3. Electronic Theses and Dissertations (ETDs) - All submissions
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Item Electrocatalytic detection of drugs of abuse using onion-like carbon based electrocatalysts(2024) Ehirim, Tobechukwu JusticeSubstance abuse is a serious problem worldwide. Among abused substances, tramadol and alcohol are one of many. There is an urgent need to use electrochemical method for their detection since electrochemistry methods are simple, low-cost, high sensitivity and can easily be miniaturised. This PhD work reports the first investigation on the application of nanodiamond-derived onion-like carbons (OLC) and conductive carbon black (CB) as (i) electrocatalysts for the detection of tramadol, and (ii) as support materials for nano-sized palladium electrocatalysts (Pd/OLC, Pd/CB, Pd-CeO2/OLC) for the detection of ethanol. The catalysts were characterised with X-ray diffraction (XRD), Raman, Brunauer– Emmett–Teller (BET), Thermal gravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). For the detection of tramadol, OLC gave the best sensing performance compared to CB. Theoretical calculations (DFT simulations) predict that OLC is better because it allows for weaker interaction energy with tramadol (Ead = -26.656 eV) than CB (Ead = -40.174 eV). OLC-modified glassy carbon electrode (GCE-OLC) shows a wide linear calibration curve (55 – 392 M), high sensitivity (0.0315 A /M), low limit of detection (LoD) and quantification (LoQ) of 3.8 and 12.7 M, respectively. OLCmodified screen-printed electrode (SPE-OLC) successfully detected tramadol in real tramadol drug and human serum. The OLC-based electrochemical sensor promises to be useful for sensitive and accurate detection of tramadol in clinics, quality control and routine quantification of tramadol in pharmaceutical formulations. For the oxidation and detection of ethanol, Pd/CB, Pd/OLC and Pd-CeO2/OLC, were studied as catalysts. In comparison, adding ceria (CeO2) to Pd/OLC, the performance was enhanced significantly than in carbon-only support for palladium. GCE/PdCeO2/OLC shows the best electrocatalytic performance (i.e., high current density, fast electron transport, etc). DFT calculation, supported by XPS and HRTEM data, predict that this high activity may be related to CeO2 modulating the electronic properties of the catalyst. GCE/Pd-CeO2/OLC gave wide linear range for ethanol sensing (38.5 – 286 mM), excellent sensitivity (0.00024 mA mM-1 ) and LoD of ~ 8.7 mM. The GCE/Pd-CeO2/OLC shows excellent potential for application in real samples of commercial alcoholic beverages and human serum, with satisfactory recoveries (89 – 108 %).Item A multilevel model of self-rated health in Gauteng: a comorbidity study(2019) Bhat, IshwariThe report reviewed the self-rated health of Gauteng’s comorbid health in 2015. The outcome variable of this report was defined as the self-rated comorbid health of Gauteng. A multilevel approach examined factors closely associated with comorbid health using both individual and community-level variables. The report addresses the symbiotic relationship between comorbidity prevalence and Gauteng’s socioeconomic conditions that foster poor health. South African healthcare has been characterised by its increasing comorbidity of communicable diseases. As the prevalence of comorbidity varies between spaces, it becomes increasingly important to examine social environments. The aim of this study estimated the prevalence of comorbidity, and determined the factors associated with self-reported comorbidity in the Gauteng province of South Africa. A multilevel model approach was used in this cross-sectional study. Primary data was provided by the Gauteng City-Region Observatory from the Quality of Live survey (QoL) in 2015, it comprised 30 002 participants above the ages of 18 years, who were selected through numerous sampling stages. enumeration areas (EA) were drawn using probability proportional to size as the primary sampling unit. Comorbidity was illustrated as classes of two, three and four-or-more. Prevalence was estimated as a proportion of comorbid health conditions from the health section of the survey. Spatial autocorrelation was used to detect spatial patterns of comorbidity. Regression models were used to determine factors closely associated with comorbidity in Gauteng. The estimated prevalence of self-reported two comorbidities (hypertension and diabetes) was 8.97%, three comorbidities (hypertension, diabetes and influenza/pneumonia) was 3.01% and four-or-more comorbidities (hypertension, heart disease/stroke, diabetes and asthma) was 0.96%. Ordinary Least Squares (OLS) models provided the first step for regression analysis, wherein only two comorbidities illustrated spatial dependence among the residual errors. The spatial error model of two comorbidities was interpreted as the most accurate model owing to the high Hausman test p-value. Three comorbidities and four-or-more comorbidities indicated no spatial dependence among the residuals, reiterating the OLS model as the most appropriate regression model for each class. Conventional multilevel models illustrated that self-rated comorbidity prevalence was more likely to report two comorbidities (n=829,8.97%) for quality of property, child malnutrition, low exercise frequency, high stress and The report reviewed the self-rated health of Gauteng’s comorbid health in 2015. The outcome variable of this report was defined as the self-rated