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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Teacher preparedness in dealing with learners' social problems

Abbas, Faheema January 2008 (has links)
Dissertation (Master of Education( Education))--Cape Peninsula University of Technology, 2008 / The purpose of the study was to investigate how teachers dealt with learners’ social problems. Another concern of the study was to investigate the extent to which pre-service and in-service teacher-training prepared teachers to deal with learners’ social problems. The research used qualitative methodology. The major advantage of using qualitative research was that it focused on researching teachers in their school setting, to determine how teachers dealt with learners’ social problems. The main instrument used was interviews as it yielded rich in-depth knowledge and allowed me to probe responses and investigate the teachers’ feelings and emotions. A purposive sampling technique was used to select the respondents. The study population was confined to four public high schools in Cape Town. It was composed of three newly qualified teachers and one experienced teacher. The results reflected that teachers dealt with learners’ social problems by trial and error and there was no evidence of deliberate planning in identifying learners with social problems. The preservice teacher training programmes did not equip teachers with the skills to deal with learners’ social problems. Although teachers received some form of training at schools, the training was not effective in assisting them. The thesis argues that social problems cannot be dealt with solely by the school or the teacher. It is recommended that the Department of Education, the community and the parents, as well as other social service organisations, should jointly create preventive and intervention strategies to assist learners with social problems. Such a holistic approach, the study asserts, could assist schools and teachers to deal with learners’ social problems more effectively. Teachers should receive pre-service training to deal with learners’ social problems, for example, by adding a module such as Sociology of Education. The teachertraining programmes and continuous in-service training programmes should ensure that teachers are exposed to current Departmental policies and documents that can assist them in dealing with learners’ social problems.
2

An investigation into the perceptions of Grade 7 learners of the effectiveness of a guided reading programme

Kohler, Valerie January 2008 (has links)
A minor dissertation submitted in partial fulfillment of the requirements for the degree of Masters in Education Presented to the Faculty of Education and Social Sciences, CAPE PENINSULA UNIVERSITY OF TECHNOLOGY, 2008 / Reading is a critical tool for the mastery of all learning areas and is one of the best predictors of long term learning achievement. Reading must be considered a priority area in efforts to improve the quality of basic education, particularly for learners from disadvantaged backgrounds. Many learners in South Africa come from a largely oral culture in which reading of books is not common and many come from disadvantaged communities that cannot afford to buy books. The provincial and national systemic evaluation results (2003, 2005) for reading showed that at least 40% of Grade 3 and 6 learners were reading below grade level. In January 2005, in the present study, 50 % of the Grade 7 learners were reading below Grade 7 level. Many learners were discouraged because they could not master the reading tasks set to them. Others responded to the task with boredom and disdain. The learners who could read seem to be the only ones who were enthusiastic about starting and completing the reading tasks. By the end of the year, after using a guided reading programme, all students had developed a love for reading and many were reading on Grade 7 level. The present empirical study is grounded in the social constructivist framework, originating from the works of Piaget (1978), Vygostky (1929) and Cambourne (2004). Their foundational principals together with the learning outcomes specified in the Revised National Curriculum Statement (2002) formed the basis of this literacy study. A questionnaire was administered to forty-four learners at the end of a complete year where I had used the guided reading programme. The questionnaire consisted of ten closed questions and six open-ended questions. The results were analysed both quantitatively and qualitatively. The results of this study showed that the learners responded positively to reading in groups, that learners developed an interest in reading, that they acquired reading skills that they needed to become independent readers, all of which ultimately improved their self esteem and self confidence.
3

