78 research outputs found

    Electrospun nanofibers : an alternative sorbent material for solid phase extraction

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    The work described in the thesis seeks to lay a foundation for a better understanding of the use of electrospun nanofibers as a sorbent material. Three miniaturised electrospun nanofiber based solid phase extraction devices were fabricated. For the first two, 10 mg of electrospun polystyrene fibers were used as a sorbent bed for a micro column SPE device (8 mm bed height in a 200 μl pipette tip) and a disk (I) SPE device (5 mm 1 mm sorbent bed in a 1000 μl SPE barrel). While for the third, 4.6 mg of electrospun nylon nanofibers were used as a sorbent bed for a disk (II) SPE device, (sorbent bed consisting of 5 5 mm 350 μm stacked disks in a 500 μl SPE barrel). Corticosteroids were employed as model analytes for performance evaluation of the fabricated SPE devices. Quantitative recoveries (45.5-124.29 percent) were achieved for all SPE devices at a loading volume of 100 μl and analyte concentration of 500 ng ml-1. Three mathematical models; the Boltzmann, Weibull five parameter and the Sigmoid three parameter were employed to describe the break through profiles of each of the sorbent beds. The micro column SPE device exhibited a breakthrough volume of 1400 μl, and theoretical plates (7.98-9.1) while disk (I) SPE device exhibited 400-500 μl and 1.39-2.82 respectively. Disk (II) SPE device exhibited a breakthrough volume of 200 μl and theoretical plates 0.38-1.15. It was proposed that the formats of future electrospun nanofiber sorbent based SPE devices will be guided by mechanical strength of the polymer. The study classified electrospun polymer fibers into two as polystyrene type (relatively low mechanical strength) and nylon type (relatively high mechanical strength)

    Investigating menstrual hygiene facilities and education opportunities for female learners in the Western Cape

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    The completed study investigated menstrual hygiene facilities and the related education opportunities presented for female learners in selected primary and secondary schools in the Ocean View area of the Western Cape Province of South Africa. Despite female learners’ school enrolment having improved in the region in recent years, large gender inequality gaps in primary education still exist and are even more evident in secondary education. In South Africa, menstrual hygiene and the inability of female learners to go to school when they are experiencing their periods is not just a sanitation issue, nor is it a physiological one. Rather, it is something that has wider socio-economic implications with historical connotations, given where this country has come from. Furthermore, this study attempted to address some of the gaps in existing, theoretical knowledge and policies, particularly social and educational policy, by investigating how menstruation and puberty-related challenges in the context of poor sanitation and menstrual hygiene facilities were exacerbating gender inequalities in the South African education system. A qualitative research design was used to gain an enriched understanding of the female learners’ perceptions and experiences regarding the state of the menstrual hygiene facilities at their schools and the influence of these facilities on their educational opportunities. This study highlights that menstrual hygiene management continues to receive limited attention in government policies, research priorities, programmes and resource allocation, and the information available to the public tends to be informed by anecdotal evidence. Moreover, most sanitation and hygiene interventions in developing countries are failing to address all needs required for female learners to manage menstruation appropriately in the school environment. Further, sanitation facility design usually does not address the specific needs of women and the girl child. The research findings from the study completed shows that inadequate sanitation and menstrual hygiene facilities impedes the female learners’ ability to make the most of their education opportunities. Consequently, the study suggests that there is a need for a comprehensive social policy approach to address the identified gaps in policies related to menstrual hygiene management in the South African school environment

    Electrospun Nanofiber Based Solid Phase Extraction

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    A mixed methods analysis of tax capacity and tax effort in the Southern African Development Community (SADC)

