Phytochemical, antibacterial and pharmacological investigations of Clausena Anisata (Wild). Hook : bone of the medicinal plants used for traditional treatment of "tuberculosis" in Eastern Cape, South Africa
- Authors: Lawal, Ibraheem O
- Date: 2015
- Subjects: Traditional medicine--South Africa--Eastern Cape Tuberculosis--Treatment--South Africa--Eastern Cape Mycobacterial diseases--South Africa--Eastern Cape
- Language: English
- Type: Thesis , Doctoral , Ethnobotany
- Identifier: http://hdl.handle.net/10353/11828 , vital:39110
- Description: Clausena anisata (Willd) Hook, is the only species out of the 15 species of the genus found in the African continent and is regarded as a threatened species in this area of Southern region of Africa. Its distribution spread across Africa to south-east Asia. C. anisata has a wide range of ethno-pharmacological importance. Despite the numerous studies on the pharmacological profile of the plant, there is still dearth of scientific literature on the foliar micro-morphology of this valuable medicinal plant. The morphorlogical structure of the leaves of C. anisata was examined under Light Microscopy (LM), Scanning Electron Microscopy (SEM) and Energy Dispersive x-ray Spectroscopy (EDS) following standard procedures. LM indicates the types of stomata of the leaves (amphistomatic). SEM revealed the presence of the whip like trichomes with its uniqueness to the plants. EDS showed the chemical composition of the foliar appendages which indicated the presence Ca, Mg, S, and Fe. The indication of the elements could probably be helpful in the herbal drug regulation based on the mineral composition and in return reduced herbal drug toxicity.
- Full Text:
- Authors: Lawal, Ibraheem O
- Date: 2015
- Subjects: Traditional medicine--South Africa--Eastern Cape Tuberculosis--Treatment--South Africa--Eastern Cape Mycobacterial diseases--South Africa--Eastern Cape
- Language: English
- Type: Thesis , Doctoral , Ethnobotany
- Identifier: http://hdl.handle.net/10353/11828 , vital:39110
- Description: Clausena anisata (Willd) Hook, is the only species out of the 15 species of the genus found in the African continent and is regarded as a threatened species in this area of Southern region of Africa. Its distribution spread across Africa to south-east Asia. C. anisata has a wide range of ethno-pharmacological importance. Despite the numerous studies on the pharmacological profile of the plant, there is still dearth of scientific literature on the foliar micro-morphology of this valuable medicinal plant. The morphorlogical structure of the leaves of C. anisata was examined under Light Microscopy (LM), Scanning Electron Microscopy (SEM) and Energy Dispersive x-ray Spectroscopy (EDS) following standard procedures. LM indicates the types of stomata of the leaves (amphistomatic). SEM revealed the presence of the whip like trichomes with its uniqueness to the plants. EDS showed the chemical composition of the foliar appendages which indicated the presence Ca, Mg, S, and Fe. The indication of the elements could probably be helpful in the herbal drug regulation based on the mineral composition and in return reduced herbal drug toxicity.
- Full Text:
Prevalence and antibiogram of some swine associated Shiga toxin producing Escherichia coli Serogroups and Salmonella species in Nkonkobe Municipality, Eastern Cape Province, South Africa
- Authors: Iwu, Chinwe Juliana
- Date: 2015
- Subjects: Escherichia coli -- South Africa -- Eastern Cape , Salmonella infections -- South Africa -- Eastern Cape , Water -- Pollution -- Environmental aspects -- South Africa -- Eastern Cape , Escherichia coli infections -- South Africa -- Eastern Cape , Water quality management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11294 , http://hdl.handle.net/10353/d1021273 , Escherichia coli -- South Africa -- Eastern Cape , Salmonella infections -- South Africa -- Eastern Cape , Water -- Pollution -- Environmental aspects -- South Africa -- Eastern Cape , Escherichia coli infections -- South Africa -- Eastern Cape , Water quality management -- South Africa -- Eastern Cape
- Description: Gastrointestinal illnesses have continually become a global public health issue. Exposure to zoonotic food borne pathogens such as Salmonella and diarrhoegenic E. coli either by direct or indirect contact through the consumption of food producing animals is likely an important mode of infection to humans. More so, the use of antibiotics in farm animals similar to those used in humans can select for resistance in bacteria frequently harboured by them. These resistant strains can be passed on to humans through contaminated meat products and water leading to resistant infections with consequences such as prolonged illnesses, treatment failures, and increased morbidity and mortality. In animals, these can lead to reduced productivity. Monitoring the level of resistance among bacteria from animal isolates will help in generating data that could be used to create awareness of their presence in the environment and aid in preventing a potential epidemic in the community. In this study, we investigated the prevalence and antimicrobial resistance profile of Escherichia coli serogroups and Salmonella species in faecal samples collected from pigs in Nkonkobe Municipality in the Eastern Cape Province, South Africa between April – July, 2014. A total of 310 presumptive Shiga toxin producing Escherichia coli (STEC) were confirmed as E. coli spp using polymerase chain reaction (PCR) technique by amplification of the uidA gene, out of which 179 (58%) were confirmed positive. Approximately, serogrougs O157:H7, O145 and O26 made up 24% (n=43), 8% (n=14) and 20% (n=35) of the E. coli population respectively. Only E. coli O26 was positive for stx2 gene in 31% of the isolates harbouring the gene, while the other serogroups were non-pathogenic. Susceptibility of the isolates to 18 antibiotics was carried out in vitro by the standardized agar disc-diffusion method. All the isolates were susceptible to imipenem. Similarly, a relatively high susceptibility was observed in norfloxacin (83-100%), ciprofloxacin (63-100%), gentamycin (77-100%), and chloramphenicol (77-100%). However, all the isolates were resistant to tetracycline and its long acting counterpart oxytetracycline. Resistances observed against other antimicrobials are as follows: ampicillin (84-91%), streptomycin (14-100%), erythromycin (91-100%), ceftazidime (35%). Multiple antimicrobial resistance patterns and indices ranged from 3 to 12 and 0.2 to 0.7 to respectively. Genes encoding resistances to ampicillin (ampC), streptomycin (strA) and tetracycline (tetA) were frequently detected in 50-100%, 22-29% and 40-86% of the resistant isolates respectively. In the other arm of the dissertation, two hundred and fifty eight presumptive isolates of Salmonella were recovered from the faecal samples of pigs. Specific primers targeting serogroups A, B, C1, C2, and D were used to delineate the isolates into different serogroups using PCR. Only serogroup A (n=48) was detected. These isolates were examined for antimicrobial susceptibility by disc diffusion method using 18 antibiotics. The results showed that a large proportion of the isolates were resistant to tetracycline (100%), oxytetracycline (100%), ampicillin (75%), sulphamethoxazole/trimethoprim (75%) and streptomycin (75%). Majority of the isolates exhibited multidrug resistances with the predominant multiple antibiotic resistance (MAR) phenotype being against eleven antibiotics. A high multiple antibiotic resistance (MAR) index in a range of 0.3- 0.6 was observed. The incidence of genes encoding resistance against tetracycline (tetA), streptomycin (stra), and ampicillin (ampC) were 54%, 44% and 61% respectively. These findings reveal that pigs within the Nkonkobe Municipality in the Eastern Cape Province could harbour Shiga toxins and multidrug resistant serogroups of E. coli as well as resistant Salmonella which could be transmitted to humans through the food chain. To ensure public health safety, continuous monitoring and sufficient sanitation in swine industries must be ensured.
- Full Text:
- Authors: Iwu, Chinwe Juliana
- Date: 2015
- Subjects: Escherichia coli -- South Africa -- Eastern Cape , Salmonella infections -- South Africa -- Eastern Cape , Water -- Pollution -- Environmental aspects -- South Africa -- Eastern Cape , Escherichia coli infections -- South Africa -- Eastern Cape , Water quality management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11294 , http://hdl.handle.net/10353/d1021273 , Escherichia coli -- South Africa -- Eastern Cape , Salmonella infections -- South Africa -- Eastern Cape , Water -- Pollution -- Environmental aspects -- South Africa -- Eastern Cape , Escherichia coli infections -- South Africa -- Eastern Cape , Water quality management -- South Africa -- Eastern Cape
- Description: Gastrointestinal illnesses have continually become a global public health issue. Exposure to zoonotic food borne pathogens such as Salmonella and diarrhoegenic E. coli either by direct or indirect contact through the consumption of food producing animals is likely an important mode of infection to humans. More so, the use of antibiotics in farm animals similar to those used in humans can select for resistance in bacteria frequently harboured by them. These resistant strains can be passed on to humans through contaminated meat products and water leading to resistant infections with consequences such as prolonged illnesses, treatment failures, and increased morbidity and mortality. In animals, these can lead to reduced productivity. Monitoring the level of resistance among bacteria from animal isolates will help in generating data that could be used to create awareness of their presence in the environment and aid in preventing a potential epidemic in the community. In this study, we investigated the prevalence and antimicrobial resistance profile of Escherichia coli serogroups and Salmonella species in faecal samples collected from pigs in Nkonkobe Municipality in the Eastern Cape Province, South Africa between April – July, 2014. A total of 310 presumptive Shiga toxin producing Escherichia coli (STEC) were confirmed as E. coli spp using polymerase chain reaction (PCR) technique by amplification of the uidA gene, out of which 179 (58%) were confirmed positive. Approximately, serogrougs O157:H7, O145 and O26 made up 24% (n=43), 8% (n=14) and 20% (n=35) of the E. coli population respectively. Only E. coli O26 was positive for stx2 gene in 31% of the isolates harbouring the gene, while the other serogroups were non-pathogenic. Susceptibility of the isolates to 18 antibiotics was carried out in vitro by the standardized agar disc-diffusion method. All the isolates were susceptible to imipenem. Similarly, a relatively high susceptibility was observed in norfloxacin (83-100%), ciprofloxacin (63-100%), gentamycin (77-100%), and chloramphenicol (77-100%). However, all the isolates were resistant to tetracycline and its long acting counterpart oxytetracycline. Resistances observed against other antimicrobials are as follows: ampicillin (84-91%), streptomycin (14-100%), erythromycin (91-100%), ceftazidime (35%). Multiple antimicrobial resistance patterns and indices ranged from 3 to 12 and 0.2 to 0.7 to respectively. Genes encoding resistances to ampicillin (ampC), streptomycin (strA) and tetracycline (tetA) were frequently detected in 50-100%, 22-29% and 40-86% of the resistant isolates respectively. In the other arm of the dissertation, two hundred and fifty eight presumptive isolates of Salmonella were recovered from the faecal samples of pigs. Specific primers targeting serogroups A, B, C1, C2, and D were used to delineate the isolates into different serogroups using PCR. Only serogroup A (n=48) was detected. These isolates were examined for antimicrobial susceptibility by disc diffusion method using 18 antibiotics. The results showed that a large proportion of the isolates were resistant to tetracycline (100%), oxytetracycline (100%), ampicillin (75%), sulphamethoxazole/trimethoprim (75%) and streptomycin (75%). Majority of the isolates exhibited multidrug resistances with the predominant multiple antibiotic resistance (MAR) phenotype being against eleven antibiotics. A high multiple antibiotic resistance (MAR) index in a range of 0.3- 0.6 was observed. The incidence of genes encoding resistance against tetracycline (tetA), streptomycin (stra), and ampicillin (ampC) were 54%, 44% and 61% respectively. These findings reveal that pigs within the Nkonkobe Municipality in the Eastern Cape Province could harbour Shiga toxins and multidrug resistant serogroups of E. coli as well as resistant Salmonella which could be transmitted to humans through the food chain. To ensure public health safety, continuous monitoring and sufficient sanitation in swine industries must be ensured.