Non-Newtonian loss coefficients for Saunders diaphragm valves

Kabwe, Aime Mume January 2009 (has links)
Dissertation submitted in fulfilment of requirements for the degree Master Technology: Chemical Engineering in the FACULTY OF ENGINEERING at the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY, 2009 / The prediction of the energy losses when designing pipeline and pumping systems requires accurate loss coefficient data. But the loss coefficient data found in the open literature was not adequate for predicting the loss coefficient for Saunders straight-through diaphragm valves. As more accurate loss coefficient data to enable more efficient pipeline designs are scarce in the open literature, it is problematic to predict the head loss due to the pipeline fittings, and particularly for diaphragm valves. Most of the data given in the literature are for turbulent flow based on water. Due to water shortages mining operations are forced to increase their solids concentrations and to operate in laminar flow (Slatter, 2002). Consequently there is a need to determine loss coefficient data in laminar flow for valves used in these industries to ensure energy efficient designs (Pienaar et al., 2001; 2004) or if needed, to derive a new correlation to predict losses through Saunders diaphragm valves. However, a systematic study of various sizes of diaphragm valves of different manufacturers to ascertain, if the same loss coefficient can be applied, has never been done. Therefore a comparison will be made between the data produced in this work and the existing correlations. The objective of this research was to determine loss coefficient data in laminar, transitional and turbulent flow for the Saunders type straight-through diaphragm valves ranging from 40 mm to 100 mm in the fully open, 75 %, 50 % and 25 % open positions, using a range of Newtonian and non-Newtonian fluids. The test work was conducted on the valve test rig in the Flow Process Research Centre at the Cape Peninsula University of Technology. This work investigated only Newtonian and time independent homogeneous non-Newtonian fluids or slurries flowing through Saunders straight-through diaphragm valves in the turbulent, transitional and laminar regimes. Weir-type Saunders valves and time-dependent fluid behaviour were not investigated in this study. Preamble Non-Newtonian Loss Coefficients for Saunders Diaphragm Valves A Mume Kabwe The results for each test are presented in the form of valve loss coefficient (kvalve) against Reynolds number (Re). This thesis adds new loss coefficient data to the open literature, and a new correlation, which will be useful for designing pipelines in industries, as well as contributing to the academic debate in this discipline.
4

A quality management system (QMS) for a radiation oncology department in an academic hospital in the Western Cape, South Africa

Higgins, Helena Johanna January 2012 (has links)
Thesis submitted in fulfilment of the requirements for the degree: Master of Technology: Radiography (Therapy) Faculty of Health and Wellness Sciences Cape Peninsula University of Technology, 2012 / The focus of this study is to investigate the level at which quality management (QM) objectives, according to ISO standards, are met by the radiation oncology staff as well as doctors referring patients and patients receiving treatment at an oncology department. The study was undertaken at an academic hospital in the Western Cape, South Africa. The study addressed the following research question: “Do the QM system and practices at the division of Radiation Oncology at an academic hospital comply with ISO standards?” Radiation therapy is the treatment of cancer with ionizing radiation. The department has Quality Assurance (QA) practices that assure the safe, consistent delivery of radiation to the target volumes that are defined for treatment from a technical point of view. Errors or incidents are inevitable and an understanding of when, why and how they occur could assure that systems are put into place to help minimize the frequency with which they occur. In order to do this, a systematically planned programme should be documented and implemented to assure that the treatment delivered meets the required standards. Such a programme is called a Quality Management System (QMS) and it must involve the documentation of all the processes that could influence or is involved in the treatment of patients. This includes the managerial, the psycho-social as well as the technical treatment planning processes. An important process is the identification of the QM objectives. Furthermore, the current levels of satisfaction with the QM programme needs to be assessed in order to improve the QMS. The approach of the study is twofold. Firstly, the ISO standards regarding the first three QM objectives were identified and documented from literature and documents. The three QM objectives identified were: i) staff satisfaction and morale, ii) referring doctor satisfaction and iii) patient satisfaction. Secondly, the existing QM practices were investigated by means of an organisational satisfaction survey audit conducted with the staff in the department, the doctors referring patients to the department and the patients getting treatment at the department. The staff members were represented by a self-selecting sample group of 44 participants that completed a self-administered survey questionnaire. The referring doctors were also a self-selecting sample group of 64 participants that received a mailed or hand-delivered survey questionnaire. The patient group was a statistically calculated proportion sample of 230 patients that were interviewed with a structured administered survey questionnaire by the researcher. The analysis of the data was layered and triangulated by means of identification of perspectives from different groups of people involved in the same setting. The first layer of analysis involved deconstructing and discussing the ISO documents, guidelines and policies in order to establish the required ISO standards regarding the three QM objectives researched in this study. The second layer of analysis involved quantitative descriptive analysis methods used to analyse the data generated by the Likert-scale questions. The third layer of analysis involved the analysis of the narrative data from the open questions of the questionaires and structured interviews with the patients where content thematic analysis allowed categories to emerge by means of pattern matching. A benchmark of 50% was established from literature for satisfaction levels to be considered acceptable. The findings of this study are expressed in terms of meeting this benchmark. In the staff group, five quality indicators were investigated. Three out of the five indicators of staff satisfaction (60%) met the 50% benchmark, which indicates that the department is meeting the standards set for this QM objective. The three indicators that met the benchmark were: i) working environment, ii) physical environment and safety and iii) job description. The two indicators not meeting the benchmark were i) recognition and ii) re-imbursement. In the referring doctor group a total of three quality indicators were investigated and two (66%) met the benchmark. The two indicators that met the benchmark were i) telephone etiquette and ii) patient management. The indicator not meeting the benchmark was follow-up reports. Therefore, the quality indicators for this specific QM objective are also meeting the standard required. The results for the last QM objective, patient satisfaction, shows that the seven indicators investigated have all (100%) met the benchmark set for satisfaction. The seven quality indicators investigated were i) administration, ii) atmosphere and comfort, iii) cleanliness of the department, iv) professionalism, v) information sharing, vi) cleanliness and safety in the ward and vii) patients’ general comfort in the ward. The content analysis resulted in recommendations that were categorised as follows: i) specific recommendations according to the thematic content, ii) practical recommendations for future audits and iii) recommendations regarding the proposed QMS for the department. An important outcome of this study was the establishment of baseline data regarding these three QM objectives and the development of shortened survey questionnaires for use in future organisational survey audits. In conclusion, it is argued that quality improvement should be seen as a continuous, structured process using a system that can create participation throughout the department to plan and implement processes that would meet and exceed the expectations and demands of the clients and staff utilizing the services of the department. This process, together with the structure provided by the ISO 9000 set of standards, is a valuable guideline for the development of a comprehensive QMS. This thesis was an initial step towards a scientifically documented, implemented and regulated QMS that could guide the department in working towards achieving their set objectives and eventually towards attaining Radiation Therapy specific accreditation.
5

