Prevalence of pathogenic Escherichia coli strains in the final effluents of four wastewater treatment plants in the Eastern Cape Province of South Africa
- Authors: Seti, Nozuko Zukiswa
- Date: 2014
- Subjects: Escherichia coli -- South Africa -- Eastern Cape , Bacterial diseases -- Pathogenesis , Sewage -- Purification -- South Africa -- Eastern Cape , Sewage disposal plants -- South Africa -- Eastern Cape , Whole effluent toxicity testing -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11286 , http://hdl.handle.net/10353/d1019808 , Escherichia coli -- South Africa -- Eastern Cape , Bacterial diseases -- Pathogenesis , Sewage -- Purification -- South Africa -- Eastern Cape , Sewage disposal plants -- South Africa -- Eastern Cape , Whole effluent toxicity testing -- South Africa -- Eastern Cape
- Description: Water is an essential need that stimulates health and well being. Increase in population size and urbanization negatively affect water resources due to high demands of effluent outputs. Wastewater is an important reservoir for Escherichia coli and can present significant acute toxicity if released into receiving water sources without being adequately treated. E. coli is used as indicator organism for the detection of faecal contamination. These strains have been considered to be one of the primary causes of diarrhoeal infections worldwide. The present study was conducted between September 2012 and June 2013 to assess the prevalence of pathogenic E. coli strains in the final effluents of four wastewater treatment plants in Chris Hani and Buffalo City Municipalities in the Eastern Cape Province of South Africa. Standard membrane filtration technique was used for bacteriological analysis and molecular based technique was used for identification of E. coli pathotypes. The results were recorded in colony forming units/100 ml. Faecal coliforms ranged between 0-9.6×10³ CFU/100 ml for the wwtp-Q and E. coli densities ranged between 0-8.4×10³ CFU/100ml. Faecal coliforms ranged between 4×10²-9.7×10³ CFU/100 ml for wwtp-M and E. coli densities ranged between 1.2×10¹-8.4×10³ CFU/100 ml. The wwtp-E showed to have bacterial counts of faecal coliforms ranging between 4.0×10³-8.2×10³ CFU/100 ml and E. coli densities ranging between 3.5×10¹-7.1×10³ CFU/100 ml. The WWTP-K in this study was only assessed for the presence of E. coli. Faecal coliforms were assessed by the other members of the group. This plant showed to have E. coli densities ranging between 0-7.5×10²CFU/100 ml. A total of 200 presumptive E. coli isolates were subjected to screening by conventional PCR in which (29%) of the wwtp-M isolates were positively identified as E. coli, (16%) of the wwtp-K, (22%) of the wwtp-Q and (34%) of the wwtp-E isolates were positively confirmed as E. coli. A total of 100 randomly selected E. coli isolates were characterised into different pathotypes. (16%) of positive isolates were detected as EPEC and 11% were detected as UPEC strains. There was no detection for the ETEC strains. Antibiotic susceptibility patterns of E. coli strains showed high levels of resistance to Penicillin G, Erythromycin, Tetracycline and Sulfamethoxazole. High levels of Susceptibility were observed in antibiotics such as Chloramphenicol, Amoxicillin and Tetracycline. The results of this study reveal that the plants were above the recommended Standard limit of zero CFU/100 ml for effluents meant to be discharge into receiving water sources. This study reveals inadequacy of the plants studied to produce effluents of acceptable quality.
