poorly adapted to local conditions, communities cannot go back to the unknown food plants. However, detailed scientific investigations are needed to understand and preserve wild food uses. This study was undertaken to add to that body of knowledge. It started with an ethnobotanic survey of the use of wild food plants in 10 selected rural villages and peri-urban dwellings in the Amathole District of the Eastern Cape. These rural areas were chosen because of the belief that there are still individuals who possess the wealth of traditional knowledge within those remote areas in addition to that the villages are surrounded by indigenous vegetation from which they could be harvesting some indigenous food plants. Furthermore, the relationship between people and plants are often clearer in indigenous/traditional societies since the link between production and consumption is more direct. Besides the survey, this research employed various methods including Inductively Coupled Argon (ICP) analyses of minerals and vitamins, determination of phytochemicals and antioxidant/bio-activity that of, higher performance liquid chromatography (HPLC) determination of other vitamins, assessment of proximate and anti-nutrient compositions of raw and cooked samples of plants, scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDXS) to look into the micro-morphology of leaves for details that might have a bearing in the nutrient composition of the wild edible vegetables. This was done with the aim to explore and highlight the wild-food-plant base of indigenous people, to investigate the nutritional value of the selected frequently consumed wild vegetables and to recommend ways of educating people on the value of such plants and the need to promote their continued sustainable use as well as preservation of them for the benefit of people who cannot afford a continuous nutritious meal particularly among rural communities. Twenty-five (25) indigenous wild food plants which included leafy vegetables, nuts and fruits species were identified as being arbitrarily gathered and utilised as food, of which seven wild leafy vegetable species were often mentioned as common among the 15 dwellings surveyed and most frequently consumed by the respondents. Two additional plants were also frequently used as flavoring and in their raw state respectively. Wild edible vegetables were mainly eaten boiled as ‘laxa’, mixed with maize meal as ‘imifino’, fried as relish ‘isishebo’ or raw for both snacking purposes and medicinal functions. Wild edible plant species in the Amathole District of the Eastern Cape-South Africa were documented with respect to their uses and knowledge or identification. Four indigenous wild vegetables (Chenopodium album, Solanum nigrum/nodiflorum, Amaranthus dubius and Urtica lobulata) frequently consumed by the indigenous communities in the study region were selected. All the plant species had a remarkably high content of pro-anthocyanidins (between 58.42 and 65.18 mg/g) and also exhibited high radical scavenging activity in vitro. S. nigrum and C. album were found to be rich sources of ascorbic acid, having 1.05mg/100g and 1.01mg/100g, respectively. The entire wild, traditionally edible plants contain reasonably good concentrations of riboflavin while U. lobulata was found to contain maximum amount of thiamine. All plant species were rich sources of minerals and vitamins (both water soluble and fat soluble). Appropriate cooking methods are to be used to enhance the bio-availability of vitamins and nutrients in general. Cooking generally improved the nutritive value in certain wild vegetables. However, some nutrients were drained away. For example micro-nutrient and anti-nutrient component in the ash were reduced in cooking. The EDXS analysis has shown that the indigenous, wild vegetables in the Amathole District of South Africa are excellent sources of minerals, while the mineral crystals present at the level of the mesophyll of the indigenous wild vegetables were probably mixtures of calcium oxalate, calcium sulphate and silica. Saponin, tannins, oxalates, phytates and alkaloids are present in all the indigenous wild vegetables, but in minimal safe quantities. Nutritional analysis of some wild food plants demonstrates that in many cases the nutritional quality of the plants is comparable and in some cases even superior to domesticated exotic varieties. Knowledge about gathering and use of some wild food species is common among the rural dwellers. However, most uses are known by few elderly informants only. Education, awareness campaigns and revival of use of wild edible plants directed at the youth particularly is essential and this can be done through all forms of media. , Thesis (PhD) (Ethnobotany) -- University of Fort Hare, 2012
- Full Text:
- Date Issued: 2012
Cost and return analysis of smallholder organic crop farms in the Eastern Cape province of South Africa
- Authors: Akharume, Celestine Ohi
- Date: 2017
- Subjects: Farms, Small -- South Africa -- Eastern Cape Profit -- South Africa -- Eastern Cape Organic farming -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MAgric
- Identifier: http://hdl.handle.net/10353/13730 , vital:39703
- Description: Agriculture remains an influential sector in South Africa in terms of its contributions to economic development and poverty reduction, notably in the rural areas. These include providing sufficient and affordable food for the constantly increasing population, providing cheap food for the developing industrial labor force, providing employment and livelihoods and supplying raw materials to the country’s rising domestic industrial sector. Despite phenomenal progress in integrating smallholder farmers into the mainstream economy since democratic reforms in the country, deteriorating soil quality through poor agricultural practices, land erosion, acidification and concerns about production and productivity and compliance with food safety standards are beginning to loom high. Hence, organic farming is identified as one of the sustainable approaches to farming. It is also believed to guarantee substantial net gains and to promote sustainable natural resource management with the possibility of enhancing overall agricultural productivity. Notwithstanding, organic farming is still being perceived negatively in South Africa and there is shortage of empirical studies which focus on cost and return of smallholder organic crop farms. It is in this regard that the study therefore seeks to analyze cost and return of smallholder organic crop farms in the Eastern Cape Province to contribute to knowledge on the relative economic advantages of organic agriculture at the smallholder sector. Specifically, the study profiled the socioeconomic characteristics of smallholder organic crop farmers, determined costs and returns, and estimated profitability and factors that constrain profitability of the smallholder organic crop farms. The research design used in this study was cross-sectional where data were collected at a single point in time. A multi- stage random sampling technique was used to obtain primary data from one hundred and sixty smallholder organic crop farmers (160) with the aid of structured questionnaires. Primary data were collected on demographic and socioeconomic characteristics, variable costs and fixed costs, and returns from the organic crop farms. Data collected were analyzed by Statistical Package for Social Sciences (SPSS) and the descriptive and inferential statistics involved were mean, frequency proportion, gross margin and net income analysis as well as OLS regression analysis. The results of the descriptive analysis showed that the proportions of women involved in organic crop farming were higher than that of men and many of the farmers cultivated on less than 1.0ha. The analysis of the data also showed that smallholder organic crop farms are undoubtedly profitable farm business, with attractive net farm income and lower production costs. The findings further affirmed that factors such as household size, gender, farming experience, number of years in school, farm size, source of labor and access to credit affect profitability and net farm income. Therefore, government is advised to encourage the practice of organic farming by giving short-term loans to smallholder farmers, to enable them invest more in their organic crop farms. There is also need for government to organize workshops and lectures, educating and enlightening individual smallholder organic crop farmers on modern organic farming techniques to enhance profitability of smallholder organic crop farms.