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    The design of a country’s tax system is important because of the critical role played by taxation in financing public spending towards economic and social development. In this regard, there is need to enhance the understanding of whether current tax systems in the SADC provide sufficient tax revenue to meet public spending needs. This study provides empirical evidence on the outcomes of existing tax systems in the SADC with the aim of offering a basis for normative evaluation of the regions’ tax policies. Literature posits that there are numerous economic and institutional factors that limit the amount of taxes that a country can actually raise. Against this background, the substantive aim of this study was to assess the determinants of tax capacity and tax effort in the SADC in view of providing a pragmatic approach to tax policy design. The methodology of this study involved the use of both quantitative and qualitative analysis (mixed methods approach) where the latter was used to augment the findings of the former. The first phase involved the use of a multi-step procedure to estimate determinants of tax capacity and tax effort using stochastic tax function and unbalanced panel data for 13 SADC countries. The study disentangled the error term to estimates the random-effects separately from tax effort in order to capture the time- invariant country-specific effects. Further, tax effort was classified persistent (long-run) and transient (short-run). The study was able to estimate the determinants of tax effort and to rank each member state according to its tax effort. The second phase involves a narrative analysis of tax legislation in the SADC over the period 2002-2016. The study used budget statements and Acts of parliament as the major sources of information to identify significant changes in tax legislation over this period. The findings of the quantitative analysis indicate that financial deepening, economic development and trade openness influence tax capacity, while corruption and inflation influence tax effort. In addition, the findings show that the region has low persistent tax effort than transient tax effort, implying that improving tax administration has superseded tax policy reforms. This result is augmented by the narrative record which seemingly shows that tax legislation efforts were largely successful in tax administration but rather limited in view of tax policy. In this regard, the study recommends that tax policy design should be informed by the conditions of a country and policy considerations relating to peculiar circumstances to obtain robust tax policies.EconomicsD. Com. (Economics

    Sorption of toxic metal ions in aqueous environment using electrospun polystyrene fibres incorporating diazole ligands

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    Electrospun polystyrene fibres incorporating potassium salts of pyrazole-1-carbodithioate and imidazole-1-carbodithioate were employed as sorbents for heavy metals from aqueous environments. The equilibrating time, initial metal concentrations and sorbent mass for optimal adsorption were 40 min, 5 mg/ℓ and 8 mg, respectively. The optimal pH for metal ion uptake was between 6.3 and 9.0 and was found to be dependent on the basicity of the ligands. Protonation constants for the ligands in aqueous solutions were determined potentiometrically; pK of the imidazole was 6.82 while that of the pyrazole was 3.36. The efficiencies of adsorption and desorption of metals on the imidazolyl-incorporated sorbents were more than 95%, up to the fifth cycle of usage. The limits of quantification were ≤ 0.0145 mg/ℓ for all the metals. Accuracy of the determinations, expressed as relative error between the certified and observed values of certified reference groundwater samples was ≤ 0.2% with relative standard deviations < 3%. Electrospun polystyrene fibres incorporating imidazoles proved to be efficient sorbents for divalent heavy metal ions in aqueous environments as their efficiencies exceeded those of chitosan microspheres, ion-imprinted composites, amino-functionalised mesoporous materials and most of the biomass-based sorbents previously reported on.Keywords: electrospinning, polystyrene, heavy metals, diazol

    Availability and use of therapeutic interchange policies in managing antimicrobial shortages among South African public sector hospitals; findings and implications

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    Background: Therapeutic interchange policies in hospitals are useful in dealing with antimicrobial shortages and minimising resistance rates. The extent of antimicrobial shortages and availability of therapeutic interchange policies is unknown among public sector hospitals in South Africa. This study aimed to ascertain the extent and rationale for dealing with antimicrobial shortages and describe policies or guidelines and the role of pharmacists in the process. Methods: A quantitative and descriptive study was conducted with a target population of 403 public sector hospitals. Data were collected from hospital pharmacists using an electronic questionnaire via SurveyMonkeyTM. Results: The response rate was 33.5% and most (83.3%) hospitals had experienced shortages in the previous six months. Antimicrobials commonly reported as out of stock included cloxacillin (54.3%), benzathine benzylpenicillin (54.2%), and erythromycin (39.6%). Reasons for shortages included pharmaceutical companies with supply constraints (85.3%) and an inefficient supply system. Only 42.4% had therapeutic interchange policies, and 88.9% contacted the prescriber when there for substitution. Conclusions: Antimicrobial shortages are prevalent in South African public sector hospitals with the most affected being penicillins and cephalosporins. Therapeutic interchange policies are not available at most hospitals. Effective strategies are required to improve communication between pharmacists and prescribers to ensure that safe, appropriate, and therapeutically equivalent alternatives are available

    A multicenter cross-sectional survey of knowledge, attitude and practices of healthcare professionals towards antimicrobial stewardship in Ghana : findings and implications