- Full Text:
- Date Issued: 2014
- Authors: Seti, Nozuko Zukiswa
- Date: 2014
- Subjects: Escherichia coli -- South Africa -- Eastern Cape , Bacterial diseases -- Pathogenesis , Sewage -- Purification -- South Africa -- Eastern Cape , Sewage disposal plants -- South Africa -- Eastern Cape , Whole effluent toxicity testing -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11286 , http://hdl.handle.net/10353/d1019808 , Escherichia coli -- South Africa -- Eastern Cape , Bacterial diseases -- Pathogenesis , Sewage -- Purification -- South Africa -- Eastern Cape , Sewage disposal plants -- South Africa -- Eastern Cape , Whole effluent toxicity testing -- South Africa -- Eastern Cape
- Description: Water is an essential need that stimulates health and well being. Increase in population size and urbanization negatively affect water resources due to high demands of effluent outputs. Wastewater is an important reservoir for Escherichia coli and can present significant acute toxicity if released into receiving water sources without being adequately treated. E. coli is used as indicator organism for the detection of faecal contamination. These strains have been considered to be one of the primary causes of diarrhoeal infections worldwide. The present study was conducted between September 2012 and June 2013 to assess the prevalence of pathogenic E. coli strains in the final effluents of four wastewater treatment plants in Chris Hani and Buffalo City Municipalities in the Eastern Cape Province of South Africa. Standard membrane filtration technique was used for bacteriological analysis and molecular based technique was used for identification of E. coli pathotypes. The results were recorded in colony forming units/100 ml. Faecal coliforms ranged between 0-9.6×10³ CFU/100 ml for the wwtp-Q and E. coli densities ranged between 0-8.4×10³ CFU/100ml. Faecal coliforms ranged between 4×10²-9.7×10³ CFU/100 ml for wwtp-M and E. coli densities ranged between 1.2×10¹-8.4×10³ CFU/100 ml. The wwtp-E showed to have bacterial counts of faecal coliforms ranging between 4.0×10³-8.2×10³ CFU/100 ml and E. coli densities ranging between 3.5×10¹-7.1×10³ CFU/100 ml. The WWTP-K in this study was only assessed for the presence of E. coli. Faecal coliforms were assessed by the other members of the group. This plant showed to have E. coli densities ranging between 0-7.5×10²CFU/100 ml. A total of 200 presumptive E. coli isolates were subjected to screening by conventional PCR in which (29%) of the wwtp-M isolates were positively identified as E. coli, (16%) of the wwtp-K, (22%) of the wwtp-Q and (34%) of the wwtp-E isolates were positively confirmed as E. coli. A total of 100 randomly selected E. coli isolates were characterised into different pathotypes. (16%) of positive isolates were detected as EPEC and 11% were detected as UPEC strains. There was no detection for the ETEC strains. Antibiotic susceptibility patterns of E. coli strains showed high levels of resistance to Penicillin G, Erythromycin, Tetracycline and Sulfamethoxazole. High levels of Susceptibility were observed in antibiotics such as Chloramphenicol, Amoxicillin and Tetracycline. The results of this study reveal that the plants were above the recommended Standard limit of zero CFU/100 ml for effluents meant to be discharge into receiving water sources. This study reveals inadequacy of the plants studied to produce effluents of acceptable quality.
- Full Text:
- Date Issued: 2014
An assessment of needle ice, snowfall and the zero-curtain effect and its relationship with soil frost dynamics on sub-Antartic Marion Island
- Authors: Zilindile, Mphumzi Brooklyn
- Date: 2013
- Subjects: Snow -- Prince Edward Islands -- Marion Island , Frost -- Prince Edward Islands -- Marion Island , Ice -- Prince Edward Islands -- Marion Island , Marion Island (Prince Edward Islands) -- Description and travel
- Language: English
- Type: Thesis , Masters , MSc (Geography)
- Identifier: vital:11515 , http://hdl.handle.net/10353/d1006908 , Snow -- Prince Edward Islands -- Marion Island , Frost -- Prince Edward Islands -- Marion Island , Ice -- Prince Edward Islands -- Marion Island , Marion Island (Prince Edward Islands) -- Description and travel
- Description: This study aims to uncover the synoptic weather circulation pattern which is associated with the occurrence of needle ice, snowfall and the zero-curtain effect. The method of study was done through an intensive ground climate measurement campaign from April 2008 to May 2009 with a temperature logger installed throughout the recording period. Results from data analyses indicate that the complex changes in climate parameters may lead to an equally complex response in terms of spatial soil frost dynamics and its direct and indirect effects on soil sediment displacement and ecosystem dynamics. Field evidence in the study suggests that on Marion Island needle ice developed in temperatures as high as -0.2 ºC in strong winds. This confirms that the wet environment of Marion Island, which is dominated by diurnal soil frost is fundamentally different from seasonal frost and permafrost environments. The scoria material is susceptible to needle ice growth and the compacted soil alters the micro-climatology of the affected area making it more susceptible to the formation of needle ice. Soil moisture for needle ice formation and growth is provided by the misty conditions associated with the advent of the cold front (pre-cyclonic). Furthermore, observations of needle ice on Marion show that needles are mostly clear with no sediment inclusion. This is indicative of needle ice formation that has not been interrupted by a shortage of moisture. The zero-curtain effect on Marion Island can occur either as a response to the thawing of the soil after the seasonal freeze. The synoptic assessment of snowfall on Marion Island indicates that; snowfall is associated with the passage of a cold front linked to a strong meridional system of low pressure just south of the island.