- Full Text:
- Date Issued: 2017
- Authors: Akharume, Celestine Ohi
- Date: 2017
- Subjects: Farms, Small -- South Africa -- Eastern Cape Profit -- South Africa -- Eastern Cape Organic farming -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MAgric
- Identifier: http://hdl.handle.net/10353/13730 , vital:39703
- Description: Agriculture remains an influential sector in South Africa in terms of its contributions to economic development and poverty reduction, notably in the rural areas. These include providing sufficient and affordable food for the constantly increasing population, providing cheap food for the developing industrial labor force, providing employment and livelihoods and supplying raw materials to the country’s rising domestic industrial sector. Despite phenomenal progress in integrating smallholder farmers into the mainstream economy since democratic reforms in the country, deteriorating soil quality through poor agricultural practices, land erosion, acidification and concerns about production and productivity and compliance with food safety standards are beginning to loom high. Hence, organic farming is identified as one of the sustainable approaches to farming. It is also believed to guarantee substantial net gains and to promote sustainable natural resource management with the possibility of enhancing overall agricultural productivity. Notwithstanding, organic farming is still being perceived negatively in South Africa and there is shortage of empirical studies which focus on cost and return of smallholder organic crop farms. It is in this regard that the study therefore seeks to analyze cost and return of smallholder organic crop farms in the Eastern Cape Province to contribute to knowledge on the relative economic advantages of organic agriculture at the smallholder sector. Specifically, the study profiled the socioeconomic characteristics of smallholder organic crop farmers, determined costs and returns, and estimated profitability and factors that constrain profitability of the smallholder organic crop farms. The research design used in this study was cross-sectional where data were collected at a single point in time. A multi- stage random sampling technique was used to obtain primary data from one hundred and sixty smallholder organic crop farmers (160) with the aid of structured questionnaires. Primary data were collected on demographic and socioeconomic characteristics, variable costs and fixed costs, and returns from the organic crop farms. Data collected were analyzed by Statistical Package for Social Sciences (SPSS) and the descriptive and inferential statistics involved were mean, frequency proportion, gross margin and net income analysis as well as OLS regression analysis. The results of the descriptive analysis showed that the proportions of women involved in organic crop farming were higher than that of men and many of the farmers cultivated on less than 1.0ha. The analysis of the data also showed that smallholder organic crop farms are undoubtedly profitable farm business, with attractive net farm income and lower production costs. The findings further affirmed that factors such as household size, gender, farming experience, number of years in school, farm size, source of labor and access to credit affect profitability and net farm income. Therefore, government is advised to encourage the practice of organic farming by giving short-term loans to smallholder farmers, to enable them invest more in their organic crop farms. There is also need for government to organize workshops and lectures, educating and enlightening individual smallholder organic crop farmers on modern organic farming techniques to enhance profitability of smallholder organic crop farms.
- Full Text:
- Date Issued: 2017
Molecular characterization of Mycobacterium bovis isolated from cattle and sputum specimens from humans in the Eastern Cape province, South Africa : public health and economic implication
- Authors: Bhembe, Nolwazi Londiwe
- Date: 2016
- Subjects: Mycobacterium tuberculosis -- South Africa -- Eastern Cape Public health -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/13238 , vital:39625
- Description: Tuberculosis (TB) is a disease caused by the members of the Mycobacterium tuberculosis complex (MTBC), which infects both animals and humans. The primary host of Mycobacterium bovis is cattle. It remains a major global health problem. About 2 billion people are thought to be infected with TB and about 1.3 million decease each year from the disease. This study is aimed at determining the prevalence of the disease, characterizing the MTBC isolates and increasing the understanding of the genetic diversity MTBC in the Eastern Cape Province of South Africa, from studying both samples from both humans and cattle. A total of 376 cattle lymph nodes were collected from two commercial abattoirs for investigations. Suspected 6 000 sputum specimens were also collected from humans (cattle farmers). All collected samples were cultured, and isolates were confirmed with a multiplex polymerase chain reaction (PCR) targeting the mpb64 and IS6110 genes. Positive isolates were tested for resistance against anti-TB drugs using the standard Lowenstein Jensen proportion method. Isolates from cattle lymph nodes were further characterized to species level, using the region of deletion 1 (RD1) and oxyR restriction fragment length polymorphism analyses. MIRU-VNTR typing and spoligotyping assays were used to further examine the genetic diversity of all strains. Obtained spoligotype patterns were matched with isolates published in the universal spoligotyping database (SITVIT2). MTBC was detected in 162 (43.09 percent) cattle lymph nodes and 156 sputum specimens. Some isolates 25.9 percent (42/162) from the cattle lymph nodes samples were resistant to rifampicin (RIF) and 98.7 percent (154/156) were resistant to isoniazid (INH) and rifampicin (RIF) (of the human sputum specimens). All cattle lymph nodes isolates exhibited the RD1 gene, and the oxyR analyses classified 96.9 percent of the isolates as Mycobacterium tuberculosis complex and 3.1 percent as Mycobacterium bovis. Twenty seven spoligotype patterns were isolated from cattle lymph nodes, with 10 shared types (SIT) consigned to 5 lineages, including Bov_4-Caprea (1.9 percent), Microti (0.6 percent) and Beijing (17.9 percent) constituting East Asian, Latin-American-Mediterranean (LAM) (3.7 percent), X (4.3 percent), MANU (3.1percent), S (0.6 percent) and 67.9 percent were orphans that were further categorized to their designated lineages (Indo-Oceanic, Euro-American and West-African 2). Ninety one percent of the isolates from humans (farmers) were grouped into 7 clusters by spoligotyping, while the remaining 9 percent was unclustered. SITs were observed in 89.6 percent of the isolates from the Beijing, LAM, X, T and S families. The Beijing family was the most prevalent strain from both human isolates (77.2 percent) and cattle lymph nodes isolates (17.9 percent), and the T (0.6 percent) and Microti (0.6 percent) families were the least detected genotypes in both humans and cattle lymph nodes. In the cattle lymph nodes, spoligotyping showed a higher clustering rate of 82.1 percent, with the lowest (HGDI) = 0.485. The 12 MIRU-VNTR clustering rate was 64.8 percent, showing a higher HGDI of 0.671. However, a combination of both methods showed a decreased clustering rate of 53.7 percent; however these methods resulted in a higher HGDI (0.676). Isolates from human sputum specimens spoligotyping showed a higher clustering rate of 89 percent with an HGDI = 0.822. The 12 MIRU-VNTR showed the lowest clustering rate of 69 percent and an HGDI = 0.940 and the combination of the methods showed a clustering rate of 78 percent and an HGDI = 0.951. The results of this study show the diversity of MTBC strains in the Eastern Cape Province and the low clustering rate indicates continuing transmission in the province. The detection of MTBC strains from slaughtered cattle lymph nodes in abattoirs confirms the risk of providing TB infected meat in markets which has serious implications for the control of TB in South Africa. The continuing spread of MTBC in South Africa threatens both the public and economic health.