- Full Text:
Primiparous and multiparous cow behaviour of friesland, jersey and cross-bred cows around calving time and during milking
- Authors: Mpisana, Zuko
- Date: 2015
- Subjects: Dairy products--Analysis Jersey cattle Milk yield
- Language: English
- Type: Thesis , Masters , Animal Science
- Identifier: http://hdl.handle.net/10353/16113 , vital:40665
- Description: The objective of the study was to determine effect of behaviour of primiparous and multiparous Friesland, Jersey and Cross-bred cows around calving time and during milking of first lactating cows in a pasture-based dairy system. The trial was conducted at the Fort Hare dairy farm. All pregnant primiparous and multiparous were kept in a maternity paddock. Five observers monitored the cows from the onset of parturition until the calf was fully expelled using digital stop watches. The behavioural responses of the cows during parturition (frequency and duration of lying, standing and walking bouts; calf licking; suckling) and milking (avoidance distance scores (ADS), entrance score, (ES), exit speed (ES), feeding score (FS), and the occurrence of stepping (STP) and kicking (KCK)) were determined on eighty consecutive days. The behavioural attributes were analysed using generalised linear model of procedure of SAS (2003). One hundred and twenty pregnant cows were used in the study, comprising of forty cows per genotype in different parities (A-primiparous, B- 2 to 4, C-5 to 6 and D-7 to 8) and kept in a maternity paddock. Five observers monitored cows from the onset of parturition until the calf was fully expelled. There were differences (P < 0.05) observed on the behavioural patterns around the time of calving. Jersey multiparous cows spent (P < 0.05) significantly most of their time (20.50±3.10) in lying position as compared to the other genotypes. The Jersey genotype also spent most (P < 0.05) of their time (48.00±0.34) in a standing position during calving period. Friesland cows spent (P < 0.05) most of their time (12.00±1.19) exhibiting either stepping or walking attributes as compared to Jersey and Crossbred cows. The Jersey genotype spent significantly (P < 0.05) more time (123.00±10.43) expelling calves compared to the other genotypes. Crossbred cows had the highest avoidance distance (14percent) scores compared to other genotypes and the Friesland cows had the lowest distance scores. The occurrence of kicking was significantly (P < 0.05) higher for the Friesland cows (57.3percent) compared to Jersey (23.2percent) and Crossbred cows (19.6percent). The Friesland cows had the highest (P < 0.05) frequency (36.2percent) feeding score compared to Jersey and Crossbred cows. The Jersey cows had the highest (60.2percent) exit speed compared to other genotypes. The occurrence of stepping was higher for the Friesland cows (53.9percent). The Friesland cows had the highest (P < 0.05) daily milk yield compared to Jersey and Crossbred cows. The present study revealed that behavioural activities of dairy cattle during parturition differed according to genotype and parity and the behavioural response of first lactating cows differ according to genotype during milking.
- Full Text:
- Authors: Mpisana, Zuko
- Date: 2015
- Subjects: Dairy products--Analysis Jersey cattle Milk yield
- Language: English
- Type: Thesis , Masters , Animal Science
- Identifier: http://hdl.handle.net/10353/16113 , vital:40665
- Description: The objective of the study was to determine effect of behaviour of primiparous and multiparous Friesland, Jersey and Cross-bred cows around calving time and during milking of first lactating cows in a pasture-based dairy system. The trial was conducted at the Fort Hare dairy farm. All pregnant primiparous and multiparous were kept in a maternity paddock. Five observers monitored the cows from the onset of parturition until the calf was fully expelled using digital stop watches. The behavioural responses of the cows during parturition (frequency and duration of lying, standing and walking bouts; calf licking; suckling) and milking (avoidance distance scores (ADS), entrance score, (ES), exit speed (ES), feeding score (FS), and the occurrence of stepping (STP) and kicking (KCK)) were determined on eighty consecutive days. The behavioural attributes were analysed using generalised linear model of procedure of SAS (2003). One hundred and twenty pregnant cows were used in the study, comprising of forty cows per genotype in different parities (A-primiparous, B- 2 to 4, C-5 to 6 and D-7 to 8) and kept in a maternity paddock. Five observers monitored cows from the onset of parturition until the calf was fully expelled. There were differences (P < 0.05) observed on the behavioural patterns around the time of calving. Jersey multiparous cows spent (P < 0.05) significantly most of their time (20.50±3.10) in lying position as compared to the other genotypes. The Jersey genotype also spent most (P < 0.05) of their time (48.00±0.34) in a standing position during calving period. Friesland cows spent (P < 0.05) most of their time (12.00±1.19) exhibiting either stepping or walking attributes as compared to Jersey and Crossbred cows. The Jersey genotype spent significantly (P < 0.05) more time (123.00±10.43) expelling calves compared to the other genotypes. Crossbred cows had the highest avoidance distance (14percent) scores compared to other genotypes and the Friesland cows had the lowest distance scores. The occurrence of kicking was significantly (P < 0.05) higher for the Friesland cows (57.3percent) compared to Jersey (23.2percent) and Crossbred cows (19.6percent). The Friesland cows had the highest (P < 0.05) frequency (36.2percent) feeding score compared to Jersey and Crossbred cows. The Jersey cows had the highest (60.2percent) exit speed compared to other genotypes. The occurrence of stepping was higher for the Friesland cows (53.9percent). The Friesland cows had the highest (P < 0.05) daily milk yield compared to Jersey and Crossbred cows. The present study revealed that behavioural activities of dairy cattle during parturition differed according to genotype and parity and the behavioural response of first lactating cows differ according to genotype during milking.
- Full Text:
Reading strategies employed by grade 10 english first additional language teachers to elicit reading culture in the King williams town education district
- Authors: Gcilishe, Tantaswa Brenda
- Date: 2015
- Subjects: Reading-skill strategies Reading (Secondary) -- South Africa -- Eastern Cape English language
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10353/6059 , vital:29487
- Description: This study sought to explore strategies used to elicit a reading culture among secondary schools learners. The importance of reading cannot be over emphasised as it is used as an index to how well an education system is, in the delivering of its mandate of creating a reading nation. In view of this, the South African government has developed a range of legislation and policies that shape reading and literacy in the country. Theoretically, the study is built around the socio-cultural theory which is conceptualised by different reading models. Methodologically, it is premised within the interpretive paradigm based on a case study design. In view of this, the study made use of the Qualitative research method with the principal tools for data collection being; interviews, focus group discussion and, observation. The main findings of the study revealed that using English as the medium of instruction in South Africa is not such a good idea. In this regards, teachers need some form of training to cope with the use of English (a first additional language to both teachers and learners) is a problem in itself. The study recommends that the government needs a) to provide funding to ascertain that resources needed to facilitate reading are available, b) the government should also play the role of monitoring and evaluation to make sure that the policies are kept in place and, c) There is need for in-service training for teachers to make sure that they are living up to expectation. There would be tremendous growth in socio-economic terms with a love for reading being fostered among all members of the school and community.
- Full Text:
- Authors: Gcilishe, Tantaswa Brenda
- Date: 2015
- Subjects: Reading-skill strategies Reading (Secondary) -- South Africa -- Eastern Cape English language
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10353/6059 , vital:29487
- Description: This study sought to explore strategies used to elicit a reading culture among secondary schools learners. The importance of reading cannot be over emphasised as it is used as an index to how well an education system is, in the delivering of its mandate of creating a reading nation. In view of this, the South African government has developed a range of legislation and policies that shape reading and literacy in the country. Theoretically, the study is built around the socio-cultural theory which is conceptualised by different reading models. Methodologically, it is premised within the interpretive paradigm based on a case study design. In view of this, the study made use of the Qualitative research method with the principal tools for data collection being; interviews, focus group discussion and, observation. The main findings of the study revealed that using English as the medium of instruction in South Africa is not such a good idea. In this regards, teachers need some form of training to cope with the use of English (a first additional language to both teachers and learners) is a problem in itself. The study recommends that the government needs a) to provide funding to ascertain that resources needed to facilitate reading are available, b) the government should also play the role of monitoring and evaluation to make sure that the policies are kept in place and, c) There is need for in-service training for teachers to make sure that they are living up to expectation. There would be tremendous growth in socio-economic terms with a love for reading being fostered among all members of the school and community.
- Full Text:
Recycled water usage in peri-urban agriculture : an examination of its socio-economic and environmental benefits in Port Elizabeth
- Authors: Makinana, Anazo
- Date: 2015
- Subjects: Water reuse -- South Africa -- Eastern Cape Water reuse -- Economic aspects -- South Africa Water reuse -- Environmental aspects -- South Africa
- Language: English
- Type: Thesis , Masters , MSoc
- Identifier: http://hdl.handle.net/10353/5719 , vital:29367
- Description: This study examines whether recycled water (specifically grey water) is used in peri-urban agriculture in greater Port Elizabeth. It also investigates the socio-economic as well as environmental benefits of using recycled water in peri-urban agriculture. Community perceptions and narratives about the use of recycled water for farming purposes were also investigated. Study respondents were purposively selected from Motherwell and Uitenhage in Port Elizabeth. A qualitative research methodology and methods were used. This involved using purposive sampling to sample, select and interview 22 respondents and eight key informants. All the respondents were interviewed using in-depth semi-structured interviews. The study found that while many respondents have heard about water recycling, they are however not using recycled grey water for their peri-urban farming activities. Instead, peri-urban farmers continue to use water supplied by the municipality. Recycled water is mostly used for watering sport fields around Port Elizabeth. This continued usage of municipal water (instead of recycled water) is not only costly to the municipality but the individual farmers as well. The respondents were however aware of the benefits of using recycled water. These include economic (money saved from not paying irrigation water bills), environmental (nutrient contents found in recycled water) and socio-economic (conserving fresh available for use in other community purposes). The study recommends that the Nelson Mandela Metro Municipality should do more (through educational and environmental campaigns) to encourage peri-urban farmers to use recycled water in their farming activities.
- Full Text:
- Authors: Makinana, Anazo
- Date: 2015
- Subjects: Water reuse -- South Africa -- Eastern Cape Water reuse -- Economic aspects -- South Africa Water reuse -- Environmental aspects -- South Africa
- Language: English
- Type: Thesis , Masters , MSoc
- Identifier: http://hdl.handle.net/10353/5719 , vital:29367
- Description: This study examines whether recycled water (specifically grey water) is used in peri-urban agriculture in greater Port Elizabeth. It also investigates the socio-economic as well as environmental benefits of using recycled water in peri-urban agriculture. Community perceptions and narratives about the use of recycled water for farming purposes were also investigated. Study respondents were purposively selected from Motherwell and Uitenhage in Port Elizabeth. A qualitative research methodology and methods were used. This involved using purposive sampling to sample, select and interview 22 respondents and eight key informants. All the respondents were interviewed using in-depth semi-structured interviews. The study found that while many respondents have heard about water recycling, they are however not using recycled grey water for their peri-urban farming activities. Instead, peri-urban farmers continue to use water supplied by the municipality. Recycled water is mostly used for watering sport fields around Port Elizabeth. This continued usage of municipal water (instead of recycled water) is not only costly to the municipality but the individual farmers as well. The respondents were however aware of the benefits of using recycled water. These include economic (money saved from not paying irrigation water bills), environmental (nutrient contents found in recycled water) and socio-economic (conserving fresh available for use in other community purposes). The study recommends that the Nelson Mandela Metro Municipality should do more (through educational and environmental campaigns) to encourage peri-urban farmers to use recycled water in their farming activities.
- Full Text:
Regional differentiation of three goatfishes (Parupeneus Spp.) within the Western Indian Ocean
- Springbok–Njokweni, Nosiphiwo
- Authors: Springbok–Njokweni, Nosiphiwo
- Date: 2015
- Subjects: Marine fishes -- South Africa , Mitochondrial DNA -- South Africa , Mullidae -- South Africa , Biogeography -- South Africa
- Language: English
- Type: Thesis , Masters , MSc (Zoology)
- Identifier: vital:11798 , http://hdl.handle.net/10353/d1020262 , Marine fishes -- South Africa , Mitochondrial DNA -- South Africa , Mullidae -- South Africa , Biogeography -- South Africa
- Description: Goatfishes inhabit inshore reefs and corals and are commercially important across their distribution in the Western Indian Ocean (WIO). The biogeography of these species in the WIO has not been explored with regards to their levels of diversity and relationships among regions. The genetic connectivity and differentiation of three goatfishes of the genus Parupeneus (P. barberinus, P. macronemus and P. rubescens) was studied using two mitochondrial genes (ND2 and 16S rRNA) and one nuclear gene (RAG1) using specimens from East and southern Africa, islands around the Mascarene plateau, Oman, Maldives and the Red Sea. Haplotype diversities, networks and AMOVA were used to measure genetic variance among localities and defined regional groups. There were high haplotype (HD > 0.9) and low nucleotide diversities (< 0.006) among all species for all gene regions, suggesting high levels of genetic differentiation among different areas, except for the mtDNA 16S data for P. macronemus and P. rubescens. For all three species, the FST population pairwise values revealed significant differentiation in all datasets for most population pairwise comparisons with the Maldives and genetic connectivity with haplotypes being shared among other localities. The 16S and RAG1, AMOVA for P. barberinus revealed a significant (P < 0.05) strong genetic structure among groups, for example P = 0.00 was estimated in the 16S data for four groups (the Maldives, WIO islands, Kenya and eastern mainland). This study found evidence for regional differentiation within the WIO for these three species supporting the presence of genetic breaks among areas. This differentiation could be either due to the historical isolation among areas or due to geographic and oceanic barriers such as the Mascarene Plateau and the Agulhas Current eddies in the Mozambique Channel. The effects of oceanographic features and physical barriers in the species distribution range and the dispersal potential based on the life history features of the species can have an influence on the genetic structuring of a population. It is also important to note that the length of the pelagic larval phase is just one factor affecting dispersal in marine organisms that can also explain the difference in genetic population structure. Unfortunately there is no specific information on the larval dispersal of these three goatfish. Therefore, studies are needed to be conducted on the specific biology and life history strategies of each Parupeneus species. These results suggest the importance of other factors, such as currents, and larval retention that may cause strong differentiation. These factors should also be considered when observing larval dispersal and its effect on population genetic structure. This study support the hypotheses that physical factors, processes (geographic barriers and oceanographic characteristics) and life history parameters need to be studied to understand the genetic differentiation of these Parupeneus reef fishes.