- Full Text:
- Date Issued: 2013
- Authors: Zilindile, Mphumzi Brooklyn
- Date: 2013
- Subjects: Snow -- Prince Edward Islands -- Marion Island , Frost -- Prince Edward Islands -- Marion Island , Ice -- Prince Edward Islands -- Marion Island , Marion Island (Prince Edward Islands) -- Description and travel
- Language: English
- Type: Thesis , Masters , MSc (Geography)
- Identifier: vital:11515 , http://hdl.handle.net/10353/d1006908 , Snow -- Prince Edward Islands -- Marion Island , Frost -- Prince Edward Islands -- Marion Island , Ice -- Prince Edward Islands -- Marion Island , Marion Island (Prince Edward Islands) -- Description and travel
- Description: This study aims to uncover the synoptic weather circulation pattern which is associated with the occurrence of needle ice, snowfall and the zero-curtain effect. The method of study was done through an intensive ground climate measurement campaign from April 2008 to May 2009 with a temperature logger installed throughout the recording period. Results from data analyses indicate that the complex changes in climate parameters may lead to an equally complex response in terms of spatial soil frost dynamics and its direct and indirect effects on soil sediment displacement and ecosystem dynamics. Field evidence in the study suggests that on Marion Island needle ice developed in temperatures as high as -0.2 ºC in strong winds. This confirms that the wet environment of Marion Island, which is dominated by diurnal soil frost is fundamentally different from seasonal frost and permafrost environments. The scoria material is susceptible to needle ice growth and the compacted soil alters the micro-climatology of the affected area making it more susceptible to the formation of needle ice. Soil moisture for needle ice formation and growth is provided by the misty conditions associated with the advent of the cold front (pre-cyclonic). Furthermore, observations of needle ice on Marion show that needles are mostly clear with no sediment inclusion. This is indicative of needle ice formation that has not been interrupted by a shortage of moisture. The zero-curtain effect on Marion Island can occur either as a response to the thawing of the soil after the seasonal freeze. The synoptic assessment of snowfall on Marion Island indicates that; snowfall is associated with the passage of a cold front linked to a strong meridional system of low pressure just south of the island.
- Full Text:
- Date Issued: 2013
Impact assessment of Transversal Training Management Agency (TTMA) training in performance improvement of the Eastern Cape provincial department of basic education (2005-2010)
- Nontshokweni, Princess Nombeko
- Authors: Nontshokweni, Princess Nombeko
- Date: 2011
- Subjects: Employees -- Training of -- South Africa -- Eastern Cape , Performance -- Management , Career development -- South Africa -- Eastern Cape , Employees -- Rating of -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: vital:11642 , http://hdl.handle.net/10353/d1001251 , Employees -- Training of -- South Africa -- Eastern Cape , Performance -- Management , Career development -- South Africa -- Eastern Cape , Employees -- Rating of -- South Africa -- Eastern Cape
- Description: Training is widely conducted in organizations and is actively encouraged by the recent legislation in South Africa. Millions of Rands are spent building human resource capabilities. Organizations therefore need to know whether this investment in training is bearing fruit in terms of changes in individual performance and overall impact on service delivery. The need to improve Transversal Training Management Agency (TTMA) training programmes and skills development impact to government departments has triggered the survey. Three interdependent themes are explored: training evaluation in `government departments, influence of non-training factors and human dynamics between stakeholders in the training evaluation process. Structured questionnaires, based on best practises in literature were administered to key stakeholders involved in TTMA training programmes. Training managers and the Office of the Premier (OTP) Human Resource Development (HRD) officials were interviewed, while supervisors, trainees and trainers verified the data by post. Data were collected from the Department of Basic Education, Eastern Cape (EC), TTMA trainers and trainees. Findings show that The Department of Basic Education in the EC does not fully follow a system’s approach. Evaluations done during classroom sessions focus mainly on the reaction of participants to training and not on the behaviour change in the workplace. Training participants are not prepared for training; sometimes they do not even know why they attend training. Some trainees go to training just to get certificates that increase their CV’s for promotion purposes or to run away from the stressful work environment and not for individual growth. Recommendations to use a systemic evaluation approach and involvement of trainees in their career development process are made. Further research is recommended on the managing of non-training factors that impede learning transfer.