- Full Text:
- Date Issued: 2016
- Authors: Bhembe, Nolwazi Londiwe
- Date: 2016
- Subjects: Mycobacterium tuberculosis -- South Africa -- Eastern Cape Public health -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/13238 , vital:39625
- Description: Tuberculosis (TB) is a disease caused by the members of the Mycobacterium tuberculosis complex (MTBC), which infects both animals and humans. The primary host of Mycobacterium bovis is cattle. It remains a major global health problem. About 2 billion people are thought to be infected with TB and about 1.3 million decease each year from the disease. This study is aimed at determining the prevalence of the disease, characterizing the MTBC isolates and increasing the understanding of the genetic diversity MTBC in the Eastern Cape Province of South Africa, from studying both samples from both humans and cattle. A total of 376 cattle lymph nodes were collected from two commercial abattoirs for investigations. Suspected 6 000 sputum specimens were also collected from humans (cattle farmers). All collected samples were cultured, and isolates were confirmed with a multiplex polymerase chain reaction (PCR) targeting the mpb64 and IS6110 genes. Positive isolates were tested for resistance against anti-TB drugs using the standard Lowenstein Jensen proportion method. Isolates from cattle lymph nodes were further characterized to species level, using the region of deletion 1 (RD1) and oxyR restriction fragment length polymorphism analyses. MIRU-VNTR typing and spoligotyping assays were used to further examine the genetic diversity of all strains. Obtained spoligotype patterns were matched with isolates published in the universal spoligotyping database (SITVIT2). MTBC was detected in 162 (43.09 percent) cattle lymph nodes and 156 sputum specimens. Some isolates 25.9 percent (42/162) from the cattle lymph nodes samples were resistant to rifampicin (RIF) and 98.7 percent (154/156) were resistant to isoniazid (INH) and rifampicin (RIF) (of the human sputum specimens). All cattle lymph nodes isolates exhibited the RD1 gene, and the oxyR analyses classified 96.9 percent of the isolates as Mycobacterium tuberculosis complex and 3.1 percent as Mycobacterium bovis. Twenty seven spoligotype patterns were isolated from cattle lymph nodes, with 10 shared types (SIT) consigned to 5 lineages, including Bov_4-Caprea (1.9 percent), Microti (0.6 percent) and Beijing (17.9 percent) constituting East Asian, Latin-American-Mediterranean (LAM) (3.7 percent), X (4.3 percent), MANU (3.1percent), S (0.6 percent) and 67.9 percent were orphans that were further categorized to their designated lineages (Indo-Oceanic, Euro-American and West-African 2). Ninety one percent of the isolates from humans (farmers) were grouped into 7 clusters by spoligotyping, while the remaining 9 percent was unclustered. SITs were observed in 89.6 percent of the isolates from the Beijing, LAM, X, T and S families. The Beijing family was the most prevalent strain from both human isolates (77.2 percent) and cattle lymph nodes isolates (17.9 percent), and the T (0.6 percent) and Microti (0.6 percent) families were the least detected genotypes in both humans and cattle lymph nodes. In the cattle lymph nodes, spoligotyping showed a higher clustering rate of 82.1 percent, with the lowest (HGDI) = 0.485. The 12 MIRU-VNTR clustering rate was 64.8 percent, showing a higher HGDI of 0.671. However, a combination of both methods showed a decreased clustering rate of 53.7 percent; however these methods resulted in a higher HGDI (0.676). Isolates from human sputum specimens spoligotyping showed a higher clustering rate of 89 percent with an HGDI = 0.822. The 12 MIRU-VNTR showed the lowest clustering rate of 69 percent and an HGDI = 0.940 and the combination of the methods showed a clustering rate of 78 percent and an HGDI = 0.951. The results of this study show the diversity of MTBC strains in the Eastern Cape Province and the low clustering rate indicates continuing transmission in the province. The detection of MTBC strains from slaughtered cattle lymph nodes in abattoirs confirms the risk of providing TB infected meat in markets which has serious implications for the control of TB in South Africa. The continuing spread of MTBC in South Africa threatens both the public and economic health.
- Full Text:
- Date Issued: 2016
Electrochemical sensing based on functionalised carbon dots prepared by bottom-up approach
- Madikizela, Ziyanda https://orcid.org/0000-0003-0405-8464
- Authors: Madikizela, Ziyanda https://orcid.org/0000-0003-0405-8464
- Date: 2021-02
- Subjects: Electrochemical analysis , Electrodes, Carbon
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/22545 , vital:52424
- Description: This research was aimed at preparing carbon dots using the microwave method as a bottomup synthetic approach. The prepared carbon dots were them to be used as an electrode modifier in electrochemical detection of metal ion. The structure of the carbon dots prepared were characterized using different techniques including the FTIR, TEM, UV-Vis, PL, XRD and Raman Spectroscopy. It was observed that the nanoparticles consisted of carboxylic acid, amine and alcohol functional groups at their core and surface. UV-Vis and PL revealed that the carbon dots absorb more light in the visible and ultraviolet region, and the sizes of the carbon dots prepared were less than 10 nm. The carbon dots were then utilized for electrochemical sensing of Cd2+ ion, which is considered as one of harmful heavy metal ion when not controlled. Glassy carbon electrode modified with the carbon dots was utilized for the detection of Cd2+ through square wave voltammetry. Effect of different experimental parameters was studied which include electrode preparation, frequency, and amplitude. The electrochemical characterization of the electrode was done using the cyclic voltammetry and electrochemical impedance spectroscopy (EIS), the modified electrode was found conductive with much improved electrochemical performances. The obtained detection limit for Cd2+ sensing was 9.39 ppb, the developed C-dots modified GCE electrode was also tested with tap water Cd2+ spiked solution to demonstrate its implementation in real sample analysis. , Thesis (MA) -- Faculty of Science and Agriculture, 2021
- Full Text:
- Date Issued: 2021-02
- Authors: Madikizela, Ziyanda https://orcid.org/0000-0003-0405-8464
- Date: 2021-02
- Subjects: Electrochemical analysis , Electrodes, Carbon
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/22545 , vital:52424
- Description: This research was aimed at preparing carbon dots using the microwave method as a bottomup synthetic approach. The prepared carbon dots were them to be used as an electrode modifier in electrochemical detection of metal ion. The structure of the carbon dots prepared were characterized using different techniques including the FTIR, TEM, UV-Vis, PL, XRD and Raman Spectroscopy. It was observed that the nanoparticles consisted of carboxylic acid, amine and alcohol functional groups at their core and surface. UV-Vis and PL revealed that the carbon dots absorb more light in the visible and ultraviolet region, and the sizes of the carbon dots prepared were less than 10 nm. The carbon dots were then utilized for electrochemical sensing of Cd2+ ion, which is considered as one of harmful heavy metal ion when not controlled. Glassy carbon electrode modified with the carbon dots was utilized for the detection of Cd2+ through square wave voltammetry. Effect of different experimental parameters was studied which include electrode preparation, frequency, and amplitude. The electrochemical characterization of the electrode was done using the cyclic voltammetry and electrochemical impedance spectroscopy (EIS), the modified electrode was found conductive with much improved electrochemical performances. The obtained detection limit for Cd2+ sensing was 9.39 ppb, the developed C-dots modified GCE electrode was also tested with tap water Cd2+ spiked solution to demonstrate its implementation in real sample analysis. , Thesis (MA) -- Faculty of Science and Agriculture, 2021
- Full Text:
- Date Issued: 2021-02
Diversity, host plant range and ecology of Lepidoptera stem borers in South Africa
- Authors: Stemele, Mxolisi Arnold
- Date: 2019
- Subjects: Lepidoptera Host plants Stem borers
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/15409 , vital:40405