- Full Text:
- Authors: Springbok–Njokweni, Nosiphiwo
- Date: 2015
- Subjects: Marine fishes -- South Africa , Mitochondrial DNA -- South Africa , Mullidae -- South Africa , Biogeography -- South Africa
- Language: English
- Type: Thesis , Masters , MSc (Zoology)
- Identifier: vital:11798 , http://hdl.handle.net/10353/d1020262 , Marine fishes -- South Africa , Mitochondrial DNA -- South Africa , Mullidae -- South Africa , Biogeography -- South Africa
- Description: Goatfishes inhabit inshore reefs and corals and are commercially important across their distribution in the Western Indian Ocean (WIO). The biogeography of these species in the WIO has not been explored with regards to their levels of diversity and relationships among regions. The genetic connectivity and differentiation of three goatfishes of the genus Parupeneus (P. barberinus, P. macronemus and P. rubescens) was studied using two mitochondrial genes (ND2 and 16S rRNA) and one nuclear gene (RAG1) using specimens from East and southern Africa, islands around the Mascarene plateau, Oman, Maldives and the Red Sea. Haplotype diversities, networks and AMOVA were used to measure genetic variance among localities and defined regional groups. There were high haplotype (HD > 0.9) and low nucleotide diversities (< 0.006) among all species for all gene regions, suggesting high levels of genetic differentiation among different areas, except for the mtDNA 16S data for P. macronemus and P. rubescens. For all three species, the FST population pairwise values revealed significant differentiation in all datasets for most population pairwise comparisons with the Maldives and genetic connectivity with haplotypes being shared among other localities. The 16S and RAG1, AMOVA for P. barberinus revealed a significant (P < 0.05) strong genetic structure among groups, for example P = 0.00 was estimated in the 16S data for four groups (the Maldives, WIO islands, Kenya and eastern mainland). This study found evidence for regional differentiation within the WIO for these three species supporting the presence of genetic breaks among areas. This differentiation could be either due to the historical isolation among areas or due to geographic and oceanic barriers such as the Mascarene Plateau and the Agulhas Current eddies in the Mozambique Channel. The effects of oceanographic features and physical barriers in the species distribution range and the dispersal potential based on the life history features of the species can have an influence on the genetic structuring of a population. It is also important to note that the length of the pelagic larval phase is just one factor affecting dispersal in marine organisms that can also explain the difference in genetic population structure. Unfortunately there is no specific information on the larval dispersal of these three goatfish. Therefore, studies are needed to be conducted on the specific biology and life history strategies of each Parupeneus species. These results suggest the importance of other factors, such as currents, and larval retention that may cause strong differentiation. These factors should also be considered when observing larval dispersal and its effect on population genetic structure. This study support the hypotheses that physical factors, processes (geographic barriers and oceanographic characteristics) and life history parameters need to be studied to understand the genetic differentiation of these Parupeneus reef fishes.
- Full Text:
Retaining learners in primary schools in the East London education district: policy implications
- Authors: Kumanda,Nomaroma
- Date: 2015
- Subjects: Learning ability Dropouts -- South Africa -- Eastern Cape -- Prevention
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10353/6114 , vital:29492
- Description: The purpose of this study is to investigate different ways of retaining learners in teaching and learning practices in grade seven classrooms. The study was conducted in two East London Primary schools. The research took the form of a qualitative interpretive case study focusing on a study sample. The qualitative methods allowed the researcher to gather data in order to describe and interpret teachers‟ knowledge in retaining learners in grade seven classrooms. This critical analysis explored the literature relating to retention of learners if they fail to meet proficiency requirements. The research made use of a qualitative, mixedmethod, and meta-analysis techniques to collect and analyse the data. The study is systematically analysed and categorized according to three themes: retention and social promotion policy effectiveness, causes of dropping out and identification of curriculum and program options. The findings suggested that retaining learners may have some positive effects in the short-term, but that may diminish with time and age. Early detection of academic deficiencies by teachers can possibly prevent negative psychological effects and dropping out due to retention. Student retention in public schools is comparatively poor in traditional education and in some contexts, embarrassingly low. Literature on the subject of student retention in public schools indicates that even when interventions are designed and undertaken to improve student‟s retention, they tend to fall short. The main aim of this dissertation therefore is to better understand and measure learners‟ attitudes and perceptions towards the effectiveness of learning. In view of this, it is hoped that the study can determine how these strategies can be used optimally to improve student retention at lower grades in the East London District in Eastern Cape. The findings at its best indicate what possible method that could be used to improve retention of learners, by enhancing their teaching/ learning and improving the efficacy of Eastern Cape school‟s existing student support system.
- Full Text:
- Authors: Kumanda,Nomaroma
- Date: 2015
- Subjects: Learning ability Dropouts -- South Africa -- Eastern Cape -- Prevention
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10353/6114 , vital:29492
- Description: The purpose of this study is to investigate different ways of retaining learners in teaching and learning practices in grade seven classrooms. The study was conducted in two East London Primary schools. The research took the form of a qualitative interpretive case study focusing on a study sample. The qualitative methods allowed the researcher to gather data in order to describe and interpret teachers‟ knowledge in retaining learners in grade seven classrooms. This critical analysis explored the literature relating to retention of learners if they fail to meet proficiency requirements. The research made use of a qualitative, mixedmethod, and meta-analysis techniques to collect and analyse the data. The study is systematically analysed and categorized according to three themes: retention and social promotion policy effectiveness, causes of dropping out and identification of curriculum and program options. The findings suggested that retaining learners may have some positive effects in the short-term, but that may diminish with time and age. Early detection of academic deficiencies by teachers can possibly prevent negative psychological effects and dropping out due to retention. Student retention in public schools is comparatively poor in traditional education and in some contexts, embarrassingly low. Literature on the subject of student retention in public schools indicates that even when interventions are designed and undertaken to improve student‟s retention, they tend to fall short. The main aim of this dissertation therefore is to better understand and measure learners‟ attitudes and perceptions towards the effectiveness of learning. In view of this, it is hoped that the study can determine how these strategies can be used optimally to improve student retention at lower grades in the East London District in Eastern Cape. The findings at its best indicate what possible method that could be used to improve retention of learners, by enhancing their teaching/ learning and improving the efficacy of Eastern Cape school‟s existing student support system.
- Full Text:
Risk factors associated with developing asthma and tuberculosis: a case study of a hospital, Lagos Nigeria
- Authors: Adeniji, Tolulope Olubunmi
- Date: 2015
- Subjects: Asthma -- Nigeria -- Epidemiology , Diseases -- Risk factors -- Nigeria
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/13216 , vital:39616
- Description: The purpose of the study is to assess risk factors associated with developing asthma and tuberculosis. Methodology: A quantitative study was conducted on 133 randomly selected tuberculosis respondents, 91 of whom were suffering from TB at the time of the study. 120 respondents were also selected randomly for asthma of which 82 were asthmatic. Data were collected by using a self-structured questionnaire. The statistical analysis was done with the statistical package for social sciences (SPSS, version 18) using the descriptive statistics and logistic regression model. Results: Findings from the study show that a large percentage of the participants for both diseases were male, and the carriers of the diseases were also mostly male. Amongst the factors assessed, smoking, a weak immune system and a history of contact with tuberculosis infected persons were factors independently associated with developing tuberculosis. In the case of asthma, family history, smoking and exposure to allergen irritants were the factors independently associated with developing the disease. Conclusion: The findings highlight the need for increasing awareness through information, education and communication to address the risk factors of tuberculosis and asthma in order to decrease the rate of outspread. Recommendations: Factors triggering asthma among humans should be avoided. Since tuberculosis can be contracted through person to person contact, proper sanitation and regular medical attention are advocated for safeguarding personal and public health.
- Full Text:
- Authors: Adeniji, Tolulope Olubunmi
- Date: 2015
- Subjects: Asthma -- Nigeria -- Epidemiology , Diseases -- Risk factors -- Nigeria
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/13216 , vital:39616
- Description: The purpose of the study is to assess risk factors associated with developing asthma and tuberculosis. Methodology: A quantitative study was conducted on 133 randomly selected tuberculosis respondents, 91 of whom were suffering from TB at the time of the study. 120 respondents were also selected randomly for asthma of which 82 were asthmatic. Data were collected by using a self-structured questionnaire. The statistical analysis was done with the statistical package for social sciences (SPSS, version 18) using the descriptive statistics and logistic regression model. Results: Findings from the study show that a large percentage of the participants for both diseases were male, and the carriers of the diseases were also mostly male. Amongst the factors assessed, smoking, a weak immune system and a history of contact with tuberculosis infected persons were factors independently associated with developing tuberculosis. In the case of asthma, family history, smoking and exposure to allergen irritants were the factors independently associated with developing the disease. Conclusion: The findings highlight the need for increasing awareness through information, education and communication to address the risk factors of tuberculosis and asthma in order to decrease the rate of outspread. Recommendations: Factors triggering asthma among humans should be avoided. Since tuberculosis can be contracted through person to person contact, proper sanitation and regular medical attention are advocated for safeguarding personal and public health.
- Full Text:
Risk management : a prerequisite for the implementation of government projects by the Eastern Cape Department of Local Government
- Authors: Sojini, Sandile
- Date: 2015
- Subjects: Risk management -- South Africa -- Eastern Cape Project management -- South Africa -- Eastern Cape Local government -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10353/2755 , vital:28073
- Description: This Research Report that this research was motivated by the fact that despite thetremendous achievements have been realized from the successful implementation ofgovernment programmes and projects related the construction and refurbishment of medical facilities, educational, bridges and road infrastructure facilities. Trends indicate that only iota of evidence implies that the concept of risk management is fully integrated and embraced as part of a culture for ensuring the successful project implementation by the Modern South African public sector organizations. Empirical research revealed that the common types of risks that have been affecting the successful implementation of government projects and programmes include: riots, fraud, corruption, changes in demographic figures, outsourcing risks, and floods and changes in weather. Most of the participants stated that risks associated with riots do not only arise from the riots within the government departments, but also in the external environment. In terms of the internal riots, they revealed that when the employees go on strike or riots on their own or in solidarity with the other trade unions, leading to the process for the implementation of government projects and programmes being affected. Yet, in certain cases, they noted that internal riots or strikes most occur as preceded by rumours that the riots by a particular union will take place and may significantly affect the ongoing process of implementation of government programmes. Besides risks associated with the internal riots by the employees and the communities, the interview findings also indicated that the other forms of risks arise from the strikes and riots by the private enterprises.