comorbid health of Gauteng. A multilevel approach examined factors closely associated with comorbid health using both individual and community-level variables. The report addresses the symbiotic relationship between comorbidity prevalence and Gauteng’s socioeconomic conditions that foster poor health. South African healthcare has been characterised by its increasing comorbidity of communicable diseases. As the prevalence of comorbidity varies between spaces, it becomes increasingly important to examine social environments. The aim of this study estimated the prevalence of comorbidity, and determined the factors associated with self-reported comorbidity in the Gauteng province of South Africa. A multilevel model approach was used in this cross-sectional study. Primary data was provided by the Gauteng City-Region Observatory from the Quality of Live survey (QoL) in 2015, it comprised 30 002 participants above the ages of 18 years, who were selected through numerous sampling stages. enumeration areas (EA) were drawn using probability proportional to size as the primary sampling unit. Comorbidity was illustrated as classes of two, three and four-or-more. Prevalence was estimated as a proportion of comorbid health conditions from the health section of the survey. Spatial autocorrelation was used to detect spatial patterns of comorbidity. Regression models were used to determine factors closely associated with comorbidity in Gauteng. The estimated prevalence of self-reported two comorbidities (hypertension and diabetes) was 8.97%, three comorbidities (hypertension, diabetes and influenza/pneumonia) was 3.01% and four-or-more comorbidities (hypertension, heart disease/stroke, diabetes and asthma) was 0.96%. Ordinary Least Squares (OLS) models provided the first step for regression analysis, wherein only two comorbidities illustrated spatial dependence among the residual errors. The spatial error model of two comorbidities was interpreted as the most accurate model owing to the high Hausman test p-value. Three comorbidities and four-or-more comorbidities indicated no spatial dependence among the residuals, reiterating the OLS model as the most appropriate regression model for each class. Conventional multilevel models illustrated that self-rated comorbidity prevalence was more likely to report two comorbidities (n=829,8.97%) for quality of property, child malnutrition, low exercise frequency, high stress and low-income bracket in Gauteng. Self-rated comorbidity prevalence was more likely to report three comorbidities (n=76, 3.017%) for migrated from another province, family living nearby, adult malnutrition, medium to high stress, low-income bracket and female in Gauteng. Results of four-or-more comorbidities were defined by the limitation that data set was too small for regression analysis. Comorbidity has a complexity in nature, in that it both influenced by Gauteng socioeconomic environments as well as influenced Gauteng health. Comorbidity became a challenge for Gauteng in addressing complexity, accessibility and cost-effectiveness. It was anticipated that these findings may advise policy interventions in mitigating health disparities in the broader context of South Africa.Item The frequency of positive urine multi-drug tests among outpatients with both HIV and psychiatric illnesses at Luthando Clinic, Chris Hani Baragwanath academic hospital, Soweto, South Africa(2019) Khabisi, Moeketsi Elliothere is evidence from both local and international studies on the high levels of substance use in patients with mental illnesses or those diagnosed with HIV (Human Immunodeficiency Virus). However, there is limited data in South Africa (SA) on the level of substance use, particularly cannabis, in patients who have been diagnosed with both HIV and psychiatric illness. The aim of the study is to describe the frequency of positive multi-drug urine tests for a duration of 6 months (1st January-30th June 2014) among outpatients with both psychiatric illness and HIV at the Luthando Neuropsychiatric clinic. Methods: This was a retrospective record review of all patients who attended Luthando clinic within the 6 month study period. A record sheet with demographics, multi-drug urine test (MDUT) results and clinical variables were completed for each patient and was thereafter subsequently entered into a statistical software programme SAS version 9.4 Windows database. For categorical data, a descriptive analysis was used, while Chi square and Fisher exact tests were used for evaluating associations between MDUT results and clinical variables. Cramer’s V and Phi coefficient were employed to measure the association’s strengths respectively. A 5% precision and 95% confidence level were used. Results: A total of 337 file records were reviewed. The prevalence of positive MDUTs was 36.4% (n=118). The most common substance used was cannabis at 94.9%. There was a significant association between positive MDUTs and young, male participants (p=0.030 and p=0.0001, respectively). There was a significant association between a positive MDUT and poor viral suppression (p=0.010), as well as the patient’s duration on antiretroviral treatment (ART), with a shorter duration on ART being related to use of substances (p=0.036). There was also a significant association between MDUT outcome and psychiatric diagnoses, specifically bipolar disorder due to HIV and substance use disorder (p=0.0001 and p=0.0006, respectively). Conclusion: This study demonstrated a high prevalence of substance use with a lower rate of viral suppression among patients attending Luthando Neuropsychiatric clinic. This is of great concern to personal and public health implications, hence such patients must be promptly identified in the course of their illnesses so that they can be effectively managed.Item The impact of alcohol on the different components of working memory(2018) Opperman, IAlcohol consumption related deficits on complex executive functions and short-term memory have been reported in the literature, usually based on group comparisons. A repeated measures design was used, assessing 21 to 35 year old male participants (n = 16) on the Automated Working Memory Assessment’s twelve verbal and visuo-spatial short-term and working memory subtests. A low dose of alcohol (13.6 grams) was administered, breath alcohol concentration (BAC) was measured and subjective feelings of stimulation were assessed on the Brief Biphasic Alcohol Effects Scale (B-BAES). Repeated measures analysis of (co)variance models indicated that performance improved on the working memory processing tasks, particularly in the verbal domain. This may have been related to changes in attention functions, stimulus evaluation task demands and tacit recall. However, several of the short-term memory tasks deteriorated under the experimental condition, where Word Recall was significant when age was controlled for. This may have been due to alcohol-related changes in stimulus representations. Partial correlation coefficients suggested that higher BACs were related to deficits in performance if participant age was controlled for. The structure of the B-BAES was consistent with the literature, but subjective feelings of stimulation were not associated with performance changes. Shorter test-retest delays were slightly associated with improved performance, but the research data did not fully support practice effects or a mitigating influence of alcohol consumption. Based on the findings, the specific influence of alcohol consumption on working memory could depend on methodological design, task types, memory domain and other sources of variance.Item Attitudes towards individuals with substance use disorders: the impact of knowledge and the moderating effects of exposure(2018) Dennis, SimoneThe current study aimed to explore whether or not levels of substance use disorder-related knowledge is associated with attitudes towards people with Substance Use Disorders (SUDs) through a convenience sample of young adult psychology students registered at the University of the Witwatersrand (Wits). This research particularly sought to explore the potential moderating effects of exposure to people with SUDs in this relationship. METHOD: The convenience sample employed in this study comprised 253 participants, all of whom completed an online survey which included a brief demographic questionnaire, a questionnaire measuring SUD-related knowledge, a questionnaire measuring SUD-related exposure, and a questionnaire measuring SUD-related attitudes. RESULTS: The results of the study indicated that, on average, the current sample evidenced positive SUD-related attitudes across more domains than not. Additionally, SUD-related knowledge amongst participants in this study appeared to be somewhat limited. The results suggest that exposure to SUDs amongst the participants is varied and that significant links exist between SUD-related attitudes and exposure. Furthermore, the results call to question the extent to which SUD-related knowledge alone impacts on attitudes towards SUDs. CONCLUSIONS: The primary implication of these findings relates to the SUD-specific training of health professionals. This research suggests the inadequacy of such knowledge-focused training and motivates for the incorporation of exposure to real individuals living with SUDs in such training programmes.Item A phenomenological study of how people with co-occurring disorders have managed to achieve a state of full recovery(2016-07-27) Heald, AlistairThis study was aimed at an in-depth exploration of the recovery experiences of a group of 12 individuals who attended 12 step self-help groups situated in different regions in Johannesburg. 12-step self-help groups are presently the largest clinical supplements in the world. Ongoing discussions with the relevant representatives from the fellowships of Alcoholics Anonymous (AA) and Narcotics Anonymous (NA) were utilised in order to gain access to this population of people. These 12 individuals suffered from substance dependence and one or more co-occurring disorders (CODs) and were interviewed in semi-structured interviews about how their lives had changed since they had achieved a state of recovery and about some of the difficulties they had experienced since the point at which they had achieved remission from their substance-related disorder. The study also focused on the therapeutic aids that the participants had found useful during their time in recovery. In this study, CODs refers to the existence of at least one substance-related disorder and at least one psychiatric disorder in the same individual. The overarching methodological framework that was used in the study was phenomenological. It was evident from the study that the road to recovery is fraught with many challenges that the recovering individual needs to negotiate and that very often there is no information available on what the best course of action to follow is. In conclusion it is evident that recovering addicts, especially those that have been diagnosed with one or more CODs often require on going support and care if they are to continue on their journey of recoveryItem Factors influencing the sustainability of local drug action committees in the Free State Province : case study of Mangaung Municipality.