Die invloed van teken op die ontwikkeling van skryfvaardighehe van Graad R-leerders in 'n landelike multigraadskool

van der Merwe, Rene January 2012 (has links)
Die tesis is voorgelê ter verwerwing van die graad: Magister in Opvoedkunde aan die KAAPSE SKIEREILAND UNIVERSITEIT VAN TEGNOLOGIE Fakulteit Onderwys en Sosiale Wetenskappe, 2012 / The aim of the research was to examine the development of writing skills through drawing in order to identify skills and strategies needed by grade R learners of a rural multi-grade school for motor development and invented writing. Appropriate teaching was researched according to which an intervention programme was developed, applied and evaluated. Literature was examined to establish what is already being taught in this development phase and context. When drawing, children not only go through the same universal development stages and inherent biological processes, but their mark-making has meaning regarding communication and writing. During the drawing process children develop control of large and small motor muscle groups. Through daily drawing activities on different levels through interesting presentation these muscle groups are developed, skills mastered and concentration on the learning process improved. When, however, children come from a home context where a stimulating milieu of learning is lacking, it leads, not only to weak sosio-emotional and cognitive development, but can also be linked to weak health and physical growth, which includes large and small motor skills. These large and small motor skills are required for the development of writing skills which in turn are required for future formal teaching. The following questions were answered: Which characteristics of drawing are important in writing skills? What appropriate teaching is necessary for drawing and writing competence? How are teaching of drawing and writing skills currently applied in grade R classes in multi-grade schools? Of what components should an intervention programme consist so that grade R learners of a multi-grade school can benefit with regard to writing skills? What requirements must the intervention programme for this special group meet to implement drawing and writing skills in a sustainable way? Design based research was used as methodology. A literature study was done during the preliminary phase and an intervention programme was designed. During the prototype phase the intervention programme was implemented and honed by repeated design cycles. Assessment showed that the intervention met the preconceived specifications by achieving remarkable results in respect of the general poise, action of drawing, position of drawing, posture, dominance and grip. The development levels of the children were increased by daily drawing accompanied by conversation and writing modelling. During the three phases data was collected in the following ways: informal conversations with the teacher; a semi-structured interview with the teacher; check-lists; a pre and post test; participatory observation; artefacts (children’s art); video recordings and field-notes. A needs analyses and expert appraisal were used as strategies. To be able to write is a basic skill, and without it the future prospects of the children are seriously hampered. Early stimulation and exposure to drawing media and instruments, the manipulation thereof and the development of large and small motor skills to enhance writing skills, therefore play a decisive role in the optimal development of the children. When children have the ability to write it leads to a future of opportunities for schooled and highly schooled labour which in turn contributes to the economic stability of the country.
6

