Magister Artium (Psychology) - MA(Psych) / In the majority of the schools in South Africa (SA), learners commence education in English. This English milieu poses a considerable challenge for English second-language speakers. In an attempt to bridge the gap between English as the main medium of instruction and the nine indigenous languages of the country and assist with the implementation of mother-tongue based bilingual education, this study focuses on the cross-validation of a monolingual English test used in the assessment of multilingual or bilingual learners in the South African context.

Introduction Radiologic Technologists exposed to continuous low dose radiation may have an increased risk for spontaneous abortions. Although the federally mandated radiation dose limit to the developing fetus of an occupational worker is 5mSv, well below the documented threshold of 100mSv, some studies have suggested an increased risk for spontaneous abortions in occupationally exposed females. The effects of exposure to low levels of radiation are difficult to discern from the usual occurrence and are limited in the literature because of the large sample size needed to achieve statistical power. This study contains data from 152,439 self-reported pregnancies and possesses the appropriate sample size to assess the risk of spontaneous abortions incident to radiologic technologists who maintain fetal radiation dose levels within federal guidelines. Methods This non-experimental retrospective designed study uses data from the United States Radiologic Technologist Study (USRTS). The USRTS began in 1982 as a joint effort between the American Registry of Radiologic Technologists (ARRT),UniversityofMinnesotaand the National Cancer Institute to study the radiation effects from low-dose occupational exposure. This longitudinal study follows more than 90,000 current and former technologists through periodic surveys and contains a sufficient sample size to overcome statistical power concerns. The provided data included the order and outcome of each self-reported pregnancy as well as the year of each live birth. The data were therefore manipulated to provide a likely gestational interval for both a reported live birth and spontaneous abortion. After calculating the spontaneous abortion rate for the final sample, a binary logistic regression was performed to determine if levels of estimated fetal radiation dose are associated with predicting the odds of a reported spontaneous abortion. A linear regression analysis was then performed to assess the relationship between the calculated odds ratios of a reported spontaneous abortion as a function of estimated fetal radiation dose, specifically to determine the significance of the linear relationship Results The overall spontaneous abortion incidence to the cohort reporting at least one live birth or spontaneous abortion was 14.8%, lower than the reported national incidence of 15-20%. Using up to 1mSv as the reference fetal radiation dose category, the odds ratios of a spontaneous abortion for 1-2mSv, 2-3mSv, 3-4mSv and 4-5mSv were calculated as 1.57, 1.82, 2.11 and 2.15 respectively. This increase in odds was linear with estimated fetal radiation dose as demonstrated by the significant regression equation (F=29.93, p = .01) and an R2 of 0.9089. Conclusions By demonstrating an increased risk at levels of radiation as low as natural background, and further demonstrating the risk increases linearly with radiation dose, the Linear Non-Threshold Theory appears to be the more likely risk model for predicting spontaneous abortions in lieu of the belief that a 100mSv threshold must first be exceeded for a radiation induced spontaneous abortion to occur. Application of this model demonstrates the risk of a spontaneous abortion is twice as likely in occupational workers whose fetal radiation doses are closer to the maximum allowable limit of 5mSv compared with those who maintain fetal radiation doses below 1mSv.

Magister Artium - MA / In the majority of the schools in South Africa (SA), learners commence education in English. This English milieu poses a considerable challenge for English second-language speakers. In an attempt to bridge the gap between English as the main medium of instruction and the nine indigenous languages of the country and assist with the implementation of mother-tongue based bilingual education, this study focuses on the cross-validation of a monolingual English test used in the assessment of multilingual or bilingual learners in the South African context. This test, namely the Woodcock Muñoz Language Survey (WMLS), is extensively used in the United States in Additive Bilingual Education in the country. The present study is a substudy of a broader study, in which the original WMLS (American-English version) was adapted into SA English and Xhosa. For this specific sub-study, the researcher was interested in investigating the scalar equivalence of the adapted English version of the Verbal Analogies (VA) subscale of the WMLS across English first-language speakers and Xhosa first-language speakers. This was achieved by utilising differential item functioning (DIF) and construct bias statistical techniques. The Mantel-Haenszel DIF detection method was employed to detect DIF, while construct equivalence was examined by means of exploratory factor analysis (EFA) utilising an a priori two-factor structure. The Tucker's phi coefficient was used to assess the congruence of the construct across the two language groups / South Africa

The Swedish death rate related to narcotics is amongst the highest within the EU. The purpose of this study is to use process tracing while investigating and understanding the high death rate among people who use narcotics in Sweden. The focus is on whether the Swedish drug policy is driven by morals instead of scientific proof and asks whether morals are the main cause of the high death rate in Sweden. The study utilizes the “threshold theory” and the theory of “symbolic politics.” To do this the following questions are being answered: “How has the Swedish zero tolerance towards narcotics looked like since the 1970s until present day?” and “are there any signs to proof that the Swedish drug policy is driven more by morals than by scientific evidence, and if so, what are they?” The study also tests the hypothesis that the high death rate is related to the restrictive drug policy in Sweden. In order to answer this the study collects data and regulations from different time periods in Sweden thru a qualitative method. The study confirms that the Swedish drug policy is driven by moral while overlooking scientific proof and it is also likely that the hypothesis of the study is true.