- Description: The biology and ecology of Lepidopteran pests stem borers has been extensively studied because of the economic importance of pest species such as Busseola fusca (Fuller) (Noctuidae), Sesamia calamistis (Hampson) (Noctuidae), Chilo partellus (Swinhoe) (Crambidae), and Eldana saccharina (Walker) (Pyralidae). Knowledge relating to diversity, infestation dynamics, and host plant range is readily available. In natural vegetation, the variety of stem borers is higher than that found in agroecosystems. However, there is a paucity of South African studies that explain the observed differences in diversity between the two systems. Stem borers are also known to exhibit species-specific ecological requirements, which influence their distribution between African countries. South African biomes are classified based on vegetation structure and climate, which happens to be the most critical factors that affect the distribution of phytophagous insects. This makes biomes an excellent model to investigate diversity and distribution of stem borer species. In this study, we investigated diversity, distribution and species composition in four biomes. The results showed that diversity and distribution of the stem borers in natural vegetation was determined by host plant distribution. Stem borer diversity correlated with high diversity of host plants. Thirty-two stem borer species were collected from 27 host plants and another three from light traps. Widely distributed host plants supported a higher diversity of stem borers, which is consistent with the resource availability hypotheses. Non-metric dimensional scale unfolding revealed disparity in host plant preference and plant species composition between the various stem borer families (Kruskal’s Stress = 0.16). Tortricidae species and Sesamia typhae (Le rü) (Noctuidae) feed exclusively on hydrophytic Cyperaceae species. The majority of Noctuidae, Crambidae and Phycitidae species collected were oligophagous on terrestrial Poaceae, with a few polyphagous exceptions feeding on hydrophytic Cyperaceae and Typhaceae. Additionally, species composition of Poaceae host plants differed between 8 Crambidae and the Phycitidae species. Stem borer species composition between biomes revealed the presence of distinct host plants (2D stress = 0.09) and stem borer (2D stress = 0.13) communities. The stem borer abundance and diversity were strongly correlated (R2 = 0.64), but species diversity (R2 = - 0.95) and host plant diversity (R2 = - 0.85) were inversely correlated to altitude. Based on these results it was concluded that stem borer diversity and distribution in natural vegetation was influenced by host plant diversity and distribution as well as climate associated with altitudinal gradients. In the last two decades, four stem borer species previously known on wild host plants; Busseola segeta (Bowden), Busseola phaia (Bowden), Pirateolea piscator (Fletcher) and Conicofrontia sesamoides (Hampson) have invaded cultivated crops. These invasions remained undetected because of a shortage of surveys, habitat transformation and misidentifications. Misidentifications are common among stem borers due to the considerable resemblance between morphospecies. In this study, we assessed the capacity of the mitochondrial gene Cytochrome c oxidase (COI) to delineate closely related species to develop monitoring and early detection of invasive species and to assess migration patterns and gene flow between the populations. The results demonstrated that COI is an effective DNA marker for species delineation and assessment of intra- and interspecific genetic relationship. The K2P distances and phylogenetic tree defined boundaries between Noctuidae species with high resolution. No divergence distance was detected between intraspecific species, but for the congener species, divergence distance was 0.044%-0.111% with an average of 0.076%. The average interspecies K2P distance (0.57%) was 5-15 times higher than the congener species distances. Phylogenetic analysis revealed the presence of two clades. Busseola and Sesamia species were connected in a monophyletic clade with a strong (93%) bootstrap. The second monophyletic clade comprised of a cluster of Pirateolea, Acrapex and Conicofrontia species, and this was also supported with 9 a strong bootstrap (100%). The gene flow study revealed low levels of genetic differentiation between the populations of B. fusca collected from different maize producing areas in South Africa. This low genetic differentiation was consistent with high gene flow. The number of effective migrants between the populations was between 8 and 99 individuals per generation. These results indicate high connectivity between the populations.
- Full Text:
- Date Issued: 2019
- Authors: Stemele, Mxolisi Arnold
- Date: 2019
- Subjects: Lepidoptera Host plants Stem borers
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/15409 , vital:40405
- Description: The biology and ecology of Lepidopteran pests stem borers has been extensively studied because of the economic importance of pest species such as Busseola fusca (Fuller) (Noctuidae), Sesamia calamistis (Hampson) (Noctuidae), Chilo partellus (Swinhoe) (Crambidae), and Eldana saccharina (Walker) (Pyralidae). Knowledge relating to diversity, infestation dynamics, and host plant range is readily available. In natural vegetation, the variety of stem borers is higher than that found in agroecosystems. However, there is a paucity of South African studies that explain the observed differences in diversity between the two systems. Stem borers are also known to exhibit species-specific ecological requirements, which influence their distribution between African countries. South African biomes are classified based on vegetation structure and climate, which happens to be the most critical factors that affect the distribution of phytophagous insects. This makes biomes an excellent model to investigate diversity and distribution of stem borer species. In this study, we investigated diversity, distribution and species composition in four biomes. The results showed that diversity and distribution of the stem borers in natural vegetation was determined by host plant distribution. Stem borer diversity correlated with high diversity of host plants. Thirty-two stem borer species were collected from 27 host plants and another three from light traps. Widely distributed host plants supported a higher diversity of stem borers, which is consistent with the resource availability hypotheses. Non-metric dimensional scale unfolding revealed disparity in host plant preference and plant species composition between the various stem borer families (Kruskal’s Stress = 0.16). Tortricidae species and Sesamia typhae (Le rü) (Noctuidae) feed exclusively on hydrophytic Cyperaceae species. The majority of Noctuidae, Crambidae and Phycitidae species collected were oligophagous on terrestrial Poaceae, with a few polyphagous exceptions feeding on hydrophytic Cyperaceae and Typhaceae. Additionally, species composition of Poaceae host plants differed between 8 Crambidae and the Phycitidae species. Stem borer species composition between biomes revealed the presence of distinct host plants (2D stress = 0.09) and stem borer (2D stress = 0.13) communities. The stem borer abundance and diversity were strongly correlated (R2 = 0.64), but species diversity (R2 = - 0.95) and host plant diversity (R2 = - 0.85) were inversely correlated to altitude. Based on these results it was concluded that stem borer diversity and distribution in natural vegetation was influenced by host plant diversity and distribution as well as climate associated with altitudinal gradients. In the last two decades, four stem borer species previously known on wild host plants; Busseola segeta (Bowden), Busseola phaia (Bowden), Pirateolea piscator (Fletcher) and Conicofrontia sesamoides (Hampson) have invaded cultivated crops. These invasions remained undetected because of a shortage of surveys, habitat transformation and misidentifications. Misidentifications are common among stem borers due to the considerable resemblance between morphospecies. In this study, we assessed the capacity of the mitochondrial gene Cytochrome c oxidase (COI) to delineate closely related species to develop monitoring and early detection of invasive species and to assess migration patterns and gene flow between the populations. The results demonstrated that COI is an effective DNA marker for species delineation and assessment of intra- and interspecific genetic relationship. The K2P distances and phylogenetic tree defined boundaries between Noctuidae species with high resolution. No divergence distance was detected between intraspecific species, but for the congener species, divergence distance was 0.044%-0.111% with an average of 0.076%. The average interspecies K2P distance (0.57%) was 5-15 times higher than the congener species distances. Phylogenetic analysis revealed the presence of two clades. Busseola and Sesamia species were connected in a monophyletic clade with a strong (93%) bootstrap. The second monophyletic clade comprised of a cluster of Pirateolea, Acrapex and Conicofrontia species, and this was also supported with 9 a strong bootstrap (100%). The gene flow study revealed low levels of genetic differentiation between the populations of B. fusca collected from different maize producing areas in South Africa. This low genetic differentiation was consistent with high gene flow. The number of effective migrants between the populations was between 8 and 99 individuals per generation. These results indicate high connectivity between the populations.