An analysis of industry relevance of acquired project management skills within a University of Technology

Eigelaar, Andries J January 2012 (has links)
Master of Technology Business Administration in Project Management in the Faculty of Business at the Cape Peninsula University of Technology, 2012 / The purpose of this study is to investigate the understanding and awareness of Project Management graduates regarding the soft and hard skills of Project Management, specifically the application of these skills in the successful outcome of projects. The research participants for this study were BTech Project Management graduates from CPUT. This study investigates the perceptions of the critical cross-field outcomes of the BTech Project Management programme in association with the Project Management Body of Knowledge (PMBOK) with regard to hard and soft skills. As Project Management continues to grow as a discipline; it is becoming more evident that success of the role of project managers cannot be attained with technical skills only. Hard skills are being recognized as one of the minimal requirements for a project manager. A need for excellent interpersonal or soft skills are necessary conditions for success, and although some would disagree, others advocate that these are skills that can be taught and learned rather than skills that are innate or genetic. Considerable effort has been made in the area of hard skills processes, tools and techniques. Project Management methodologies are being developed and improved, but still a large number of projects do not deliver. Apart from hard skills, research in the area of soft skills is promising. A range of soft skills attributes required by project managers has been acknowledged. Good Project Management requires not only knowledge of and the ability to apply technical or “science” skills, but also the softer “art” skills, which include human behaviour and interactions. Applying the right balance or mix of art and science, which will vary for different projects, is key to successful Project Management.
7

Development of a power distribution module for a nanosatellite

Maleka, Motlokwe January 2013 (has links)
Thesis submitted in partial fulfilment of the requirements for the degree Magister Technologiae: Electrical Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology 2013 / The space environment is characterised by harsh radiation, extreme temperatures and vacuum. Electronics subsystems for satellite applications are designed to be fault tolerant and robust enough to survive this environment. A power distribution module (PDM) for a CubeSat nanosatellite application is developed here, with the aim to distribute power to CubeSat subsystems reliably. The PDM prototype is carefully designed with reference to an extensive literature study. The study dwells on the low Earth orbit (LEO) space environment, critically identifying radiation sources and temperature ranges in the LEO. The study further investigates traditional analogue techniques of logic circuit design using bipolar junction transistors (BJTs) which are known for their higher tolerance to radiation sources as compared to recent integrated circuits (ICs). Careful consideration is given to different ways of designing a fault tolerant system. The study specifically looks at redundant circuit design within the limitations of weight and space of a nanosatellite. Possible electrical faults in power systems are identified, which include over-currents, over-voltages, over-temperatures, inrush currents and latchup. This study shows that identified faults generally are overcurrents. A power switch is included in each power distribution channel to trip the current in case a faulty condition is detected. The PDM is designed to have eight power output distribution channels to allow a subsystem load to connect to more than one channel, thereby meeting its power requirements. The PDM power channels are designed identically. Upon application, current limits are selected by a two-resistor divider circuit and connectors are used to connect to a required voltage bus at manufacturing time. The system’s functionality is tested and verified using an Arduino development board interfaced to all I2C devices as a master node, typically the on-board computer (OBC) in a real satellite mission. The system’s functionality in a Gamma irradiated laboratory environment is verified to perform as required. The PDM system is further tested in a temperature cycled chamber from -31°C to 61°C. The system survived the entire eight hour test duration of two cycles. It is observed that the system is fault tolerant to radiation sources up to 10 krad and the temperature limits mentioned. The PDM system is recommended as an additional module to the CubeSat electrical power subsystem (EPS), thereby improving the reliability of the power subsystem. Keywords: CubeSat, power channel, module, radiation, reliability, efficiency, I2C, prototype.
8