(2014-09-05) Matsenyane, Leloko EdwinThe Local Drug Action Committee (LDAC) is the closest body to the community which is made up of individuals from different stakeholders at a local level to coordinate the activities aimed at the prevention of substance abuse and illicit drug trafficking within the communities. Since the implementation of the committees, the sustainability of these committees has been a challenge in the Free State Province. The study endeavoured to explore factors which influence the sustainability of these committees in the Free State Province. A qualitative research approach that was explorative and descriptive in nature was employed. A case study design was used. Purposive sampling was applied to select the participants from two LDACs in Mangaung Municipality. A semi-structured interview schedule was used to collect the data during individual in-depth interviews with five participants. Thematic content analysis was used to analyse the data. The main findings indicated that there was a lack of knowledge among the committee members about their roles, responsibilities and mandates. Their inability to coordinate the stakeholder activities as well as the limited knowledge about the relationship between the Free State Mini Drug Master Plan (FSMDMP) and the LDACs also appeared to be challenging. The main conclusions drawn from the study are that despite the excellent structure of the LDACs to coordinate the implementation of the FSMDMP, the members of the LDACs are neither knowledgeable about nor capacitated to fulfil their roles and responsibilities to meet the intended requirements and implement the activities of the FSMDMP, factors which hamper sustainability. The lack of financial support from Government to fund the activities of the LDACs in the Province is another major impediment in terms of sustainability.Item Exploring employees' perceptions of the effectiveness of BSI Steel's company drug and alcohol policy.(2012-09-04) Nyarko, GiftyNo abstract present of CD.Item Understanding the work experiences, coping strategies and organisational retention of social workers in Gauteng in-patient substance abuse treatment centres.(2009-01-07T09:51:22Z) Vermeulen, AlexandrinaSouth Africa has experienced a drastic shortage of social workers. This shortage has affected many social welfare organizations, particularly those who offer services in the area of substance abuse. According to a recent study conducted by Earle (2008) many reasons could be ascribed to the high social work turnover, these include: poor working conditions; poor compensation of work; lack of resources and support; and increased demands for services. Hence, social workers are experiencing work stress, burnout and compassion fatigue taxing their personal and professional coping strategies which could lead to staff turnover. The primary aim of this study was to understand the work experiences, coping strategies and organisational retention of social workers in Gauteng inpatient substance abuse treatment centres. The study had an exploratorydescriptive design, incorporating both quantitative and qualitative paradigms to explore the work environment of the organisations and participants. Purposive sampling was used to select and divide the participants into three categories: entry level social workers; experienced social workers and social workers that had left the substance abuse field. Data was collected through conducting indepth interviews and through a questionnaire completed by the representatives from in-patient substance abuse treatment centres. This questionnaire was piloted with an in-patient treatment centre in KwaZulu Natal. The results of the quantitative data were analysed using descriptive statistics, which were illustrated via tables and figures and the qualitative data were analysed using thematic content analysis. The main findings of this study confirmed most of the reasons for work stress and burnout that may lead to staff turnover identified in previous studies by Ross (1997) and Earle (2008). These findings are incorporated into a retention model developed by the researcher. The model incorporated five stages: stage one focussed on the reasons for entering the substance abuse field (personal interests, undergraduate studies and/or accidental); stage two explored preparation of social workers by organisations after entry to the field; stage three identified four general factors that effects the sustainability of social workers (external/environmental influences, organisational factors, the type of client population, career opportunities and personal factors); stage four explained the individual differences in coping responses (negative or positive) to job stress either through fight responses, self-care strategies for retention or flight responses, staff turnover; lastly, stage five focussed on what organisations can do to reduce staff turnover. These findings can assist the occupational social worker to identify these retention challenges and develop strategies to reduce the risk of staff turnover.