- Full Text:
- Date Issued: 2019
Development of part-of-speech tagger for Xhosa
- Authors: Delman, Xolani
- Date: 2016
- Subjects: Computational linguistics -- Methodology Natural language processing (Computer science) Linguistic models
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11872 , vital:39114
- Description: Part-of-Speech (POS) tagging is a process of assigning an appropriate part of speech or lexical category to each word in a given sentence of a particular natural language. Natural languages are languages that human beings use to communicate with one another be it Xhosa, Zulu, English etc. POS tagging plays a huge and important role in natural language processing applications. The main applications of POS tagging include machine translation, parsing, text chunking, spell checkiXhosa (sometimes referred to as isiXhosa) is one of the eleven official languages of South Africa and is spoken by over 8 million South Africans. The language is mainly spoken in the Eastern Cape and Western Cape provinces of the country. It is the second most widely spoken native language in South Africa after Zulu (sometimes called isiZulu). Although the number of speakers might seem to be high, Xhosa is considerably under-resourced. There are very few publications in Xhosa, very few books have been published in the language and also the domains that use the language as a medium of instruction are very limited. However, the language is finding momentum nowadays. An Oxford approved Xhosa dictionary has been developed recently, and Xhosa newspapers that did not exist in the recent past are now published. Text from previously mentioned sources can then be combined to formulate a larger text that can be used to train the tagger. This work aims to develop an effective POS tagger for Xhosa. g and grammar. This thesis presents/describes the work that needed to be done to produce an automatic POS tagger for Xhosa. A tagset consisting of 36 POS tags/labels for the language were used for this purpose. These are listed. A total of 5000 words were manually tagged/labelled for the purpose of training the tagger. Another 3000 words were used for testing the tagger and these were disjoint from the manually tagged training data. The open source Stanford CoreNLP toolkit was used to create the tagger. The toolkit implements a Maximum Entropy machine learning model which was applied in the development of the tagger presented in this thesis. The thesis describes the implementation and testing processes of the model in detail. The results show that the development of the Xhosa POS tagging model was successful. This model managed to obtain a tagging accuracy of 87.71 percent.
- Full Text:
- Date Issued: 2016
- Authors: Delman, Xolani
- Date: 2016
- Subjects: Computational linguistics -- Methodology Natural language processing (Computer science) Linguistic models
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11872 , vital:39114
- Description: Part-of-Speech (POS) tagging is a process of assigning an appropriate part of speech or lexical category to each word in a given sentence of a particular natural language. Natural languages are languages that human beings use to communicate with one another be it Xhosa, Zulu, English etc. POS tagging plays a huge and important role in natural language processing applications. The main applications of POS tagging include machine translation, parsing, text chunking, spell checkiXhosa (sometimes referred to as isiXhosa) is one of the eleven official languages of South Africa and is spoken by over 8 million South Africans. The language is mainly spoken in the Eastern Cape and Western Cape provinces of the country. It is the second most widely spoken native language in South Africa after Zulu (sometimes called isiZulu). Although the number of speakers might seem to be high, Xhosa is considerably under-resourced. There are very few publications in Xhosa, very few books have been published in the language and also the domains that use the language as a medium of instruction are very limited. However, the language is finding momentum nowadays. An Oxford approved Xhosa dictionary has been developed recently, and Xhosa newspapers that did not exist in the recent past are now published. Text from previously mentioned sources can then be combined to formulate a larger text that can be used to train the tagger. This work aims to develop an effective POS tagger for Xhosa. g and grammar. This thesis presents/describes the work that needed to be done to produce an automatic POS tagger for Xhosa. A tagset consisting of 36 POS tags/labels for the language were used for this purpose. These are listed. A total of 5000 words were manually tagged/labelled for the purpose of training the tagger. Another 3000 words were used for testing the tagger and these were disjoint from the manually tagged training data. The open source Stanford CoreNLP toolkit was used to create the tagger. The toolkit implements a Maximum Entropy machine learning model which was applied in the development of the tagger presented in this thesis. The thesis describes the implementation and testing processes of the model in detail. The results show that the development of the Xhosa POS tagging model was successful. This model managed to obtain a tagging accuracy of 87.71 percent.