Reduction of ammonia from wastewater effluent using modified activated clay

Ilunga, Wighens Ngoie January 2013 (has links)
Thesis submitted in partial fulfilment of the requirement for the degree of Master of Technology: Chemical Engineering at the Cape Peninsula University of Technology, 2013 / It has been noticed that effluent from wastewater treatment plants in South Africa does not comply with the minimum requirements of environmental standards of wastewater effluent for discharge into the environment. This is due to the presence of soluble, persistent organic pollutants (POPs) and other related pollutants, in particular ammonia (PakWaterCare Services, 2011). To rectify this situation, this study sought to treat wastewater effluents, initially using natural clay (bentonite and Montmorillonite). Secondly, the clay was activated by sulphuric acid to increase its adsorptive properties. The concentration of sulphuric acid ranged from 0.5M to 18.4M so that the effective concentration could be reached. Tests were carried out to evaluate the dosages and conditions (mixing and flocculation stirring speeds, durations, and settling times) required to achieve optimum POPs capture. The experiment was conducted two ways: 1) at first the only bentonite was used, and 2) samples were subsequently activated with H2SO4 (6M; 8M and 11M). The dosage of the coagulant into the jar tester beakers per litres of water was 0.5; 1; 1.5; 3; 5 and 10g. And then, by keeping the mixing speed (rapid mixing at 150rpm for 1min and slow mixing at 20rpm for 20min) and settling time constant (30min), the bentonite and Montmorillonite were activated by H2SO4 (0.5M; 3M; 5M; 11M and 18.4M). It was observed that for an increase in coagulant dosage, a decrease in pH was observed. This was due to an increase in acid dosage which influences the acidity of the water. The achieved results for wastewater effluents indicated that using activated clay (bentonite) as a coagulant with an optimum removal and maximum surface area for acid activation attained at 5M concentration of sulphuric acid used for activation of clay. The combinations of 5M bentonite clay to ZINPs (zero valent iron nano particles), in a mass ratio of 99:1 respectively, reduced ammonia up to 96.85% with a dosage of 61.6mg coagulant, a reduction from the raw water 277mg/L to 8.71mg/L. Most of the sample pH ranged from 6.5 to 9 as required by the Department of Water Affairs and Forestry. The samples’ conductivities were below the standard 2500μs/cm; the 5M+ZVINPs at 60.1mg had a conductivity of 259μs/cm. Hence, this treatment is not only effective and economical, but also ecologically acceptable.
9