- Full Text:
- Authors: Sojini, Sandile
- Date: 2015
- Subjects: Risk management -- South Africa -- Eastern Cape Project management -- South Africa -- Eastern Cape Local government -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10353/2755 , vital:28073
- Description: This Research Report that this research was motivated by the fact that despite thetremendous achievements have been realized from the successful implementation ofgovernment programmes and projects related the construction and refurbishment of medical facilities, educational, bridges and road infrastructure facilities. Trends indicate that only iota of evidence implies that the concept of risk management is fully integrated and embraced as part of a culture for ensuring the successful project implementation by the Modern South African public sector organizations. Empirical research revealed that the common types of risks that have been affecting the successful implementation of government projects and programmes include: riots, fraud, corruption, changes in demographic figures, outsourcing risks, and floods and changes in weather. Most of the participants stated that risks associated with riots do not only arise from the riots within the government departments, but also in the external environment. In terms of the internal riots, they revealed that when the employees go on strike or riots on their own or in solidarity with the other trade unions, leading to the process for the implementation of government projects and programmes being affected. Yet, in certain cases, they noted that internal riots or strikes most occur as preceded by rumours that the riots by a particular union will take place and may significantly affect the ongoing process of implementation of government programmes. Besides risks associated with the internal riots by the employees and the communities, the interview findings also indicated that the other forms of risks arise from the strikes and riots by the private enterprises.
- Full Text:
Risky sexual behaviour in child headed families: A case study of Qora village, Idutywa, Eastern Cape Province
- Authors: Ntutumbo, Nyameka
- Date: 2015
- Subjects: Teenagers -- Sexual behavior -- South Africa -- Eastern Cape Orphans -- Sexual behavior -- South Africa -- Eastern Cape Risk-taking (Psychology)
- Language: English
- Type: Thesis , Masters , Degree
- Identifier: http://hdl.handle.net/10353/5213 , vital:29113
- Description: The study considered the prevalence of risky sexual behaviour in child headed families that usually affects the adolescents in South Africa. This study aimed at exploring the prevalence of risky sexual behaviour in child headed families, determining the causal factors of sexual promiscuous behaviour and effects of promiscuity. The area of investigation was Qora Village which is in a small town called Idutywa, Eastern Cape. This is an area that is characterised by poverty, illiteracy and unemployment. The sample was comprised of 50 participants and the study was conducted in two phases using mixed methods approach. Social exchange theory underpinned the study. Findings highlighted that these child headed adolescents had a role of caregivers and due to poverty they practiced risky sexual behaviour to bridge the economic gap. Furthermore, teenagers living in child headed families were likely to engage in risky sexual behaviour with people who are older than them; others are forced and coerced; while others perceive such act as a better option to bridge the economic gap that existed within their family backgrounds.
- Full Text:
- Authors: Ntutumbo, Nyameka
- Date: 2015
- Subjects: Teenagers -- Sexual behavior -- South Africa -- Eastern Cape Orphans -- Sexual behavior -- South Africa -- Eastern Cape Risk-taking (Psychology)
- Language: English
- Type: Thesis , Masters , Degree
- Identifier: http://hdl.handle.net/10353/5213 , vital:29113
- Description: The study considered the prevalence of risky sexual behaviour in child headed families that usually affects the adolescents in South Africa. This study aimed at exploring the prevalence of risky sexual behaviour in child headed families, determining the causal factors of sexual promiscuous behaviour and effects of promiscuity. The area of investigation was Qora Village which is in a small town called Idutywa, Eastern Cape. This is an area that is characterised by poverty, illiteracy and unemployment. The sample was comprised of 50 participants and the study was conducted in two phases using mixed methods approach. Social exchange theory underpinned the study. Findings highlighted that these child headed adolescents had a role of caregivers and due to poverty they practiced risky sexual behaviour to bridge the economic gap. Furthermore, teenagers living in child headed families were likely to engage in risky sexual behaviour with people who are older than them; others are forced and coerced; while others perceive such act as a better option to bridge the economic gap that existed within their family backgrounds.
- Full Text:
Risky sexual behaviour in child headed families: a case study of Qora Village, Idutywa, Eastern Cape Province
- Authors: Ntutumbo, Nyameka
- Date: 2015
- Subjects: Teenagers -- Sexual behaviour -- South Africa -- Eastern Cape Orphans -- Sexual behavior -- South Africa -- Eastern Cape Risk-taking (Psychology) Child welfare
- Language: English
- Type: Thesis , Masters , M Soc Sci
- Identifier: http://hdl.handle.net/10353/2139 , vital:27614
- Description: The study considered the prevalence of risky sexual behaviour in child headed families that usually affects the adolescents in South Africa. This study aimed at exploring the prevalence of risky sexual behaviour in child headed families, determining the causal factors of sexual promiscuous behaviour and effects of promiscuity. The area of investigation was Qora Village which is in a small town called Idutywa, Eastern Cape. This is an area that is characterised by poverty, illiteracy and unemployment. The sample was comprised of 50 participants and the study was conducted in two phases using mixed methods approach. Social exchange theory underpinned the study. Findings highlighted that these child headed adolescents had a role of caregivers and due to poverty they practiced risky sexual behaviour to bridge the economic gap. Furthermore, teenagers living in child headed families were likely to engage in risky sexual behaviour with people who are older than them; others are forced and coerced; while others perceive such act as a better option to bridge the economic gap that existed within their family backgrounds
- Full Text:
- Authors: Ntutumbo, Nyameka
- Date: 2015
- Subjects: Teenagers -- Sexual behaviour -- South Africa -- Eastern Cape Orphans -- Sexual behavior -- South Africa -- Eastern Cape Risk-taking (Psychology) Child welfare
- Language: English
- Type: Thesis , Masters , M Soc Sci
- Identifier: http://hdl.handle.net/10353/2139 , vital:27614
- Description: The study considered the prevalence of risky sexual behaviour in child headed families that usually affects the adolescents in South Africa. This study aimed at exploring the prevalence of risky sexual behaviour in child headed families, determining the causal factors of sexual promiscuous behaviour and effects of promiscuity. The area of investigation was Qora Village which is in a small town called Idutywa, Eastern Cape. This is an area that is characterised by poverty, illiteracy and unemployment. The sample was comprised of 50 participants and the study was conducted in two phases using mixed methods approach. Social exchange theory underpinned the study. Findings highlighted that these child headed adolescents had a role of caregivers and due to poverty they practiced risky sexual behaviour to bridge the economic gap. Furthermore, teenagers living in child headed families were likely to engage in risky sexual behaviour with people who are older than them; others are forced and coerced; while others perceive such act as a better option to bridge the economic gap that existed within their family backgrounds
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Socio-economic factors influencing apiculture in the Eastern Cape province, South Africa
- Authors: Peter, Luntulwandile
- Date: 2015
- Subjects: Bee culture -- South Africa -- Eastern Cape Honey -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15321 , vital:40362
- Description: The aim of this study was to assess socio-economic factors influencing apiculture in the Eastern Cape Province. In addition, production costs and profitability of beekeeping were determined, and opportunities and challenges to beekeeping were identified. The data was generated from 58 individual interviews using pre-tested structured questionnaires and checklists. This was supplemented by secondary data collected from different published and unpublished sources. Gross margin analysis was employed to examine the income contribution of honey production to household income, and a Linear Regression Model was used to identify the determinants of honey production. Of the twelve variables included in the regression model, only six were found to be statistically significant. These were gender of the beekeeper, access to credit, availability of labour, price of honey, distance to the market, and number of bee colonies owned. On average, each beekeeper owned and operated 35 bee colonies, with an average production of 9 kg of honey per colony per annum; the latter is well beyond a potential production of 35 kg per colony per annum. Beekeeping contributed an average of R12 231.80 per beekeeping household per annum. Except for the honey, no other bee products were produced and marketed. The beekeepers could access the market (retailers and consumers) readily and efficiently; the latter having been determined through calculation and analysing marketing margins. The major constraints to production identified and prioritised by beekeepers in the study area were drought, pests and insects, the shortage of bee forage, and the lack of adequate beekeeping skills. Based on the study results, interventions required to raise the marketable supply of honey produce are recommended.
- Full Text:
- Authors: Peter, Luntulwandile
- Date: 2015
- Subjects: Bee culture -- South Africa -- Eastern Cape Honey -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15321 , vital:40362
- Description: The aim of this study was to assess socio-economic factors influencing apiculture in the Eastern Cape Province. In addition, production costs and profitability of beekeeping were determined, and opportunities and challenges to beekeeping were identified. The data was generated from 58 individual interviews using pre-tested structured questionnaires and checklists. This was supplemented by secondary data collected from different published and unpublished sources. Gross margin analysis was employed to examine the income contribution of honey production to household income, and a Linear Regression Model was used to identify the determinants of honey production. Of the twelve variables included in the regression model, only six were found to be statistically significant. These were gender of the beekeeper, access to credit, availability of labour, price of honey, distance to the market, and number of bee colonies owned. On average, each beekeeper owned and operated 35 bee colonies, with an average production of 9 kg of honey per colony per annum; the latter is well beyond a potential production of 35 kg per colony per annum. Beekeeping contributed an average of R12 231.80 per beekeeping household per annum. Except for the honey, no other bee products were produced and marketed. The beekeepers could access the market (retailers and consumers) readily and efficiently; the latter having been determined through calculation and analysing marketing margins. The major constraints to production identified and prioritised by beekeepers in the study area were drought, pests and insects, the shortage of bee forage, and the lack of adequate beekeeping skills. Based on the study results, interventions required to raise the marketable supply of honey produce are recommended.
- Full Text:
Socio-economic factors influencing the adoption of in-field rainwater harvesting technololgy for enhancing household food security by small holder farmers in the Nkonkobe Municipality, Eastern Cape Province
- Shange, Nomfundo Sinethemba Queen
- Authors: Shange, Nomfundo Sinethemba Queen
- Date: 2015
- Subjects: Farms, Small -- South Africa -- Eastern Cape , Water harvesting -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape , Water resources development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: http://hdl.handle.net/10353/734 , vital:26492 , Farms, Small -- South Africa -- Eastern Cape , Water harvesting -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape , Water resources development -- South Africa -- Eastern Cape
- Description: Infield rainwater harvesting (IRWH) technology has been used in arid and semi-arid parts of the world and promising results have been achieved in terms of increasing yield. The main aim of this study was to identify socio-economic factors determining the adoption of IRWH technology for enhancing household food security by smallholder farmers. The specific objectives were to assess the level of adoption of IRWH technology using descriptive statistics (mean, frequency and percentages). To determine socio-economic factors influencing adoption of IRWH technology, the binary logistic regression mode l was used. To determine whether adopters of IRWH technology are more food secure than non-adopters, the Household Dietary Diversity Score (HDDS) was used as a measure for household food security. For the same objective, to determine socio-economic factors that influence household food security, the binary logistic regression model was also used and adoption of IRWH technology became an independent variable. The study was conducted in Khayalethu, Guquka and Krwakrwa villages in Nkonkobe Municipality in the Eastern Cape Province (EC). The unit of analysis was the individual smallholder farmers practicing agriculture. The availability (accidental) and snowball sampling techniques were used to select 34, 23, 63 respondents from Khayalethu, Guquka and Krwakrwa villages respectively. Since they are non-random, these sampling methods are problematic because of sampling errors. Overall, a sample size of 120 smallholder farmers was targeted for the interviews. Primary and secondary data collected was coded and analysed using statistical package for social sciences (SPSS) version 21. Results were presented using graphs, pie charts and tables (including cross-tables). The descriptive results showed that adoption status of IRWH technology was low in these areas, with 79% not adopting the technology. Food insecurity was high amongst the non-adopters with 86%. On the basis of descriptive analysis it can be concluded that any change in each one of the significant variables can significantly influence the probability of adopting IRWH technology and household food security. The results from the logistic regression model for the incidence of adoption revealed that 6 out of 16 variables were significant, three at 1% (access to extension services, access to information and farmers’ perception towards the IRWH technology); one at 5% (access to market) and two at 10% (access to hired labour and farm income). For the incidence of household food security, out of 17 variables, 6 were significant, three at 1% (adoption of the IRWH technology, access to extension services and farmers’ perception towards the IRWH technology); two at 5% (access to hired labour and household income) and one at 10% (household size). The empirical findings of this study indicate that there are socio-economic factors influencing adoption of IRWH technology and household food security amongst smallholder farmers. This study recommends that the government should provide extension officers and research stations with the capacity, support and physical means to expose smallholder farmers to the IRWH technology through demonstrations and trainings. The government can also introduce agricultural finance institutions in rural areas to assist the rural smallholder farmers to increase their access to credit. Further, it is recommended that smallholder farmers can expand to the communal croplands in order to gain more land size and work as a co-operative or as an association to ease labour constraints.