- Full Text:
- Date Issued: 2016
The effect of muscle type and freezing on the evolution of physico-chemical properties during processing of South African biltong and its final textural properties
- Authors: Ngwendu, Nwabisa
- Date: 2020
- Subjects: Biltong Meat -- Quality -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/12128 , vital:39154
- Description: The study investigated the effect of muscle type and freezing on evaluation of mass transfer during processing physico-chemical of South African biltong and its textural properties. In the first experimental phase of this study, mass transfers, physico-chemical and textural properties (hardness, cohesiveness, springiness, and chewiness) of commercially produced biltong from biceps femoris (BF) and semitendinosus (ST) (n=9) were measured. Biltong was dried at 30oC and 40% relative humidity until it had lost 50% of its initial weight. The initial moisture content, water activity (Aw) of BF muscles (74.3% and 0.992) were significantly lower compared those of ST muscles (75.4% and 0.994%). The fat content of BF (2.3%) muscles was higher (P<0.05) than in ST muscles (1.7%). The salt, weight and water gain for the BF muscle were 2.3%, -2.6% and -7.0% respectively and were significantly higher than those of ST muscles which were 2.1, -0.4 and -4.0, respectively. After drying, the moisture content, Aw, and pH were lower in BF (42.2, 0.886 and 5.29) than those of ST muscles (45.1, 0.911 and 5.42). The salt content was higher (P<0.05) in BF muscle than in ST. Among textural properties, hardness was significantly higher in biltong from the BF (233.0N), while the springiness was significantly lower compared to the ST muscle (178.2N). Therefore, it was concluded that the use of different muscles results in variation of biltong physicochemical characteristics. The second experiment investigated the effect of freezing and muscle type on mass transfers, lipid oxidation, physico-chemical and textural properties of biltong. In this experiment, the iii ST muscles were replaced with semimembranosus (SM) muscles. A total of 12 beef muscles were used, with six BF and six SM muscles frozen in a blast freezer at -40 oC till they reached -20oC; then they were transferred to -20oC for 14 days. The thawing loss for the BF and ST muscles was 1.3 and 2.4% respectively, but there were no significant (P>0.05) differences. The protein and salt content were significantly higher in frozen-thawed (24.3 and 0.13%) muscles than in fresh muscle (20.2 and 0.08%); whereas the fat content and pH were lower (P<0.05) in frozen-thawed (5.36) compared to fresh muscles (5.51). Between muscles, the moisture, salt content, and pH were higher in BF muscles than in SM muscles (73.2, 0.12% and 5.49). Aw was affected by the interaction between freezing and muscle type, with frozenthawed SM having lower Aw (0.990). During salting, salt, weight and water gain did not show any differences (P<0.05). There were no major significant differences after salting. There were lower TBARS and pH in frozen-thawed (1.5mgMDA/kg and 5.15) muscles than in fresh muscles (3.3mgMDA/kg and 5.19) as well as in SM muscles (1.8mgMDA/kg and 5.16) than in BF muscles (3.0mgMDA/kg and 5.19). The moisture was significantly lower in frozen-thawed SM (68.1%) than in fresh SM, BF and frozen-thawed BF (69.3,70.5 and 71.7%) after salting. On the final product, the interaction between muscle type and freezing affected the moisture content, TBARS, chewiness and the springiness of biltong, with the biltong from fresh SM (39.8%) having significantly lower moisture content compared frozenthawed BF and ST muscles as well fresh BF muscles (42.8% in average). The TBARS were higher in biltong from fresh BF muscles (5.1mgMDA/kg) compared to other muscles. Furthermore, the chewiness and springiness were higher (P<0.05) in biltong produced from SM frozen-thawed muscles (327.7N and 1.5). The WBSF was higher in biltong from the BF muscles (108.8N) than in the biltong from SM (80.1) but it was not affected by the freezing effect (P>0.05). Freezing did not show any major differences in biltong. iv The third experiment was conducted to determine the effect of freezing African buffalo carcasses on weight loss during salting, physico-chemical and textural properties of biltong. Five muscles (ST, SM, BF, LTL, and RF) were randomly selected from 30 carcasses (15 frozen-thawed and 15 fresh), cut along the grain, traditionally salted and dried at 26oC till they lost 45-50% of their initial weight. The salting weight loss was higher in frozen-thawed muscles (-1.45%) than in fresh muscles (-0.89%). The freezing treatment affected the physico-chemical properties of the biltong. The biltong produced from frozen-thawed muscles showed significantly higher protein and ash (47.6 and 7.6%) compared to fresh (43.9 and 7.1); whereas the moisture, fat, pH and Aw were lower (43.7, 2.1, 0.870 and 5.30, respectively) compared to those of biltong from fresh muscles (45.5%, 2.9%, 0.890 and 5.38). The moisture, pH and fat content were further affected by muscle type. The interactive effect was observed in salt content, with RF frozen-thawed showing higher salt content (8.2%) compared to all other muscles. The hardness and WBSF were significantly higher (P<0.05) in biltong frozen-thawed (204.1N and 135.0N) than in fresh muscles (146.2N and 113.1N). Moreover, the chewiness and springiness were affected (P<0.05) by muscle type, with RF muscle having higher springiness 0.89 and chewiness 171.1N than all the other muscles. Therefore, it can be concluded that freezing buffalo carcasses significantly influenced the quality characteristics of biltong. The fourth experiment studied the effect of drying methods on physico-chemical properties of traditional biltong produced from African buffalo muscles. The BF and SM muscles were randomly selected from 15 fresh carcasses, cut into strips, salted and divided into two batches per muscle. The first batch of each muscle type was dried in the ambient-air drier at 22oC average and the second batch in the cabinet drier at 26 oC till 45-50% weight loss. No differences (P>0.05) were observed in salting weight loss between the drying method and muscle type. The protein content was significantly higher in SM (46%) muscles compared to v BF (43%) but there was no effect (P>0.05) caused by the drying method. The interactions between the muscle type and drying method affected the fat content, with biltong from airdried BF muscles having significant lower (2.1%) fat content. There were no significant differences in other physico-chemical properties of biltong, with moisture content, salt, ash content, Aw and pH being 45.0%, 5.13%, 44.8%, 7.3%, 2.7%, 0.885 and 5.61 on average, respectively. Overall, the findings of the study show that freezing does have a significant effect on the final quality of biltong. However, it can be concluded that a significant effect on the physico-chemical properties of biltong depends on the changes of mass transfers during salting and drying.
