1,721,008 research outputs found
Dietary fat modulates the relationship between polymorphisms in the TNFA and IL-6 genes, and obesity and serum lipid concentrations in black and white South Afican women
No full textIncludes abstract.Includes bibliographical references.The primary aim of the thesis was to investigate associations between TNFA (TNFA-308 G>A and -238 G>A) and IL-6 (-174 G>C, IVS3+281 G>T, IVS4+869 A>G) sequence variants and obesity and serum lipid concentrations in black and white SA women. This included identifying sequence variants in the IL-6 gene with a reported high heterozygosity in both the white and black SA populations (rs1554606 and sr2069845). Dietary intake data of adequate reporters was then included in the analysis to investigate whether dietary fatty acid intake modulated the interactions between the TNFA and IL-6 SNPs (TNFA -308 G>A and -238 G>A & IL-6 -174 G>C, IVS3+281 G>T, IVS4+869 A>G) and obesity, measures of adiposity and serum lipid concentrations, and whether interactions identified differed between black and white women
A psycho-educational programme for grade 10 learners to facilitate a positive experience of physical science
Get PDFM.Ed.The goal of this research study was to provide psycho-educational guidelines that will facilitate a positive experience of physical science for grade 10 learners. The stakeholders in this research study were grade 10 physical science learners and grade 10 physical science educators. A positive experience of physical science is important for various reasons. One reason is that there is a declining interest in learners pursuing scientific careers (Lepkowska, 1996:33). The main reason for this is that learners do not feel they are able to master the subject. They often do not understand what they are being taught in class and how it is applicable to their lives. Learners therefore experience a “love/hate” relationship with the subject – when they do well in the subject they like it and when they achieve poorly, they hate it. This complex relationship is often misunderstood by physical science educators. Educators often do not realise how they can change learners’ experience of the subject. It was one of the main aims of this research study to provide educators with practical guidelines on how to facilitate a positive experience of physical science. Three main themes were identified during the research: 1. Grade 10 learners’ experience of physical science is related to the psychosocial characteristics of the learner and his/her interaction with the environment. 2. Grade 10 learners’ experience of physical science is related to the method of instruction or the teaching method thereof in the classroom. 3. Grade 10 learners’ experience of physical science is related to the educators’ attitude, words and actions towards learners during the teaching of physical science.These three themes can be further substantiated by the following categories: • The feedback loop between the learners’ ability to understand physical science and their self-image in the presence of other learners. • Learners experience a love-hate relationship with physical science influenced by their ability to understand the subject. • Implementing practical activities such as experiments, practical assignments and attending science outings makes the subject more interesting, fun and able to understand. • Group activities in learning about physical science adds to the experience of it being fun and enable learners to learn more about others. • Physical science taught by relating its meaning in the learners "real life" is more interesting and easier to understand. • A context created where learners feel "comfortable with the teacher" promotes the approachability of the educator. • Disrespectful practices demonstrated by educators, lead to a negative experience of physical science. • Educators verbalising work pressure and showing stress related to the teaching of physical science increase the pressure and stress learners experience about the subject. Recommendations that could assist learners’ achievement in physical science should focus on facilitating a positive experience of the subject. It should takethe themes and categories of this study into consideration. Some important recommendations are: • Further research is required to find appropriate ways to enable educators and curriculum designers to successfully build systematic understanding of science through everyday knowledge and interests of learners. • The current physical science curriculum is national or universal but it should be locally defined. The curriculum should respond to local interests and needs. Science education will then be of immediate use to the learners and promote concept development that is more effective. It will also result in greater achievement of “critical outcomes” like problem solving, critical thinking, application of knowledge and teamwork. • Further research is needed to explain the negative correlation between learners’ attitude and perceptions towards physical science and their achievement in the subject. • The context of the physical science classroom has to be investigated to identify what the nature and style of teaching and activities are that engage learners in physical science. • More research is needed to examine instructional strategies in the classroom for improving all learners’ experience of physical science and achievement in science. The researcher experienced the research as very fulfilling and challenging. She realised that there are numerous possibilities within the physical science classroom where educators can influence their learners’ achievement
A psycho-educational programme for educators for the management of aggression in a secondary ESBD (emotional, social and behaviour disorders) school in the United Kingdom
Get PDFPh.D. (Education)Education in the United Kingdom is divided into three stages which are: primary, secondary, further and higher education. Learners’ compulsory education lasts for 11 years. Legal schooling ages are starting from five years to 16 years. Within that period learners must obtain full-time education that is suitable to their age, ability, capacity and their special educational needs (SEN). If a learner does not attend a school, the local education authority (LEA) must be satisfied that other appropriate provision is available for them. Transferring age from primary to secondary school is at the age of 11 years. Most secondary schools in the United Kingdom are comprehensive; which means that they do not operate a selective entrance system. However, in some parts of the United Kingdom, grammar school systems operates which usually requires learners to pass an entrance examination based on their ability