- Full Text:
- Authors: Shange, Nomfundo Sinethemba Queen
- Date: 2015
- Subjects: Farms, Small -- South Africa -- Eastern Cape , Water harvesting -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape , Water resources development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: http://hdl.handle.net/10353/734 , vital:26492 , Farms, Small -- South Africa -- Eastern Cape , Water harvesting -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape , Water resources development -- South Africa -- Eastern Cape
- Description: Infield rainwater harvesting (IRWH) technology has been used in arid and semi-arid parts of the world and promising results have been achieved in terms of increasing yield. The main aim of this study was to identify socio-economic factors determining the adoption of IRWH technology for enhancing household food security by smallholder farmers. The specific objectives were to assess the level of adoption of IRWH technology using descriptive statistics (mean, frequency and percentages). To determine socio-economic factors influencing adoption of IRWH technology, the binary logistic regression mode l was used. To determine whether adopters of IRWH technology are more food secure than non-adopters, the Household Dietary Diversity Score (HDDS) was used as a measure for household food security. For the same objective, to determine socio-economic factors that influence household food security, the binary logistic regression model was also used and adoption of IRWH technology became an independent variable. The study was conducted in Khayalethu, Guquka and Krwakrwa villages in Nkonkobe Municipality in the Eastern Cape Province (EC). The unit of analysis was the individual smallholder farmers practicing agriculture. The availability (accidental) and snowball sampling techniques were used to select 34, 23, 63 respondents from Khayalethu, Guquka and Krwakrwa villages respectively. Since they are non-random, these sampling methods are problematic because of sampling errors. Overall, a sample size of 120 smallholder farmers was targeted for the interviews. Primary and secondary data collected was coded and analysed using statistical package for social sciences (SPSS) version 21. Results were presented using graphs, pie charts and tables (including cross-tables). The descriptive results showed that adoption status of IRWH technology was low in these areas, with 79% not adopting the technology. Food insecurity was high amongst the non-adopters with 86%. On the basis of descriptive analysis it can be concluded that any change in each one of the significant variables can significantly influence the probability of adopting IRWH technology and household food security. The results from the logistic regression model for the incidence of adoption revealed that 6 out of 16 variables were significant, three at 1% (access to extension services, access to information and farmers’ perception towards the IRWH technology); one at 5% (access to market) and two at 10% (access to hired labour and farm income). For the incidence of household food security, out of 17 variables, 6 were significant, three at 1% (adoption of the IRWH technology, access to extension services and farmers’ perception towards the IRWH technology); two at 5% (access to hired labour and household income) and one at 10% (household size). The empirical findings of this study indicate that there are socio-economic factors influencing adoption of IRWH technology and household food security amongst smallholder farmers. This study recommends that the government should provide extension officers and research stations with the capacity, support and physical means to expose smallholder farmers to the IRWH technology through demonstrations and trainings. The government can also introduce agricultural finance institutions in rural areas to assist the rural smallholder farmers to increase their access to credit. Further, it is recommended that smallholder farmers can expand to the communal croplands in order to gain more land size and work as a co-operative or as an association to ease labour constraints.
- Full Text:
Stratigraphy and sedimentology of the Msikaba formation in KwaZulu Natal South Coast, South Africa
- Authors: Busakwe, Nolukholo Sinovuyo
- Date: 2015
- Subjects: Geology, Stratigraphic Sedimentology -- South Africa -- KwaZulu-Natal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2501 , vital:27877
- Description: The Msikaba Formation is a Late Devonian fluvial and marine succession which outcrops from Hibberdene to Port Edward along the south coast of KwaZulu-Natal Province, South Africa. The Formation is composed of brownish conglomerate at the bottom and white-greyish quartz arenite sequence in the middle and mixed quartz-arenite with feldspathic sandstone in the upper sequence. Previous studies put more emphasis on the correlation of Msikaba Formation with the Natal Group and Cape Supergroup, whereas this study revised the stratigraphy, and also put new insight on the petrography, sedimentary facies, depositional environments and diagenesis of the Formation. The total stratigraphic section attains a thickness of 184 m at Margate area and 186 m at Port Edward area. The stratigraphy of Msikaba Formation is well exposed on the outcrops along the KwaZulu-Natal coastline. The stratigraphy is subdivided into 4 new members along Margate to Shelly beach section; namely Manaba Member, Uvongo Member, Mhlangeni Member and Shelly Beach Member from bottom upward. Twelve sedimentary facies were identified and the sedimentary facies were integrated into 4 facies association: Facies association 1 (Gmm+Sm) represents braided fluvial deposits, Facies association 2 (Gcm+St+Sp+Sl+Shb) represents tidal channel and tidal flat deposit, Facies association 3 (St+Sp+Sr+Sl) is result of shallow marine deposit and Facies association 4 (Sp+Sl+St+Sm) is a mixed marine and fluvial deposit. Each facies association represents a specific stratigraphic unit and were deposited in a specific sedimentary environment. Grain size analysis was conducted on seventeen thin sections and 500 grains were counted from each thin section. The sandstone grain size parameters of mean, sorting, skewness and kurtosis fell under the average of 0.75, 0.78, 0.4 and 1.2φ respectively. The results show that most of the grain size are coarse to medium grained throughout the study areas and sorting of the sandstones are moderate to poorly sorted. The cumulative frequency diagrams and bivariate plots show positive skewness and negative kurtosis, which indicate a high hydrodynamic environment. Modal composition analysis and petrography studies show that detrital components of the Msikaba Formation are dominated by monocrystalline quartz, feldspar (mostly K-feldspar) and lithic fragments of igneous and metamorphic rocks. The sandstones could be classified as quartz arenite, sub-arkosic sandstone and feldspathic litharenite; and the provenance analysis indicates that the sandstones were derived from craton interior, recycled or quartzose recycled sources which may derived from weathering and erosion of igneous and metamorphic rocks. Diagenetic processes of the Msikaba Formation have been passed through early, mid- and late diagenetic stages. Cementation, mineral conversion and compaction affect early diagenetic stage; authigenic minerals, quartz and feldspar overgrowth are presented in mid-diagenetic stage, whereas recrystallization, replacement, deformation and dissolution have been strongly affected late diagenetic stage. Microscopy, XRD and SEM-EDX studies have identified five types of cements including smectite clay, kaolinite, hematite, quartz and feldspar cements. Quartz cement, pore-filling and pore-lining clay are the major type of cements in the Msikaba Formation. Based on the lithology, sedimentary structure and facies variations, the Manaba Member was most probably deposited in a braided fluvial environment, the Uvongo Member was deposited in a tidal channel environment, the Mhlangeni Member was formed in shallow marine storm-influenced environment, whereas the Shelly Beach Member was represented mixed marine and fluvial environment. The sequence stratigraphy of Msikaba Formation constitutes a transgressive sequence from Manaba Member to Uvongo Member, whereas it ended as a regressive sequence from Mhlangeni Member to Shelly beach Member. The Msikaba Formation shows major differences with the Natal Group and Table Mountain Group (Cape Supergroup) in the lithology, stratigraphic sequence, sedimentary structures, facies system, palaeocurrent styles, fossil contents and depositional environments, which demonstrate that they are not the equivalent stratigraphic unit. Therefore, the Msikaba Formation is a separate, younger stratigraphic unit, and cannot correlate with the Natal Group and Table Mountain Group as suggested by previous researchers.
- Full Text:
- Authors: Busakwe, Nolukholo Sinovuyo
- Date: 2015
- Subjects: Geology, Stratigraphic Sedimentology -- South Africa -- KwaZulu-Natal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2501 , vital:27877
- Description: The Msikaba Formation is a Late Devonian fluvial and marine succession which outcrops from Hibberdene to Port Edward along the south coast of KwaZulu-Natal Province, South Africa. The Formation is composed of brownish conglomerate at the bottom and white-greyish quartz arenite sequence in the middle and mixed quartz-arenite with feldspathic sandstone in the upper sequence. Previous studies put more emphasis on the correlation of Msikaba Formation with the Natal Group and Cape Supergroup, whereas this study revised the stratigraphy, and also put new insight on the petrography, sedimentary facies, depositional environments and diagenesis of the Formation. The total stratigraphic section attains a thickness of 184 m at Margate area and 186 m at Port Edward area. The stratigraphy of Msikaba Formation is well exposed on the outcrops along the KwaZulu-Natal coastline. The stratigraphy is subdivided into 4 new members along Margate to Shelly beach section; namely Manaba Member, Uvongo Member, Mhlangeni Member and Shelly Beach Member from bottom upward. Twelve sedimentary facies were identified and the sedimentary facies were integrated into 4 facies association: Facies association 1 (Gmm+Sm) represents braided fluvial deposits, Facies association 2 (Gcm+St+Sp+Sl+Shb) represents tidal channel and tidal flat deposit, Facies association 3 (St+Sp+Sr+Sl) is result of shallow marine deposit and Facies association 4 (Sp+Sl+St+Sm) is a mixed marine and fluvial deposit. Each facies association represents a specific stratigraphic unit and were deposited in a specific sedimentary environment. Grain size analysis was conducted on seventeen thin sections and 500 grains were counted from each thin section. The sandstone grain size parameters of mean, sorting, skewness and kurtosis fell under the average of 0.75, 0.78, 0.4 and 1.2φ respectively. The results show that most of the grain size are coarse to medium grained throughout the study areas and sorting of the sandstones are moderate to poorly sorted. The cumulative frequency diagrams and bivariate plots show positive skewness and negative kurtosis, which indicate a high hydrodynamic environment. Modal composition analysis and petrography studies show that detrital components of the Msikaba Formation are dominated by monocrystalline quartz, feldspar (mostly K-feldspar) and lithic fragments of igneous and metamorphic rocks. The sandstones could be classified as quartz arenite, sub-arkosic sandstone and feldspathic litharenite; and the provenance analysis indicates that the sandstones were derived from craton interior, recycled or quartzose recycled sources which may derived from weathering and erosion of igneous and metamorphic rocks. Diagenetic processes of the Msikaba Formation have been passed through early, mid- and late diagenetic stages. Cementation, mineral conversion and compaction affect early diagenetic stage; authigenic minerals, quartz and feldspar overgrowth are presented in mid-diagenetic stage, whereas recrystallization, replacement, deformation and dissolution have been strongly affected late diagenetic stage. Microscopy, XRD and SEM-EDX studies have identified five types of cements including smectite clay, kaolinite, hematite, quartz and feldspar cements. Quartz cement, pore-filling and pore-lining clay are the major type of cements in the Msikaba Formation. Based on the lithology, sedimentary structure and facies variations, the Manaba Member was most probably deposited in a braided fluvial environment, the Uvongo Member was deposited in a tidal channel environment, the Mhlangeni Member was formed in shallow marine storm-influenced environment, whereas the Shelly Beach Member was represented mixed marine and fluvial environment. The sequence stratigraphy of Msikaba Formation constitutes a transgressive sequence from Manaba Member to Uvongo Member, whereas it ended as a regressive sequence from Mhlangeni Member to Shelly beach Member. The Msikaba Formation shows major differences with the Natal Group and Table Mountain Group (Cape Supergroup) in the lithology, stratigraphic sequence, sedimentary structures, facies system, palaeocurrent styles, fossil contents and depositional environments, which demonstrate that they are not the equivalent stratigraphic unit. Therefore, the Msikaba Formation is a separate, younger stratigraphic unit, and cannot correlate with the Natal Group and Table Mountain Group as suggested by previous researchers.