- Full Text:
- Date Issued: 2020
- Authors: Ngwendu, Nwabisa
- Date: 2020
- Subjects: Biltong Meat -- Quality -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/12128 , vital:39154
- Description: The study investigated the effect of muscle type and freezing on evaluation of mass transfer during processing physico-chemical of South African biltong and its textural properties. In the first experimental phase of this study, mass transfers, physico-chemical and textural properties (hardness, cohesiveness, springiness, and chewiness) of commercially produced biltong from biceps femoris (BF) and semitendinosus (ST) (n=9) were measured. Biltong was dried at 30oC and 40% relative humidity until it had lost 50% of its initial weight. The initial moisture content, water activity (Aw) of BF muscles (74.3% and 0.992) were significantly lower compared those of ST muscles (75.4% and 0.994%). The fat content of BF (2.3%) muscles was higher (P<0.05) than in ST muscles (1.7%). The salt, weight and water gain for the BF muscle were 2.3%, -2.6% and -7.0% respectively and were significantly higher than those of ST muscles which were 2.1, -0.4 and -4.0, respectively. After drying, the moisture content, Aw, and pH were lower in BF (42.2, 0.886 and 5.29) than those of ST muscles (45.1, 0.911 and 5.42). The salt content was higher (P<0.05) in BF muscle than in ST. Among textural properties, hardness was significantly higher in biltong from the BF (233.0N), while the springiness was significantly lower compared to the ST muscle (178.2N). Therefore, it was concluded that the use of different muscles results in variation of biltong physicochemical characteristics. The second experiment investigated the effect of freezing and muscle type on mass transfers, lipid oxidation, physico-chemical and textural properties of biltong. In this experiment, the iii ST muscles were replaced with semimembranosus (SM) muscles. A total of 12 beef muscles were used, with six BF and six SM muscles frozen in a blast freezer at -40 oC till they reached -20oC; then they were transferred to -20oC for 14 days. The thawing loss for the BF and ST muscles was 1.3 and 2.4% respectively, but there were no significant (P>0.05) differences. The protein and salt content were significantly higher in frozen-thawed (24.3 and 0.13%) muscles than in fresh muscle (20.2 and 0.08%); whereas the fat content and pH were lower (P<0.05) in frozen-thawed (5.36) compared to fresh muscles (5.51). Between muscles, the moisture, salt content, and pH were higher in BF muscles than in SM muscles (73.2, 0.12% and 5.49). Aw was affected by the interaction between freezing and muscle type, with frozenthawed SM having lower Aw (0.990). During salting, salt, weight and water gain did not show any differences (P<0.05). There were no major significant differences after salting. There were lower TBARS and pH in frozen-thawed (1.5mgMDA/kg and 5.15) muscles than in fresh muscles (3.3mgMDA/kg and 5.19) as well as in SM muscles (1.8mgMDA/kg and 5.16) than in BF muscles (3.0mgMDA/kg and 5.19). The moisture was significantly lower in frozen-thawed SM (68.1%) than in fresh SM, BF and frozen-thawed BF (69.3,70.5 and 71.7%) after salting. On the final product, the interaction between muscle type and freezing affected the moisture content, TBARS, chewiness and the springiness of biltong, with the biltong from fresh SM (39.8%) having significantly lower moisture content compared frozenthawed BF and ST muscles as well fresh BF muscles (42.8% in average). The TBARS were higher in biltong from fresh BF muscles (5.1mgMDA/kg) compared to other muscles. Furthermore, the chewiness and springiness were higher (P<0.05) in biltong produced from SM frozen-thawed muscles (327.7N and 1.5). The WBSF was higher in biltong from the BF muscles (108.8N) than in the biltong from SM (80.1) but it was not affected by the freezing effect (P>0.05). Freezing did not show any major differences in biltong. iv The third experiment was conducted to determine the effect of freezing African buffalo carcasses on weight loss during salting, physico-chemical and textural properties of biltong. Five muscles (ST, SM, BF, LTL, and RF) were randomly selected from 30 carcasses (15 frozen-thawed and 15 fresh), cut along the grain, traditionally salted and dried at 26oC till they lost 45-50% of their initial weight. The salting weight loss was higher in frozen-thawed muscles (-1.45%) than in fresh muscles (-0.89%). The freezing treatment affected the physico-chemical properties of the biltong. The biltong produced from frozen-thawed muscles showed significantly higher protein and ash (47.6 and 7.6%) compared to fresh (43.9 and 7.1); whereas the moisture, fat, pH and Aw were lower (43.7, 2.1, 0.870 and 5.30, respectively) compared to those of biltong from fresh muscles (45.5%, 2.9%, 0.890 and 5.38). The moisture, pH and fat content were further affected by muscle type. The interactive effect was observed in salt content, with RF frozen-thawed showing higher salt content (8.2%) compared to all other muscles. The hardness and WBSF were significantly higher (P<0.05) in biltong frozen-thawed (204.1N and 135.0N) than in fresh muscles (146.2N and 113.1N). Moreover, the chewiness and springiness were affected (P<0.05) by muscle type, with RF muscle having higher springiness 0.89 and chewiness 171.1N than all the other muscles. Therefore, it can be concluded that freezing buffalo carcasses significantly influenced the quality characteristics of biltong. The fourth experiment studied the effect of drying methods on physico-chemical properties of traditional biltong produced from African buffalo muscles. The BF and SM muscles were randomly selected from 15 fresh carcasses, cut into strips, salted and divided into two batches per muscle. The first batch of each muscle type was dried in the ambient-air drier at 22oC average and the second batch in the cabinet drier at 26 oC till 45-50% weight loss. No differences (P>0.05) were observed in salting weight loss between the drying method and muscle type. The protein content was significantly higher in SM (46%) muscles compared to v BF (43%) but there was no effect (P>0.05) caused by the drying method. The interactions between the muscle type and drying method affected the fat content, with biltong from airdried BF muscles having significant lower (2.1%) fat content. There were no significant differences in other physico-chemical properties of biltong, with moisture content, salt, ash content, Aw and pH being 45.0%, 5.13%, 44.8%, 7.3%, 2.7%, 0.885 and 5.61 on average, respectively. Overall, the findings of the study show that freezing does have a significant effect on the final quality of biltong. However, it can be concluded that a significant effect on the physico-chemical properties of biltong depends on the changes of mass transfers during salting and drying.
- Full Text:
- Date Issued: 2020
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
- 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
Socio-economic Impacts of Solar Energy in Rural Communities’ Livelihoods and the Scale/type of Technology Intervention: Case of Ingquza Hill Local Municipality, Eastern Cape Province, South Africa
- Authors: Bongoza, Sibulele
- Date: 2020
- Subjects: Solar energy Renewable energy sources
- Language: English
- Type: Thesis , Masters , MSc (Geography)
- Identifier: http://hdl.handle.net/10353/18610 , vital:42613
- Description: Energy from renewable sources has attracted significant global interest in recent years due to climate change, pollution, extreme environmental impacts and a marked increase in fuel costs for conventional generation methods, which is coal. This has led to major investment in renewable energy sources. Through the lens of sustainable livelihoods framework, the study aims at establishing the socioeconomic impacts brought by the provision of solar energy systems on rural livelihoods at Ingquza Hill Local Municipality in the Eastern Cape Province of South Africa. The study adopts an intensive research design in line with the qualitative approach. Data were collected using questionnaires from the households at Mkhamela village and in-depth interviews with the local councillor and the Chief of Mkhamela village at Ingquza Hill Local Municipality. The use of solar energy systems has been found to improve the rural people’s livelihoods. The rural people’s livelihoods have been transformed in terms of creation of employment opportunities, improved levels of education through powering schools and households as well as improved health conditions.
- Full Text:
- Date Issued: 2020
- Authors: Bongoza, Sibulele
- Date: 2020
- Subjects: Solar energy Renewable energy sources
- Language: English
- Type: Thesis , Masters , MSc (Geography)
- Identifier: http://hdl.handle.net/10353/18610 , vital:42613
- Description: Energy from renewable sources has attracted significant global interest in recent years due to climate change, pollution, extreme environmental impacts and a marked increase in fuel costs for conventional generation methods, which is coal. This has led to major investment in renewable energy sources. Through the lens of sustainable livelihoods framework, the study aims at establishing the socioeconomic impacts brought by the provision of solar energy systems on rural livelihoods at Ingquza Hill Local Municipality in the Eastern Cape Province of South Africa. The study adopts an intensive research design in line with the qualitative approach. Data were collected using questionnaires from the households at Mkhamela village and in-depth interviews with the local councillor and the Chief of Mkhamela village at Ingquza Hill Local Municipality. The use of solar energy systems has been found to improve the rural people’s livelihoods. The rural people’s livelihoods have been transformed in terms of creation of employment opportunities, improved levels of education through powering schools and households as well as improved health conditions.