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    Antimicrobial stewardship (AMS) programs are part of the key activities that contribute to reducing antimicrobial resistance (AMR). Good knowledge, attitudes, and practices (KAP) among healthcare professionals (HCPs) are essential to improving future antimicrobial use and reducing AMR, which is a priority in Ghana. A multicenter cross-sectional survey was conducted in six public hospitals in Ghana among key HCPs to assess their level of KAP towards AMS using a validated self-administered electronic questionnaire. Data analyses included descriptive and inferential statistics using STATA version 14. Overall, 339 out of 355 HCPs responded to the questionnaire, giving a response rate of 95.5%. Most responders were nurses (n = 256, 78.2%), followed by medical doctors (n = 45, 13.3%). The study recorded both poor knowledge (8.9%) and practice levels (35.4%), as well as a good attitude (78.8%) towards AMS. Ongoing exposure to AMS structured training, exposure to continuous professional development training on AMS in the previous year, and the number of years of working experience were predictors of the HCPs’ level of knowledge (aOR = 3.02 C.I = 1.12–8.11), attitude (aOR = 0.37 C.I = 0.20–0.69) and practice (aOR = 2.09 C.I =1.09–3.99), respectively. Consequently, concentrated efforts must be made to address current low levels of knowledge and poor practices regarding AMS among HCPs in Ghana as part of ongoing strategies in the National Action Plan to reduce AMR

    A narrative review of antibiotic prescribing practices in primary care settings in South Africa and potential ways forward to reduce antimicrobial resistance

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    There are concerns with the current prescribing of antibiotics in both the private and public primary care settings in South Africa. These concerns need to be addressed going forward to reduce rising antimicrobial resistance (AMR) rates in South Africa. Concerns include adherence to current prescribing guidelines. Consequently, there is a need to comprehensively summarise current antibiotic utilization patterns from published studies as well as potential activities to improve prescribing, including indicators and antimicrobial stewardship programs (ASPs). Published studies showed that there was an appreciable prescribing of antibiotics for patients with acute respiratory infections, i.e., 52.9% to 78% or more across the sectors. However, this was not universal, with appreciable adherence to prescribing guidelines in community health centres. Encouragingly, the majority of antibiotics prescribed, albeit often inappropriately, were from the ‘Access’ group of antibiotics in the AWaRe (Access/Watch/Reserve) classification rather than ‘Watch’ antibiotics to limit AMR. Inappropriate prescribing of antibiotics in primary care is not helped by concerns with current knowledge regarding antibiotics, AMR and ASPs among prescribers and patients in primary care. This needs to be addressed going forward. However, studies have shown it is crucial for prescribers to use a language that patients understand when discussing key aspects to enhance appropriate antibiotic use. Recommended activities for the future include improved education for all groups as well as regularly monitoring prescribing against agreed-upon guidelines and indicators

    A narrative review of recent antibiotic prescribing practices in ambulatory care in Tanzania : findings and implications

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    Background and objectives: There are concerns with current prescribing of antibiotics in ambulatory care in Tanzania, including both the public and private sectors. These concerns need to be addressed as part of the National Action Plan (NAP) of Tanzania to reduce rising antimicrobial resistance (AMR) rates. Issues and concerns include high rates of prescribing of antibiotics for essentially self-limiting conditions. Consequently, there is a need to address this. As a result, the aims of this narrative review were to comprehensively summarize antibiotic utilization patterns particularly in ambulatory care, their rationale and to suggest ways forward to improve future prescribing. Materials and Methods: We undertook a narrative review of recently published studies and subsequently documented potential activities to improve future prescribing. Potential activities included instigating quality indicators and antimicrobial stewardship programs (ASPs). Results: Published studies have shown that antibiotics are being excessively prescribed in ambulatory care, in up to 95% to 96.3% of presenting cases depending on the sector. This is despite concerns with their appropriateness. High rates of antibiotic prescribing are not helped by variable adherence to current treatment guidelines. There have also been concerns with extensive prescribing of ‘Watch’ antibiotics in the private sector. Overall, the majority of antibiotics prescribed across the sectors, albeit in-appropriately, were typically from the ‘Access’ group of antibiotics in the AWaRe (Ac-cess/Watch/Reserve) classification rather than ‘Watch’ antibiotics to limit AMR. Inappropriate pre-scribing of antibiotics in ambulatory care is linked with current knowledge regarding antibiotics, AMR and ASPs among both prescribers and patients. Recommended activities for the future include improved education for all groups, instigation of updated quality indicators and regular monitoring of prescribing against agreed-upon guidelines and indicators. Education for healthcare professionals on ASPs should start in universities and continue post qualification. Community advocacy on the rational use of antibiotics should also include social media activities to dispel misinformation. Conclusion: The quality of current prescribing of antibiotics in ambulatory care is sub-optimal in Tanzania. This urgently needs to be addressed
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