- Full Text:
Stratigraphy, geochemistry and origin of the manganese ore deposit in Carletonville, North West province of South Africa
- Authors: Pharoe, Benedict Kinshasa
- Date: 2015
- Subjects: Geology, Stratigraphic Geology--South Africa Geochemistry--South Africa
- Language: English
- Type: Thesis , Masters , Geology
- Identifier: http://hdl.handle.net/10353/11641 , vital:39092
- Description: The Carletonville manganese ore-deposit is a Neogene weathered nodule deposit which was developed on the Early Proterozoic Malmani dolomite succession of the Transvaal Supergroup in Carletonville area, North-West Province, South Africa. The deposits were formed from surficial weathering of the underlying Mn-rich dolomites of the Malmani Subgroup and some were formed from weathered Mn-rich Tertiary alluvial-fluvial sediments. These deposits are currently mineralized and hosted in modern Mn-Fe rich soil profiles and occurs at shallow depths, thus the ore is suitable to be mined by open-cast mining. The study dealt with the stratigraphy, petrology, geochemistry, diagenesis and origin of the ore-deposit. The stratigraphic profile of the manganese ore-deposit was subdivided into 8 zones, namely the (A, B, C, D, E, F, G, and H) zones from the surface downwards. On the basis of variation in mineralogical and chemical composition, nodule grain sizes and the zonation colour, the above mentioned zones were further integrated into the Upper (A and B), Middle (C, D and E) and Lower (F, G and H) Zone, with the I zone, the basement zone, representing the underlying Malmani Subgroup stromatolitic dolomite. The Upper Zone represents organic rich, fine grain silty soil which caps the stratigraphic succession in the mine area. Mineralogically, these zones are depleted in manganese and comprises of hematite, kaolinite, micas and quartz grains, with Mn-Fe coated terrigenous clasts concentrated at the lowermost portion of the B-zone along the contact with the underlying zones. The Middle Zone is characteristically medium to fine in grain sizes with reddish colour due to intense weathering of iron minerals to hematite and is depleted in Ca, Na and Mg bearing minerals as a result of dissolution and leaching and is highly concentrated in quartz and caliche fragments. The Lower Zone is coarse grained with dark, reddish-brown colour. The Middle and Lower Zones comprise mainly of Mn and Fe oxides, clays, quartz, limonite, micas and caliche patches. The concentration of manganese is, however, not consistent in these zones from one borehole to the next, it deviates with topography and depth. The overall stratigraphic succession in the mine area can be described as characterizing of basal stromatolitic dolomite of the Malmani Subgroup, overlain by zone of black, powder-like manganiferous wad which is in turn overlain by weathered Mn-rich Tertiary alluvial-fluvial sediments hosting manganiferous nodules. The whole succession is covered by Quaternary sands. The studies undertaken on grain size analysis for the determination of variation in nodule grain sizes with increasing depth along the profile has indicated a perfect variation trend in grain sizes, where the underlying Lower Zone characterizes of coarse grain fraction whilst the overlying Middle Zone is mainly medium to fine grained and the Upper Zone comprise of very fine silt soil. Statistical parameters were used to classify these sediments under Udden-Wentworth grain size classification scheme. Based on these parameters the samples were classified as pebbles and/or gravel on GRADISTAT program and were found to be moderately to poorly sorted, positively skewed with moderate kurtosis and displays a bimodal distribution. Mineralogical analysis with X-Ray Diffraction and petrographic studies indicates that cryptomelane (KMn8 O16) is the major manganese mineral, whereas pyrolusite occurs as a minor manganese mineral in the mine. Other mineral constituents include hematite/goethite, clay minerals, muscovite, quartz, calcite, limonite with minor amount of heavy minerals. The modal composition studies carried out on the terrigenous clasts which are coated on surface by Mn-Fe oxide concentric laminae indicated their nature to be sub-arkoses and quartz arenites. These clasts are found to occur in association with manganiferous nodules in the mine area, with high concentration experienced at the uppermost portion of the profile below the top soil. The provenance studies indicates the source of these terrigenous sediments from cratonic interior to recycle orogen at low plains with a temperate and subhumid climate and on tropical, humid conditions within an area of moderate to low relief. Based on the geochemical studies, different manganese classification schemes were adopted in this study and inferences were made from geochemical data which indicated supergene and hydrogenous source of the Carletonville manganese nodules suggesting precipitation from weathering residues of Malmani dolomite at passive continental margin of tectonic provenance, with temperate and tropical to humid climatic conditions. The diagenetic features were broadly divided into early, mid and uplift diagenetic stage. Early stage includes sediment consolidation which characterized of cementation and neomorphism in carbonate sediments. This period was followed by mid (burial diagenesis) stage which brought about an increase in tightness of grain packing, loss of pore spaces and thinning of beds due to weight of overlying sediments and selective dissolution of framework grains. Mineral dissolution and replacement were common factors during this stage. In the last diagenetic stage, rocks were uplifted, weathered and unroofed by erosion bringing mineral assemblage including newly formed diagenetic minerals into environment of low temperature and pressure, and high oxygen environment.
- Full Text:
- Authors: Pharoe, Benedict Kinshasa
- Date: 2015
- Subjects: Geology, Stratigraphic Geology--South Africa Geochemistry--South Africa
- Language: English
- Type: Thesis , Masters , Geology
- Identifier: http://hdl.handle.net/10353/11641 , vital:39092
- Description: The Carletonville manganese ore-deposit is a Neogene weathered nodule deposit which was developed on the Early Proterozoic Malmani dolomite succession of the Transvaal Supergroup in Carletonville area, North-West Province, South Africa. The deposits were formed from surficial weathering of the underlying Mn-rich dolomites of the Malmani Subgroup and some were formed from weathered Mn-rich Tertiary alluvial-fluvial sediments. These deposits are currently mineralized and hosted in modern Mn-Fe rich soil profiles and occurs at shallow depths, thus the ore is suitable to be mined by open-cast mining. The study dealt with the stratigraphy, petrology, geochemistry, diagenesis and origin of the ore-deposit. The stratigraphic profile of the manganese ore-deposit was subdivided into 8 zones, namely the (A, B, C, D, E, F, G, and H) zones from the surface downwards. On the basis of variation in mineralogical and chemical composition, nodule grain sizes and the zonation colour, the above mentioned zones were further integrated into the Upper (A and B), Middle (C, D and E) and Lower (F, G and H) Zone, with the I zone, the basement zone, representing the underlying Malmani Subgroup stromatolitic dolomite. The Upper Zone represents organic rich, fine grain silty soil which caps the stratigraphic succession in the mine area. Mineralogically, these zones are depleted in manganese and comprises of hematite, kaolinite, micas and quartz grains, with Mn-Fe coated terrigenous clasts concentrated at the lowermost portion of the B-zone along the contact with the underlying zones. The Middle Zone is characteristically medium to fine in grain sizes with reddish colour due to intense weathering of iron minerals to hematite and is depleted in Ca, Na and Mg bearing minerals as a result of dissolution and leaching and is highly concentrated in quartz and caliche fragments. The Lower Zone is coarse grained with dark, reddish-brown colour. The Middle and Lower Zones comprise mainly of Mn and Fe oxides, clays, quartz, limonite, micas and caliche patches. The concentration of manganese is, however, not consistent in these zones from one borehole to the next, it deviates with topography and depth. The overall stratigraphic succession in the mine area can be described as characterizing of basal stromatolitic dolomite of the Malmani Subgroup, overlain by zone of black, powder-like manganiferous wad which is in turn overlain by weathered Mn-rich Tertiary alluvial-fluvial sediments hosting manganiferous nodules. The whole succession is covered by Quaternary sands. The studies undertaken on grain size analysis for the determination of variation in nodule grain sizes with increasing depth along the profile has indicated a perfect variation trend in grain sizes, where the underlying Lower Zone characterizes of coarse grain fraction whilst the overlying Middle Zone is mainly medium to fine grained and the Upper Zone comprise of very fine silt soil. Statistical parameters were used to classify these sediments under Udden-Wentworth grain size classification scheme. Based on these parameters the samples were classified as pebbles and/or gravel on GRADISTAT program and were found to be moderately to poorly sorted, positively skewed with moderate kurtosis and displays a bimodal distribution. Mineralogical analysis with X-Ray Diffraction and petrographic studies indicates that cryptomelane (KMn8 O16) is the major manganese mineral, whereas pyrolusite occurs as a minor manganese mineral in the mine. Other mineral constituents include hematite/goethite, clay minerals, muscovite, quartz, calcite, limonite with minor amount of heavy minerals. The modal composition studies carried out on the terrigenous clasts which are coated on surface by Mn-Fe oxide concentric laminae indicated their nature to be sub-arkoses and quartz arenites. These clasts are found to occur in association with manganiferous nodules in the mine area, with high concentration experienced at the uppermost portion of the profile below the top soil. The provenance studies indicates the source of these terrigenous sediments from cratonic interior to recycle orogen at low plains with a temperate and subhumid climate and on tropical, humid conditions within an area of moderate to low relief. Based on the geochemical studies, different manganese classification schemes were adopted in this study and inferences were made from geochemical data which indicated supergene and hydrogenous source of the Carletonville manganese nodules suggesting precipitation from weathering residues of Malmani dolomite at passive continental margin of tectonic provenance, with temperate and tropical to humid climatic conditions. The diagenetic features were broadly divided into early, mid and uplift diagenetic stage. Early stage includes sediment consolidation which characterized of cementation and neomorphism in carbonate sediments. This period was followed by mid (burial diagenesis) stage which brought about an increase in tightness of grain packing, loss of pore spaces and thinning of beds due to weight of overlying sediments and selective dissolution of framework grains. Mineral dissolution and replacement were common factors during this stage. In the last diagenetic stage, rocks were uplifted, weathered and unroofed by erosion bringing mineral assemblage including newly formed diagenetic minerals into environment of low temperature and pressure, and high oxygen environment.