Radiation from Computed Tomography (CT) is now the major contributor to population radiation dose. Despite controversy around the dose-effect relationship of radiation from CT, the linear non-threshold (LNT) theory is endorsed by many authorities, and constitutes the basis of cancer risk estimates. The purpose of this study was (1) a literature review of radiobiological theories, and methods of dose saving stategies in CT; (2) to highlight the importance of dose saving in CT, and to demonstrate how dose can be saved in a radiology department: Following a 40% reduction in reference X-ray tube current for a CT of the urinary tract, the effecitve dose and estimated lifetime attributable risk of incident cancer due to this CT in a group (n=103) were reduced by 37% and 38% in an age and sex-matched group respectively. The literature review showed that the public health implications of CT radiation exposure remain uncertain. / Health Studies / M.A. (Public Health)

<p>In the majority of the schools in South Africa (SA), learners commence education in English. This English milieu poses a considerable challenge for English second-language speakers. In an attempt to bridge the gap between English as the main medium of instruction and the nine indigenous languages of the country and assist with the implementation of mother-tongue based bilingual education, this study focuses on the cross-validation of a monolingual English test used in the assessment of multilingual or bilingual learners in the South African context. This test, namely the Woodcock Mu&ntilde / oz Language Survey (WMLS), is extensively used in the United States in Additive Bilingual Education in the country. The present study is a substudy of a broader study, in which the original WMLS (American-English version) was adapted into SA English and Xhosa. For this specific sub-study, the researcher was interested in investigating the scalar equivalence of the adapted English version of the Verbal Analogies (VA) subscale of the WMLS across English first-language speakers and Xhosa first-language speakers. This was achieved by utilising differential item functioning (DIF) and construct bias statistical techniques. The Mantel-Haenszel DIF detection method was employed to detect DIF, while construct equivalence was examined by means of exploratory factor analysis (EFA) utilising an a priori two-factor structure. The Tucker&rsquo / s phi coefficient was used to assess the congruence of the construct across the two language groups</p>

<p>In the majority of the schools in South Africa (SA), learners commence education in English. This English milieu poses a considerable challenge for English second-language speakers. In an attempt to bridge the gap between English as the main medium of instruction and the nine indigenous languages of the country and assist with the implementation of mother-tongue based bilingual education, this study focuses on the cross-validation of a monolingual English test used in the assessment of multilingual or bilingual learners in the South African context. This test, namely the Woodcock Mu&ntilde / oz Language Survey (WMLS), is extensively used in the United States in Additive Bilingual Education in the country. The present study is a substudy of a broader study, in which the original WMLS (American-English version) was adapted into SA English and Xhosa. For this specific sub-study, the researcher was interested in investigating the scalar equivalence of the adapted English version of the Verbal Analogies (VA) subscale of the WMLS across English first-language speakers and Xhosa first-language speakers. This was achieved by utilising differential item functioning (DIF) and construct bias statistical techniques. The Mantel-Haenszel DIF detection method was employed to detect DIF, while construct equivalence was examined by means of exploratory factor analysis (EFA) utilising an a priori two-factor structure. The Tucker&rsquo / s phi coefficient was used to assess the congruence of the construct across the two language groups</p>

Radiation from Computed Tomography (CT) is now the major contributor to population radiation dose. Despite controversy around the dose-effect relationship of radiation from CT, the linear non-threshold (LNT) theory is endorsed by many authorities, and constitutes the basis of cancer risk estimates. The purpose of this study was (1) a literature review of radiobiological theories, and methods of dose saving stategies in CT; (2) to highlight the importance of dose saving in CT, and to demonstrate how dose can be saved in a radiology department: Following a 40% reduction in reference X-ray tube current for a CT of the urinary tract, the effecitve dose and estimated lifetime attributable risk of incident cancer due to this CT in a group (n=103) were reduced by 37% and 38% in an age and sex-matched group respectively. The literature review showed that the public health implications of CT radiation exposure remain uncertain. / Health Studies / M.A. (Public Health)