Sorption and solubility of a denture base acrylic

Latief, Abduraghman January 2012 (has links)
Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Dental Technology in the Faculty of Health and Wellness Sciences at the Cape Peninsula University of Technology, 2012 / Statement of problem It is well documented that water sorption and water solubility by auto-polymerizing resins have a negative impact on their physical properties and may lead to harmful tissue reactions. The presence of residual monomer is often identified as the main cause for adverse tissue reactions. To optimize the polymerization reaction, the use of the proper powder/liquid ratio is recommended in the fabrication of a dental appliance. It is also recommended that a dental appliance should be soaked in water for at least 24 hours before delivery to a patient, in order to reduce the possible adverse effect. For auto-polymerizing resins, associated with higher residual monomer levels than heat-cured resins, soaking the appliance at elevated temperatures (65ºC for 60 minutes), would reduce the residual monomer content more efficiently than at room temperature. This requires additional processing conditions from the technician or dentist. Changing the powder/liquid ratios, deliberately or not, may modify the residual monomer content of the final product. A relationship exists between the levels of residual monomer and water sorption. Also, residual monomer leaching into the oral fluids may lead to adverse effects such as, oral tissue irritation or a delayed hypersensitivity reaction. Aim of the study The aim of this study was to evaluate the effect of different powder/liquid ratios and different water temperatures on the levels of sorption and solubility of an auto-polymerizing resin material used for denture bases. The null-hypothesis tested was that there is no difference in sorption and solubility among groups of specimens made from an auto-polymerizing resin material soaked in water at different temperatures and/or fabricated with different powder/liquid ratios. Material and methods Specimens were made from cold-cure pour-type denture base resin (Type 2, Class 2) using different powder/liquid ratios and soaked at different soaking temperatures. One group of specimens fabricated with the manufacturer’s recommended powder/liquid ratio and soaked in water at 37ºC, served as the control group for both experiments. Custom-made stainless steel moulds were used to fabricate resin disks, with a diameter of 50mm and a thickness of 0.5mm. For the temperature-controlled experiment, identical specimens were prepared and stored in distilled water at 37ºC; 45ºC; 55ºC and 67ºC. For the ratio-controlled experiment, the ratios were increased incrementally for each group, starting with a 10% increase, followed by a 15%; 20% and 25% increase in monomer. Water sorption and solubility were tested in accordance with ISO Standard 1567 (1999). Specimens were weighed before and after water immersion, and desiccation. Water sorption and solubility were calculated using the difference in wet and dry mass and the volume of the specimens. The water sorption and solubility results were analyzed by means of analysis of variance. For multiple comparisons, Bonferroni simultaneous confidence intervals (α=0.05) were applied. Results For the ratio-controlled experiment, water sorption mean values varied from 24.148 μg/mm3 to 25.1333 μg/mm3. Statistically significant differences in mean values were found between the following groups: 0%-10%; 0%-15%; 0%-25%; 10%-20%; 15%-20% and 20%-25% ratio groups (P<.0001). Water solubility mean values varied from 0.616μg/mm3 to 0.932μg/mm3. Statistically significant differences in mean values were found between the following groups: 0%-15%; 0%-20%; 0%-25% and 10%-25% and 20%-25% ratio groups (P<.0001). For the temperature-controlled experiment, water sorption mean values varied from 24.185μg/mm3 to 26.434μg/mm3. Statistically significant differences in mean values were found between the following groups: 37ºC-45ºC; 37ºC-55ºC; 37ºC-67ºC; 45ºC-67ºC and 55ºC-67ºC temperature-controlled experiments (P<.0001). Water solubility mean values, for the same experimental groups, varied from 0.616μg/mm3 to 2.752μg/mm3. Statistically significant differences in mean values were found among all the 6 pairs of groups (P<.0001). Despite statistical differences, the water sorption and water solubility values of the tested resin for both experiments and all groups were within the ISO Standard 1567 (1999) specification limits. Conclusion For the ratio-controlled experiment, there was an inverse relationship between the mean sorption and solubility values with an increase in liquid in the mixture: low water sorption levels are associated with high solubility levels. The lower water sorption and higher solubility results for more fluid mixtures could be related to initial and residual high monomer content characteristic of auto-polymerizing materials. These higher levels of free monomer are consequently released upon immersion in water; hence the higher water solubility levels. For the temperature-controlled experiment, a higher soaking temperature resulted in an increase in water solubility levels. The higher solubility levels could be attributed to the higher soaking temperatures causing higher or faster monomer diffusion from the resin material. Except for the 67ºC group, sorption is also lower with higher temperatures. It may be assumed that an additional polymerization process takes place and a subsequent more inaccessible polymer matrix is produced. For the 67ºC group, thermal expansion may explain the higher sorption level. Clinical Implications In terms of the sorption and solubility results, this auto-polymerizing pour-type resin may be used as a denture base resin. Even though statistical differences were demonstrated, the material satisfies the ISO 1567 (1999) requirements not only for auto-polymerizing but also for heat-polymerizing resins. Therefore, within limits, the mixture may be prepared more fluidly in order to improve flow of the material, without negatively affecting its sorption and solubility properties. Because solubility is higher at higher soaking temperatures, this property can be used to minimize monomer content of the appliance. Therefore, it is recommended that the dental appliance be soaked in warm water, below 67ºC, prior to delivery to the patient.
10

Reference values for thyroid uptake of technetium-99m pertechnetate for the Namibian population