- Full Text:
Study of the biotransformations and microbiological properties of cymbopogon citratus
- Ajayi, Emmanuel Olusegun https://orcid.org/0000-0002-0838-4948
- Authors: Ajayi, Emmanuel Olusegun https://orcid.org/0000-0002-0838-4948
- Date: 2015
- Subjects: Lemongras , Essences and essential oils
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/19737 , vital:43197
- Description: Variations in the essential oil yield, chemical composition and kinetics of chemical transformation, antibacterial, and antioxidant properties of the Cymbopogon citratus cultivated in Alice, Eastern Cape of South Africa, over a period of 12 months using the solvent-free microwave extraction and the modified forms of conventional hydrodistillation methods have been evaluated. The modified forms involve variation in the pH medium to effect extraction and to obtain the whole leaf extracts of Cymbopogon citratus (lemongrass). The GC-MS analyses of the essential oils revealed the presence of 10, 11, 13, and 9 principal compounds in the microwave, extraction, hydrodistillation (water-distilled), hydrodistillation (aciddistilled and hydrodistillation (base-distilled), respectively with citral being the prominent compound in all the various extraction methods, with the water-distilled method having the highest cumulative citral content under the period specified. Each of the components of the oils varied in quantity and quality of yield at different points of the year. Different extraction methods produce different compounds. Increase in the amount of citral content was observed during the maturation stage of Cymbopogon citratus in all the extraction methods. Quantitative evaluation of antibacterial activity, minimum inhibitory concentration (MIC) values were determined on the oils and extracts of Cymbopogon citratus using agar dilution method. The essential oils obtained using all the methods of extraction showed activity against all the tested bacteria at a concentration of 10 mg mL-1. The minimum inhibitory concentrations for the acid-distilled varied between 1.25 and 5.0 mg mL-1, while those obtained by both water- and base-distilled showed equal activity on the microorganisms with the MIC ranging between 2.5 and 10 mg mL-1. The microwave extraction showed the least activity with the MIC of 10 mg mL-1. This however suggested that the oils obtained through acid-distillation showed the greatest activity than all other methods of extraction. Activity of the various extracts on bacteria showed that the ethanol extract had the highest activity on the tested organisms with MIC ranging between 0.625 and 1.25 mg mL-1. This was closely followed by the acid-extract (1.25 and 5.0 mg mL-1), methanol extract (1.25 and 10 mg mL-1), acetone extract (2.5 and 5.0 mg mL-1), and base extract (5.0 mg mL-1). Both cold water and hot water extracts showed the least activity of MIC, >10 mg mL-1. The antioxidant and free-radical scavenging activity of the obtained oils and extracts were tested by means of 1,1-diphenyl-2-picrylhydrazyl radical (DPPH+) assay, [(2,2ˊ-azino bis-(3-ethylbenzothiazoline-6-sulfonic acid)] (ABTS), nitric oxide and ferric reducing power assays. The oils and extracts showed DPPH radical scavenging ability, but not as high as the standard drugs. The base extract showed a higher reducing power than the standard drug, rutin. There were significant differences in the phytochemicals contents of the various leaf extracts. The acetone extract has the highest flavonol, proanthocyanidin, and alkaloid contents. The ethanol extract showed the highest amount of phenolic content with the acid extract, having the least. Thin layer chromatography (TLC) and column chromatography was employed to obtain different fractions of extracts using four eluent solvent systems of varying polarities: toluene, petroleum ether, hexane and ethyl acetate and sprayed with anisaldehyde. A single, visible spot of B-fraction was developed, collected and analyzed as 1-methyl-2,4,5- trinitroimidazole with renown valuable properties. , Thesis (PhD) -- Faculty of Science and Agriculture, 2015
- Full Text:
- Authors: Ajayi, Emmanuel Olusegun https://orcid.org/0000-0002-0838-4948
- Date: 2015
- Subjects: Lemongras , Essences and essential oils
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/19737 , vital:43197
- Description: Variations in the essential oil yield, chemical composition and kinetics of chemical transformation, antibacterial, and antioxidant properties of the Cymbopogon citratus cultivated in Alice, Eastern Cape of South Africa, over a period of 12 months using the solvent-free microwave extraction and the modified forms of conventional hydrodistillation methods have been evaluated. The modified forms involve variation in the pH medium to effect extraction and to obtain the whole leaf extracts of Cymbopogon citratus (lemongrass). The GC-MS analyses of the essential oils revealed the presence of 10, 11, 13, and 9 principal compounds in the microwave, extraction, hydrodistillation (water-distilled), hydrodistillation (aciddistilled and hydrodistillation (base-distilled), respectively with citral being the prominent compound in all the various extraction methods, with the water-distilled method having the highest cumulative citral content under the period specified. Each of the components of the oils varied in quantity and quality of yield at different points of the year. Different extraction methods produce different compounds. Increase in the amount of citral content was observed during the maturation stage of Cymbopogon citratus in all the extraction methods. Quantitative evaluation of antibacterial activity, minimum inhibitory concentration (MIC) values were determined on the oils and extracts of Cymbopogon citratus using agar dilution method. The essential oils obtained using all the methods of extraction showed activity against all the tested bacteria at a concentration of 10 mg mL-1. The minimum inhibitory concentrations for the acid-distilled varied between 1.25 and 5.0 mg mL-1, while those obtained by both water- and base-distilled showed equal activity on the microorganisms with the MIC ranging between 2.5 and 10 mg mL-1. The microwave extraction showed the least activity with the MIC of 10 mg mL-1. This however suggested that the oils obtained through acid-distillation showed the greatest activity than all other methods of extraction. Activity of the various extracts on bacteria showed that the ethanol extract had the highest activity on the tested organisms with MIC ranging between 0.625 and 1.25 mg mL-1. This was closely followed by the acid-extract (1.25 and 5.0 mg mL-1), methanol extract (1.25 and 10 mg mL-1), acetone extract (2.5 and 5.0 mg mL-1), and base extract (5.0 mg mL-1). Both cold water and hot water extracts showed the least activity of MIC, >10 mg mL-1. The antioxidant and free-radical scavenging activity of the obtained oils and extracts were tested by means of 1,1-diphenyl-2-picrylhydrazyl radical (DPPH+) assay, [(2,2ˊ-azino bis-(3-ethylbenzothiazoline-6-sulfonic acid)] (ABTS), nitric oxide and ferric reducing power assays. The oils and extracts showed DPPH radical scavenging ability, but not as high as the standard drugs. The base extract showed a higher reducing power than the standard drug, rutin. There were significant differences in the phytochemicals contents of the various leaf extracts. The acetone extract has the highest flavonol, proanthocyanidin, and alkaloid contents. The ethanol extract showed the highest amount of phenolic content with the acid extract, having the least. Thin layer chromatography (TLC) and column chromatography was employed to obtain different fractions of extracts using four eluent solvent systems of varying polarities: toluene, petroleum ether, hexane and ethyl acetate and sprayed with anisaldehyde. A single, visible spot of B-fraction was developed, collected and analyzed as 1-methyl-2,4,5- trinitroimidazole with renown valuable properties. , Thesis (PhD) -- Faculty of Science and Agriculture, 2015
- Full Text:
Supporting the implementation of alternatives to corporal punishment in the Eastern Cape secondary schools : towards a framework for school management teams and teachers
- Authors: Kalipa, Velelo Clifton
- Date: 2015
- Subjects: School discipline -- South Africa -- Eastern Cape Corporal punishment of children -- South Africa -- Eastern Cape Rewards and punishments in education
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/5664 , vital:29359
- Description: Alternative to corporal punishment in schools is a worldwide practice. Most countries have banned the use of corporal punishment in schools and have promulgated laws and adopted policies aiming to enforce the practice of alternative to corporal punishment. South Africa is one of the countries that have introduced policy on alternatives to corporal punishment. However, this policy does not provide details on how School Management Teams (SMTs) and teachers should support the implementation of alternatives to corporal punishment; as a result, schools end up having different approaches in as far as implementing alternatives to corporal punishment is concerned. There is also a serious problem of indiscipline in schools and this has since attracted growing attention of researchers in South Africa and the whole world. There are serious offences by learners in schools which range from serious criminal ones such as drug abuse, assaults, theft, murders and rapes to less serious ones such as truancy, incomplete projects, absenteeism and lateness, dodging and bunking of classes in schools. This study therefore sought to investigate how SMT and teachers support the implementation of alternatives to corporal punishment in schools. This was a multi case study of four secondary schools in the King Williams Town Education District which was conducted through qualitative research approach. Interviews and documentary analysis were used to collect data and a total of 16 participants (four principals, four SMT members and eight teachers) were selected. From the data, it emerged that some teachers were fixed in using corporal punishment to discipline learners in schools. The data also showed that the alternatives to corporal punishment (ATCP) policies were inconsistently applied as schools had different approaches in as far as how ATCP is implemented and that some schools had no ATCP policies at all. It also emerged from the data that school leadership was a problem in as far as supporting the implementation of ATCP in schools as in some schools the issues of disciplining learners was centralised in the principal’s office. It also became clear that the majority of participants did not understand the national policy on ATCP. There were no indications of parental involvement in the implementation of ATCP in schools. It can be concluded that the channels of communication among principals, SMTs, teachers with regards to the implementation of ATCP was problematic as there were no clear roles as to how each of these officials should implement ATCP. Some teachers still perceived the ATCP as unsuitable for maintaining discipline in rural schools and their discipline strategies were still characterized by punitive measures which border on corporal punishment. School discipline was not seen as a societal matter where other relevant stakeholders could play a pivotal role in learner discipline. This had a negative impact on the school discipline. Learners had no responsibility on maintenance of positive school atmosphere as they were not in any way part taking in the maintenance of discipline in schools. This study therefore recommends a comprehensive framework for the implementation of ATCP that will give details on the roles of SMTs and teachers in the implementation of ATCP in schools. It is recommended that this framework be inclusive of parents and other community stakeholders who would give different perspectives on the implementation of ATCP in schools as education is a societal matter. It is also recommended that more research be conducted that will deal with urban schools and on the involvement of parents and other stakeholders in the implementation of ATCP.
- Full Text:
- Authors: Kalipa, Velelo Clifton
- Date: 2015
- Subjects: School discipline -- South Africa -- Eastern Cape Corporal punishment of children -- South Africa -- Eastern Cape Rewards and punishments in education
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/5664 , vital:29359
- Description: Alternative to corporal punishment in schools is a worldwide practice. Most countries have banned the use of corporal punishment in schools and have promulgated laws and adopted policies aiming to enforce the practice of alternative to corporal punishment. South Africa is one of the countries that have introduced policy on alternatives to corporal punishment. However, this policy does not provide details on how School Management Teams (SMTs) and teachers should support the implementation of alternatives to corporal punishment; as a result, schools end up having different approaches in as far as implementing alternatives to corporal punishment is concerned. There is also a serious problem of indiscipline in schools and this has since attracted growing attention of researchers in South Africa and the whole world. There are serious offences by learners in schools which range from serious criminal ones such as drug abuse, assaults, theft, murders and rapes to less serious ones such as truancy, incomplete projects, absenteeism and lateness, dodging and bunking of classes in schools. This study therefore sought to investigate how SMT and teachers support the implementation of alternatives to corporal punishment in schools. This was a multi case study of four secondary schools in the King Williams Town Education District which was conducted through qualitative research approach. Interviews and documentary analysis were used to collect data and a total of 16 participants (four principals, four SMT members and eight teachers) were selected. From the data, it emerged that some teachers were fixed in using corporal punishment to discipline learners in schools. The data also showed that the alternatives to corporal punishment (ATCP) policies were inconsistently applied as schools had different approaches in as far as how ATCP is implemented and that some schools had no ATCP policies at all. It also emerged from the data that school leadership was a problem in as far as supporting the implementation of ATCP in schools as in some schools the issues of disciplining learners was centralised in the principal’s office. It also became clear that the majority of participants did not understand the national policy on ATCP. There were no indications of parental involvement in the implementation of ATCP in schools. It can be concluded that the channels of communication among principals, SMTs, teachers with regards to the implementation of ATCP was problematic as there were no clear roles as to how each of these officials should implement ATCP. Some teachers still perceived the ATCP as unsuitable for maintaining discipline in rural schools and their discipline strategies were still characterized by punitive measures which border on corporal punishment. School discipline was not seen as a societal matter where other relevant stakeholders could play a pivotal role in learner discipline. This had a negative impact on the school discipline. Learners had no responsibility on maintenance of positive school atmosphere as they were not in any way part taking in the maintenance of discipline in schools. This study therefore recommends a comprehensive framework for the implementation of ATCP that will give details on the roles of SMTs and teachers in the implementation of ATCP in schools. It is recommended that this framework be inclusive of parents and other community stakeholders who would give different perspectives on the implementation of ATCP in schools as education is a societal matter. It is also recommended that more research be conducted that will deal with urban schools and on the involvement of parents and other stakeholders in the implementation of ATCP.
- Full Text:
Synthesis and characterization of Ru(II) phenyl-3-indenylidene olefin metathesis type complexes
- Authors: Yalezo, Ntsikelelo
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11351 , http://hdl.handle.net/10353/d1021128
- Description: In this study, a series of Ru(II) phenyl-3-indenylidene complexes with general formula of [RuCl2(NHC)(Ind)(L)] (where L= triphenylphosphine, pyridine and NHC = five different types of N-heterocyclic carbene ligands), have been synthesized and characterized using FT-IR, UV-Vis, elementally analysis and melting/decomposition point. The N,N’-diarylimidazolinium chlorides have been used as N-heterocyclic carbene precursors and were synthesized from their corresponding N,N’-diarylformamidines and further characterized using 1H-NMR, 13C-NMR, FTIR and melting point determination. The infrared spectra of the N,N’-diarylimidazolinium chlorides show a quaternary nature (R2N=C+) with broad vibration band in region 3300-3400 cm-1. The disappearance of this vibration band in the infrared spectra of the ruthenium(II) complexes was used to confirm the coordination of the ligand to the ruthenium ions. The percentage analysis of carbon, hydrogen and nitrogen obtained corresponded with the calculated percentages of these atoms in the complexes with the slight difference of less than 1%. The electronic spectra of the complexes show three distinct absorption bands. The two bands are due to intraligand charge transfers transition assigned to π→π*, n→π* and third band is due to d-d transition, signifying the presence of the metal ion. The synthesized Ru(II) complexes did not show any of melting, however a change in colour was observed signifying the decomposition of the complexes.
- Full Text:
- Authors: Yalezo, Ntsikelelo
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11351 , http://hdl.handle.net/10353/d1021128
- Description: In this study, a series of Ru(II) phenyl-3-indenylidene complexes with general formula of [RuCl2(NHC)(Ind)(L)] (where L= triphenylphosphine, pyridine and NHC = five different types of N-heterocyclic carbene ligands), have been synthesized and characterized using FT-IR, UV-Vis, elementally analysis and melting/decomposition point. The N,N’-diarylimidazolinium chlorides have been used as N-heterocyclic carbene precursors and were synthesized from their corresponding N,N’-diarylformamidines and further characterized using 1H-NMR, 13C-NMR, FTIR and melting point determination. The infrared spectra of the N,N’-diarylimidazolinium chlorides show a quaternary nature (R2N=C+) with broad vibration band in region 3300-3400 cm-1. The disappearance of this vibration band in the infrared spectra of the ruthenium(II) complexes was used to confirm the coordination of the ligand to the ruthenium ions. The percentage analysis of carbon, hydrogen and nitrogen obtained corresponded with the calculated percentages of these atoms in the complexes with the slight difference of less than 1%. The electronic spectra of the complexes show three distinct absorption bands. The two bands are due to intraligand charge transfers transition assigned to π→π*, n→π* and third band is due to d-d transition, signifying the presence of the metal ion. The synthesized Ru(II) complexes did not show any of melting, however a change in colour was observed signifying the decomposition of the complexes.