- Full Text:
- Date Issued: 2020
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
- 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
Production and characterization of a bioflocculant from a consortium of bacteria belonging to the halomonas and micrococcus genera
- Okaiyeto, Kunle (https://orcid.org/0000-0002-7211-714X)
- Authors: Okaiyeto, Kunle (https://orcid.org/0000-0002-7211-714X)
- Date: 2013
- Subjects: Flocculents , Bacteria
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/25822 , vital:64489
- Description: The physicochemical properties of two bioflocculant producing bacteria; Halomonas sp. Okoh and Micrococcus sp. Leo were investigated. The optimum culture conditions for the individual species were determined. All the growth conditions examined for the individual bacteria were similar. Glucose and ammonium sulphate as sole carbon and nitrogen sources respectively resulted in optimum production of bioflocculant. The flocculating activity of the bioflocculants was stimulated when Al3+ was used as the coagulating aid under acidic medium. The information obtained from individual strains was used to produce a bioflocculant from the consortium of the two bacteria. After purification, the bioflocculant yields from 1L fermentation broths were 1.213 g from Halomonas sp. Okoh, 0.738 g from Micrococcus sp. Leo and 3.51 g from the consortium. The chemical analyses of the purified bioflocculants showed that they were glycoproteins. The thermostability property of the bioflocculants was investigated between 50-100oC and the results revealed that they are heat-stable. Fourier transform infrared revealed the presence of hydroxyl, carboxyl and amino groups in the bioflocculant molecules. Scaning electron microscope (SEM) images showed the structure of each bioflocculant(s) and kaolin clay before and after flocculation. From the results obtained, the idea of using the two strains in consortium for bioflocculant production resulted in an improvement in terms of flocculating activity and yield. The bioflocculants appears to have promise as an alternative to chemical flocculants used in various industrial processes such as wastewater treatment and drinking water purification. , Thesis (MA) -- Science and Agriculture, 2013
- Full Text:
- Date Issued: 2013
- Authors: Okaiyeto, Kunle (https://orcid.org/0000-0002-7211-714X)
- Date: 2013
- Subjects: Flocculents , Bacteria
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/25822 , vital:64489
- Description: The physicochemical properties of two bioflocculant producing bacteria; Halomonas sp. Okoh and Micrococcus sp. Leo were investigated. The optimum culture conditions for the individual species were determined. All the growth conditions examined for the individual bacteria were similar. Glucose and ammonium sulphate as sole carbon and nitrogen sources respectively resulted in optimum production of bioflocculant. The flocculating activity of the bioflocculants was stimulated when Al3+ was used as the coagulating aid under acidic medium. The information obtained from individual strains was used to produce a bioflocculant from the consortium of the two bacteria. After purification, the bioflocculant yields from 1L fermentation broths were 1.213 g from Halomonas sp. Okoh, 0.738 g from Micrococcus sp. Leo and 3.51 g from the consortium. The chemical analyses of the purified bioflocculants showed that they were glycoproteins. The thermostability property of the bioflocculants was investigated between 50-100oC and the results revealed that they are heat-stable. Fourier transform infrared revealed the presence of hydroxyl, carboxyl and amino groups in the bioflocculant molecules. Scaning electron microscope (SEM) images showed the structure of each bioflocculant(s) and kaolin clay before and after flocculation. From the results obtained, the idea of using the two strains in consortium for bioflocculant production resulted in an improvement in terms of flocculating activity and yield. The bioflocculants appears to have promise as an alternative to chemical flocculants used in various industrial processes such as wastewater treatment and drinking water purification. , Thesis (MA) -- Science and Agriculture, 2013
- Full Text:
- Date Issued: 2013
Development of an automatic news summarizer for isiXhosa language
- Authors: Ndyalivana, Zukile
- Date: 2017
- Subjects: Text processing (Computer science) Automatic abstracting Computational linguistics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/7875 , vital:30783
- Description: From practice perspective, given the abundance of digital content nowadays, coming up with a technological solution that summarizes written text without losing its message, coherence and cohesion of ideas is highly essential. The technology saves time for readers as well as gives them a chance to focus on the contents that matter most. This is one of the research areas in natural language processing/ information retrieval, which the dissertation tries to contribute to. It tries to contextualize tools and technologies that are developed for other languages to automatically summarize textual Xhosa news articles. Specifically, the dissertation aims at developing a text summarizer for textual Xhosa news articles based on the extraction methods. In doing so, it examines the literature and understand the techniques and technologies used to analyse contents of a written text, transform and synthesize it, the phonology and morphology of the Xhosa language, and finally, designs, implements and test an extraction-based automatic news article for the Xhosa language. Given comprehension and relevance of the literature review, the research design, the methods and tools and technologies used to design, implement and test the pilot system. Two approaches were used to extract relevant sentences, which are, term frequency and sentence position. The Xhosa summarizer is evaluated using a test set. This study has employed both subjective and objective evaluation methods. The results of both methods are satisfactory. Keywords: Xhosa, Automatic Text Summarization, Term Frequency and Sentence Position.
- Full Text:
- Date Issued: 2017
- Authors: Ndyalivana, Zukile
- Date: 2017
- Subjects: Text processing (Computer science) Automatic abstracting Computational linguistics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/7875 , vital:30783
- Description: From practice perspective, given the abundance of digital content nowadays, coming up with a technological solution that summarizes written text without losing its message, coherence and cohesion of ideas is highly essential. The technology saves time for readers as well as gives them a chance to focus on the contents that matter most. This is one of the research areas in natural language processing/ information retrieval, which the dissertation tries to contribute to. It tries to contextualize tools and technologies that are developed for other languages to automatically summarize textual Xhosa news articles. Specifically, the dissertation aims at developing a text summarizer for textual Xhosa news articles based on the extraction methods. In doing so, it examines the literature and understand the techniques and technologies used to analyse contents of a written text, transform and synthesize it, the phonology and morphology of the Xhosa language, and finally, designs, implements and test an extraction-based automatic news article for the Xhosa language. Given comprehension and relevance of the literature review, the research design, the methods and tools and technologies used to design, implement and test the pilot system. Two approaches were used to extract relevant sentences, which are, term frequency and sentence position. The Xhosa summarizer is evaluated using a test set. This study has employed both subjective and objective evaluation methods. The results of both methods are satisfactory. Keywords: Xhosa, Automatic Text Summarization, Term Frequency and Sentence Position.
- Full Text:
- Date Issued: 2017