Hamunyela, Roswita Hambeleleni January 2012 (has links)
Dissertation submitted in fulfilment of the requirements for the degree Master of Technology: Radiography (Nuclear Medicine) In the Faculty of Health and Wellness Sciences At the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY, 2012 / Thyroid physiology and structure can be evaluated by scintigraphic imaging. Iodine-131, discovered in the late thirties was the first radioisotope to be used for thyroid uptake assessment, since then thyroid uptake and imaging continues to play a vital role in different thyroid related clinical situations. Because Iodine-131 has serious disadvantages related to high radiation dose, it has been limited to staging and follow up of patients with thyroid carcinomas. Its substitute Iodine -123 has proved to be suitable in terms of shorter half-life and better imaging energy. Technetium-99m pertechnetate, because of its availability is also used for thyroid imaging and uptake assessment. The similarity of the Technetium-99m pertechnetate ions and iodide is the explanation for the thyroid glands ability to absorb it. Historically, chronological changes in the normal values of thyroid uptake normal values have been reported in different geographical areas. These changes have been linked to geographical and chronological fluctuations in dietary iodine intake in different populations. Technetium-99m pertechnetate, Iodine-131 and Iodine-123, all reflect thyroid iodide accumulation. In areas where there is iodine deprivation there will be elevated radioisotope uptake in euthyroid persons, and radiotracer uptake is even higher in areas of Iodine deficiency. Conversely in areas where a population is exposed to stable iodine and abundant amount of iodine intake from other sources, radiotracer uptake will be decreased. Namibia is a country with mixed ethnicity consisting mainly of Africans (Hereros, Ovahimba, Kavangos, Caprivians, Ovambo, Damaras, Namas, Bushmen, Coloureds and Caucasians). The population has access to dietary iodine and all ethnic groups consume reasonable amounts of food containing iodine such as bread, dairy products, table salt and sea food. Similar to other Nuclear Medicine departments worldwide, Namibia makes use of Technetium-99m pertechnetate for thyroid uptake and imaging. However thyroid uptake quantification needs to be related to normal values as a point of reference. Despite reports of thyroid uptake fluctuations of normal values and reports emphasising the importance of periodic checks on the thyroid uptake normal values, Namibia has never determined these reference values. This study examines the fundamental statement posed in the hypothesis that the thyroid uptake reference values for Technetium-99m pertechnetate in a Namibian population deviate from available International normal reference values. Eighty three participants considered to be euthyroid from Windhoek, Namibia received Technetium-99 m pertechnetate as part of their evaluation. The euthyroid state was based on a combined evaluation of clinical history, palpation of the thyroid gland and assessment of thyroid hormones (TSH, T3 and T4). The objectives of the study were:  To establish normal reference values of Technetium-99m pertechnetate uptake in euthyroid persons in Namibia.  To compare the outcome reference values to current available existing International normal reference values.  To determine possible factors contributing to the deviation of thyroid uptake reference values in the Namibian population.  To recommend reference values for Namibia. This was achieved by studying the unmedicated 83 participants with their iodine diet, rather than patients with thyroid or other diseases. The participants reported to the Nuclear Medicine department. The participants completed a questionnaire designed to reveal the presence of thyroid pathologies or any other pathology. The completed questionnaire was reviewed and if the participant fulfilled the requirements for the study, blood was drawn for thyroid hormone assessment. The participants were then given 100MBq Technetium-99m pertechnetate intravenously. Using a low energy high resolution dual head gamma camera, the thyroid uptake was recorded at 20 minutes. There was a marked difference between the International normal values (0.75% to 4%) used in the Nuclear Medicine department and those found in this study. The results of seven subjects were excluded due to abnormal blood results, and technical errors, bringing the actual sample size to 76 euthyroid participants. The age range was 39 to 81 years, and there were 58 females and 18 males. The mean uptake for the euthyroid group was found to be 0.78%± 0.45%. The Kolmogorov-SmirnovaLilliefors Significance parametric test presented us with results that state that our population has a non-normal distribution, and therefore the standard deviation should not be applied to determine the normal values. The statistical test for skewness and kurtosis was adopted in this study to correct for skewness and the normal values determined were 0.35% to 1.22% (95.5% CI) of Technetium-99m pertechnetate at 20 minutes. An alternative method used to determine the normal reference range for Technetium-99m pertechnetate in a study sample obtained from a non- normal distribution was determined using the 5th and the 95th percentiles .The normal reference range using the 5th and the 95th percentile was 0.17% - 1.7%. This study provides new evidence supporting the importance of periodic checks on normal reference values. The evidence is provided by the analysis of the empirical data obtained in this study of a population that has sufficient daily intake of stable iodine. The results obtained from this study and other studies proving the difference in thyroid uptake between different populations and geographical regions makes it incumbent upon laboratories to establish a normal reference range for a particular geographical location. Furthermore the study attests to the importance of re-evaluating normal values for thyroid uptake as part of a quality assurance programme.

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