- Full Text:
Synthesis, characterisation and evaluation of functionalized Lignocelluloses-clay nanocomposites for organic pollutant removal from water
- Authors: Mafukidze, Donovan M
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11356 , http://hdl.handle.net/10353/d1021296
- Description: PMPSgLig-NaMMT nanocomposites were prepared from methacryloxypropyltrimethoxysilane (MPS), lignocellulose and montmorillonite clay. The potential enhancement of organic pollutant adsorption capabilities of PMPSgLig-NaMMT nanocomposite from water through functionalization was investigated. PMPSgLig-NaMMT was functionalized by esterification and etherification using different methods so as to increase the surface hydrophobicity of the material and hence improve its compatibility with the target pollutants. Specific chemical routes specially tailored for PMPSgLig-NaMMT were established for functionalization mostly based on the common esterification (Fischer esterification) and etherification (Williamson‟s etherification) reactions. In the functionalization methods, factors such as pH environment, nanocomposite composition, nature of functionalization moiety, and use of or absence of solvents and their variations were studied. FT-IR, XRD, SEM and TGA were used to characterize the synthesized and functionalized nanoadsorbents. The techniques showed successful functionalization via esterification and etherification methods albeit to different extents, with clear retention of the material‟s original structure though there were signs of degradation with some methods. Characterization was supported by adsorption studies to validate implications and draw conclusions. The use of 1,10-phenathroline as a model organic pollutant in water in the adsorption studies showed that adsorbents conformed to monolayer adsorption following pseudo-second order kinetics for adsorption of organic pollutants accurately represented. Most importantly the studies revealed the significant impact of the nanocomposite composition on the overall absorbent performance. Adsorption studies also showed that functionalization via esterification methods gave rise to better adsorbents.
- Full Text:
- Authors: Mafukidze, Donovan M
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11356 , http://hdl.handle.net/10353/d1021296
- Description: PMPSgLig-NaMMT nanocomposites were prepared from methacryloxypropyltrimethoxysilane (MPS), lignocellulose and montmorillonite clay. The potential enhancement of organic pollutant adsorption capabilities of PMPSgLig-NaMMT nanocomposite from water through functionalization was investigated. PMPSgLig-NaMMT was functionalized by esterification and etherification using different methods so as to increase the surface hydrophobicity of the material and hence improve its compatibility with the target pollutants. Specific chemical routes specially tailored for PMPSgLig-NaMMT were established for functionalization mostly based on the common esterification (Fischer esterification) and etherification (Williamson‟s etherification) reactions. In the functionalization methods, factors such as pH environment, nanocomposite composition, nature of functionalization moiety, and use of or absence of solvents and their variations were studied. FT-IR, XRD, SEM and TGA were used to characterize the synthesized and functionalized nanoadsorbents. The techniques showed successful functionalization via esterification and etherification methods albeit to different extents, with clear retention of the material‟s original structure though there were signs of degradation with some methods. Characterization was supported by adsorption studies to validate implications and draw conclusions. The use of 1,10-phenathroline as a model organic pollutant in water in the adsorption studies showed that adsorbents conformed to monolayer adsorption following pseudo-second order kinetics for adsorption of organic pollutants accurately represented. Most importantly the studies revealed the significant impact of the nanocomposite composition on the overall absorbent performance. Adsorption studies also showed that functionalization via esterification methods gave rise to better adsorbents.
- Full Text:
Synthesis, characterization & application of visible light responsive nitrogen doped Tio2 and copolymer-grafted asymmetric membranes with ozonolysis for water treatment
- Authors: Mungondori, Henry H
- Date: 2015
- Language: English
- Type: Thesis , Doctoral , PhD (Chemistry)
- Identifier: vital:11350 , http://hdl.handle.net/10353/d1020257
- Description: The use of titanium dioxide for the photo-catalytic removal of organic, inorganic, and microbial pollutants from natural water and wastewater has been considered a very promising technique. The aim of this study was to prepare nitrogen doped titanium dioxide, immobilize it on asymmetric polymeric membranes of poly (methacrylic acid) grafted onto poly (vinylidene difluoride) (PVDF) blended with poly (acrylonitrile) (PAN), and evaluate the photo-catalytic, antimicrobial, and antifouling properties of the membranes. Nitrogen doped titanium dioxide (N-TiO2) nano-particles were prepared by a low temperature sol gel synthesis technique. The modification of TiO2 with nitrogen allows photo-sensitization of the photo-catalyst towards visible light utilization. The N-TiO2 nano-particles were characterized by fourier transform infrared spectroscopy (FT-IR), scanning x-ray photoelectron spectroscopy (SXPS), X-ray diffraction analysis (XRD), diffuse reflectance spectroscopy (DRS), Brunauer Emmett Teller (BET) surface area analysis, and transmission electron microscopy (TEM). The characterizations revealed the presence of the expected functional groups and confirmed successful doping and that the product was visible light responsive. Novel poly (methacrylic acid) grafted onto poly (vinylidene difluoride)/ poly (acrylonitrile) (PMAA-g-PVDF/ PAN) asymmetric membranes were prepared by the dry-wet phase inversion technique. The poly (methacrylic acid) (PMAA) side chains where grafted onto an activated PVDF backbone by reversible addition fragmentation chain transfer (RAFT) polymerization. The photo-catalytic membranes were generated by blending N-TiO2 with the polymer solution before casting the membranes. The membranes were characterized by FT-IR, nuclear magnetic resonance spectroscopy (NMR), scanning electron microscopy (SEM), and thermo-gravimetric analysis (TGA). FT-IR and NMR analyses confirmed successful grafting of MAA chains onto PVDF while SEM confirmed the successful preparation of membranes with asymmetric structure. The efficacy of the photo-catalytic asymmetric membranes was evaluated on the removal of herbicides from synthetic water. Bentazon was easily degraded while atrazine and paraquat were recalcitrant and proved difficult to degrade. The best results were observed with 3 % N-TiO2-PMAA-g-PVDF/ PAN asymmetric membranes on the photo-degradation of bentazon, atrazine and paraquat in water. Significant enhancement in the photo-degradation of the three herbicides was observed when photo-catalytic degradation was coupled with ozonation. Liquid chromatography-mass spectrometry (LC-MS) analysis confirmed the presence of a degradation by-product during the photo-catalytic degradation of bentazon. The photo-catalytic membranes were also evaluated on the photo-catalytic reduction of heavy metals Pb2+ and Fe3+ in water, and the best results were obtained using 1 % N-TiO2-PMAA-g-PVDF/ PAN and 1 % N-TiO2-PAN asymmetric membranes. All prepared photo-catalytic membranes where capable of completely inactivating E. coli ATCC 8739 within 120 minutes of exposure and inactivation rate increased with increasing N-TiO2 photo-catalyst loading. However, there was an indication from the results obtained that N-TiO2 supported on PMAA-g-PVDF/ PAN showed a higher inactivation rate of E. coli ATCC 8739 compared to N-TiO2-PAN and N-TiO2-PVDF membranes. The 1 % N-TiO2-PMAA-g-PVDF/ PAN membranes gave the highest pure water flux (421.83 L/m2h). This increase (PVDF = 30.50 L/m2h, PAN = 73.85 L/m2h) in pure water flux is owedb to PMAA grafting as well as addition of N-TiO2. These modifications resulted in an increased membrane surface hydrophilicity, which promoted permeation of pure water through the membrane structure. A high bovine serum albumin (BSA) rejection (76.5 %) was noted and can be attributed to steric hindrance brought about by PMAA side chains which prevented the bulky BSA molecules from attaching to the membrane surface for PMAA-g-PVDF/ PAN membranes. However, the supporting porous sub-layer of an asymmetric membrane seemed to play a very important role in the overall permeability of a membrane. PVDF membranes are highly hydrophobic hence they gave a very low pure water flux.
- Full Text:
- Authors: Mungondori, Henry H
- Date: 2015
- Language: English
- Type: Thesis , Doctoral , PhD (Chemistry)
- Identifier: vital:11350 , http://hdl.handle.net/10353/d1020257
- Description: The use of titanium dioxide for the photo-catalytic removal of organic, inorganic, and microbial pollutants from natural water and wastewater has been considered a very promising technique. The aim of this study was to prepare nitrogen doped titanium dioxide, immobilize it on asymmetric polymeric membranes of poly (methacrylic acid) grafted onto poly (vinylidene difluoride) (PVDF) blended with poly (acrylonitrile) (PAN), and evaluate the photo-catalytic, antimicrobial, and antifouling properties of the membranes. Nitrogen doped titanium dioxide (N-TiO2) nano-particles were prepared by a low temperature sol gel synthesis technique. The modification of TiO2 with nitrogen allows photo-sensitization of the photo-catalyst towards visible light utilization. The N-TiO2 nano-particles were characterized by fourier transform infrared spectroscopy (FT-IR), scanning x-ray photoelectron spectroscopy (SXPS), X-ray diffraction analysis (XRD), diffuse reflectance spectroscopy (DRS), Brunauer Emmett Teller (BET) surface area analysis, and transmission electron microscopy (TEM). The characterizations revealed the presence of the expected functional groups and confirmed successful doping and that the product was visible light responsive. Novel poly (methacrylic acid) grafted onto poly (vinylidene difluoride)/ poly (acrylonitrile) (PMAA-g-PVDF/ PAN) asymmetric membranes were prepared by the dry-wet phase inversion technique. The poly (methacrylic acid) (PMAA) side chains where grafted onto an activated PVDF backbone by reversible addition fragmentation chain transfer (RAFT) polymerization. The photo-catalytic membranes were generated by blending N-TiO2 with the polymer solution before casting the membranes. The membranes were characterized by FT-IR, nuclear magnetic resonance spectroscopy (NMR), scanning electron microscopy (SEM), and thermo-gravimetric analysis (TGA). FT-IR and NMR analyses confirmed successful grafting of MAA chains onto PVDF while SEM confirmed the successful preparation of membranes with asymmetric structure. The efficacy of the photo-catalytic asymmetric membranes was evaluated on the removal of herbicides from synthetic water. Bentazon was easily degraded while atrazine and paraquat were recalcitrant and proved difficult to degrade. The best results were observed with 3 % N-TiO2-PMAA-g-PVDF/ PAN asymmetric membranes on the photo-degradation of bentazon, atrazine and paraquat in water. Significant enhancement in the photo-degradation of the three herbicides was observed when photo-catalytic degradation was coupled with ozonation. Liquid chromatography-mass spectrometry (LC-MS) analysis confirmed the presence of a degradation by-product during the photo-catalytic degradation of bentazon. The photo-catalytic membranes were also evaluated on the photo-catalytic reduction of heavy metals Pb2+ and Fe3+ in water, and the best results were obtained using 1 % N-TiO2-PMAA-g-PVDF/ PAN and 1 % N-TiO2-PAN asymmetric membranes. All prepared photo-catalytic membranes where capable of completely inactivating E. coli ATCC 8739 within 120 minutes of exposure and inactivation rate increased with increasing N-TiO2 photo-catalyst loading. However, there was an indication from the results obtained that N-TiO2 supported on PMAA-g-PVDF/ PAN showed a higher inactivation rate of E. coli ATCC 8739 compared to N-TiO2-PAN and N-TiO2-PVDF membranes. The 1 % N-TiO2-PMAA-g-PVDF/ PAN membranes gave the highest pure water flux (421.83 L/m2h). This increase (PVDF = 30.50 L/m2h, PAN = 73.85 L/m2h) in pure water flux is owedb to PMAA grafting as well as addition of N-TiO2. These modifications resulted in an increased membrane surface hydrophilicity, which promoted permeation of pure water through the membrane structure. A high bovine serum albumin (BSA) rejection (76.5 %) was noted and can be attributed to steric hindrance brought about by PMAA side chains which prevented the bulky BSA molecules from attaching to the membrane surface for PMAA-g-PVDF/ PAN membranes. However, the supporting porous sub-layer of an asymmetric membrane seemed to play a very important role in the overall permeability of a membrane. PVDF membranes are highly hydrophobic hence they gave a very low pure water flux.
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