The statistical theory underlying human genetic linkage analysis based on quantitative data from extended families
No full textMagister Scientiae - MScTraditionally in human genetic linkage analysis, extended families were only used in the analysis of dichotomous traits, such as Disease/No Disease. For quantitative traits, analyses initially focused on data from family trios (for example, mother, father, and child) or sib-pairs. Recently however, there have been two very important developments in genetics: It became clear that if the disease status of several generations of a family is known and their genetic information is obtained, researchers can pinpoint which pieces of genetic material are linked to the disease or trait. It also became evident that if a trait is quantitative (numerical), as blood pressure or viral loads are, rather than dichotomous, one has much more power for the same sample size. This led to the development of statistical mixed models which could incorporate all the features of the data, including the degree of relationship between each pair of family members. This is necessary because a parent-child pair definitely shares half their genetic material, whereas a pair of cousins share, on average, only an eighth. The statistical methods involved here have however been developed by geneticists, for their specific studies, so there does not seem to be a unified and general description of the theory underlying the methods. The aim of this dissertation is to explain in a unified and statistically comprehensive manner, the theory involved in the analysis of quantitative trait genetic data from extended families. The focus is on linkage analysis: what it is and what it aims to do. There is a step-by-step build up to it, starting with an introduction to genetic epidemiology. This includes an explanation of the relevant genetic terminology. There is also an application section where an appropriate human genetic family dataset is analysed, illustrating the methods explained in the theory sections.South Afric
The statistical theory underlying human genetic linkage analysis based on quantitative data from extended families
Get PDFMagister Scientiae - MScTraditionally in human genetic linkage analysis, extended families were only used in the analysis of dichotomous traits, such as Disease/No Disease. For quantitative traits, analyses initially focused on data from family trios (for example, mother, father, and child) or sib-pairs. Recently however, there have been two very important developments in genetics: It became clear that if the disease status of several generations of a family is known and their genetic information is obtained, researchers can pinpoint which pieces of genetic material are linked to the disease or trait. It also became evident that if a trait is quantitative (numerical), as blood pressure or viral loads are, rather than dichotomous, one has much more power for the same sample size. This led to the development of statistical mixed models which could incorporate all the features of the data, including the degree of relationship between each pair of family members. This is necessary because a parent-child pair definitely shares half their genetic material, whereas a pair of cousins share, on average, only an eighth. The statistical methods involved here have however been developed by geneticists, for their specific studies, so there does not seem to be a unified and general description of the theory underlying the methods. The aim of this dissertation is to explain in a unified and statistically comprehensive manner, the theory involved in the analysis of quantitative trait genetic data from extended families. The focus is on linkage analysis: what it is and what it aims to do. There is a step-by-step build up to it, starting with an introduction to genetic epidemiology. This includes an explanation of the relevant genetic terminology. There is also an application section where an appropriate human genetic family dataset is analysed, illustrating the methods explained in the theory sections.South Afric
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Estimating the burden of disease attributable to lead exposure in South Africa in 2000
No full textObjectives\ud
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To estimate the burden of disease attributable to lead exposure in South Africa in 2000. \ud
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Design\ud
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World Health Organization comparative risk assessment (CRA) methodology was followed. Recent community studies were used to derive mean blood lead concentrations in adults and children in urban and rural areas. Population-attributable fractions were calculated and applied to revised burden of disease estimates for the relevant disease categories for South Africa in the year 2000. Monte Carlo simulation-modelling techniques were used for the uncertainty analysis. \ud
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Setting\ud
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South Africa. \ud
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Subjects\ud
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Children under 5 and adults 30 years and older. \ud
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Outcome measures\ud
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Cardiovascular mortality and disability-adjusted life years (DALYs) in adults 30 years and older and mild mental disability DALYs in children under 5 years. \ud
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Results\ud
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Lead exposure was estimated to cause 1 428 deaths (95% uncertainty interval 1 086-1 772) or 0.27% (95% uncertainty interval: 0.21 - 0.34%) of all deaths in South Africa in 2000. Burden of disease attributed to lead exposure was dominated by mild mental disability in young children, accounting for 75% of the total 58 939 (95% uncertainty interval 55 413 - 62 500) attributable DALYs. Cardiovascular disease in adults accounted for the remainder of the burden. \ud
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Conclusions\ud
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Even with the phasing out of leaded petrol, exposure to lead from its ongoing addition to paint, paraoccupational exposure and its use in backyard 'cottage industries' will continue to be an important public health hazard in South Africa for decades. Young children, especially those from disadvantaged communities, remain particularly vulnerable to lead exposure and poisoning
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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