- Full Text:
- Date Issued: 2011
- Authors: Nontshokweni, Princess Nombeko
- Date: 2011
- Subjects: Employees -- Training of -- South Africa -- Eastern Cape , Performance -- Management , Career development -- South Africa -- Eastern Cape , Employees -- Rating of -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: vital:11642 , http://hdl.handle.net/10353/d1001251 , Employees -- Training of -- South Africa -- Eastern Cape , Performance -- Management , Career development -- South Africa -- Eastern Cape , Employees -- Rating of -- South Africa -- Eastern Cape
- Description: Training is widely conducted in organizations and is actively encouraged by the recent legislation in South Africa. Millions of Rands are spent building human resource capabilities. Organizations therefore need to know whether this investment in training is bearing fruit in terms of changes in individual performance and overall impact on service delivery. The need to improve Transversal Training Management Agency (TTMA) training programmes and skills development impact to government departments has triggered the survey. Three interdependent themes are explored: training evaluation in `government departments, influence of non-training factors and human dynamics between stakeholders in the training evaluation process. Structured questionnaires, based on best practises in literature were administered to key stakeholders involved in TTMA training programmes. Training managers and the Office of the Premier (OTP) Human Resource Development (HRD) officials were interviewed, while supervisors, trainees and trainers verified the data by post. Data were collected from the Department of Basic Education, Eastern Cape (EC), TTMA trainers and trainees. Findings show that The Department of Basic Education in the EC does not fully follow a system’s approach. Evaluations done during classroom sessions focus mainly on the reaction of participants to training and not on the behaviour change in the workplace. Training participants are not prepared for training; sometimes they do not even know why they attend training. Some trainees go to training just to get certificates that increase their CV’s for promotion purposes or to run away from the stressful work environment and not for individual growth. Recommendations to use a systemic evaluation approach and involvement of trainees in their career development process are made. Further research is recommended on the managing of non-training factors that impede learning transfer.
- Full Text:
- Date Issued: 2011
Randomization in a two armed clinical trial: an overview of different randomization techniques
- Authors: Batidzirai, Jesca Mercy
- Date: 2011
- Subjects: Clinical trials -- Statistical methods , Biometry , Sampling (Statistics)
- Language: English
- Type: Thesis , Masters , MSc (Biostatistics and Epidemiology)
- Identifier: vital:11781 , http://hdl.handle.net/10353/395 , Clinical trials -- Statistical methods , Biometry , Sampling (Statistics)
- Description: Randomization is the key element of any sensible clinical trial. It is the only way we can be sure that the patients have been allocated into the treatment groups without bias and that the treatment groups are almost similar before the start of the trial. The randomization schemes used to allocate patients into the treatment groups play a role in achieving this goal. This study uses SAS simulations to do categorical data analysis and comparison of differences between two main randomization schemes namely unrestricted and restricted randomization in dental studies where there are small samples, i.e. simple randomization and the minimization method respectively. Results show that minimization produces almost equally sized treatment groups, but simple randomization is weak in balancing prognostic factors. Nevertheless, simple randomization can also produce balanced groups even in small samples, by chance. Statistical power is also improved when minimization is used than in simple randomization, but bigger samples might be needed to boost the power.
- Full Text:
- Date Issued: 2011
- Authors: Batidzirai, Jesca Mercy
- Date: 2011
- Subjects: Clinical trials -- Statistical methods , Biometry , Sampling (Statistics)
- Language: English
- Type: Thesis , Masters , MSc (Biostatistics and Epidemiology)
- Identifier: vital:11781 , http://hdl.handle.net/10353/395 , Clinical trials -- Statistical methods , Biometry , Sampling (Statistics)
- Description: Randomization is the key element of any sensible clinical trial. It is the only way we can be sure that the patients have been allocated into the treatment groups without bias and that the treatment groups are almost similar before the start of the trial. The randomization schemes used to allocate patients into the treatment groups play a role in achieving this goal. This study uses SAS simulations to do categorical data analysis and comparison of differences between two main randomization schemes namely unrestricted and restricted randomization in dental studies where there are small samples, i.e. simple randomization and the minimization method respectively. Results show that minimization produces almost equally sized treatment groups, but simple randomization is weak in balancing prognostic factors. Nevertheless, simple randomization can also produce balanced groups even in small samples, by chance. Statistical power is also improved when minimization is used than in simple randomization, but bigger samples might be needed to boost the power.
- Full Text:
- Date Issued: 2011
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