This dissertation is devoted to the study of self-similar groups and related topics. It consists of three parts. The first part is devoted to the study of examples of finitely generated amenable groups for which every finitely presented cover contains non-abelian free subgroups. The study of these examples was motivated by natural questions about finiteness properties of finitely generated groups. We show that many examples of amenable self-similar groups studied in the literature cannot be covered by finitely presented amenable groups. We investigate the class of contracting self-similar groups from this perspective and formulate a general result which is used to detect this property. As an application we show that almost all known examples of groups of intermediate growth cannot be covered by finitely presented amenable groups. The latter is related to the problem of the existence of finitely presented groups of intermediate growth. The second part focuses on the study of one important example of a self-similar group called the first Grigorchuk group G, from the viewpoint of pro finite groups. We investigate finite quotients of this group related to presentations and group (co)homology. As an outcome of this investigation we prove that the pro finite completion G_hat of this group is not finitely presented as a pro finite group. The last part focuses on a class of recursive group presentations known as L-presentations, which appear in the study of self-similar groups. We investigate the relation of such presentations with the normal subgroup structure of finitely presented groups and show that normal subgroups with finite cyclic quotient of finitely presented groups have such presentations. We apply this result to finitely presented indicable groups without free sub-semigroups.

The purpose of the study was to investigate the implementation of learning support strategies by Intermediate Phase teachers. The study also determined the factors (enhancing or limiting) that impact upon the successful implementation of learning support strategies specifically in a rural school. The study was conducted at one primary school in the Western Cape. The research participants were ten teachers involved in offering learner support at this school. Focus group discussions as well as in-depth interviews were used to explore the teachers’ views of their support strategies. The data was analysed using a thematic approach. The main finding of this study is that a huge gap exists between inclusive education policy expectations and the actual manifestation of teachers’ support to learners with learning difficulties. The findings of the study reveal a combination of external as well as internal and systemic factors working in conjunction and culminating in a lack of capacity amongst teachers. This study recommends a review of policies with the aim of providing opportunities for a thorough understanding of new concepts and practices, focussed and professional development of teachers in the area of learner support and more monetary and infrastructural resources.

The embryonic mouse inner ear was used as a model with which to study ototoxicity and tissue interactions. The inner ear anlage can be explanted and cultured in vitro from about the 12th gestational day (gd), and will differentiate parallel with the inner ear developing in vivo until a time corresponding to birth (21st gd). During this period the ovoid sac develops into the labyrinth. In the present thesis work, otic anlagen from gd 12, 13, 13.5, 15 and 16 were used. As a rule the explants were kept in culture until a time point equivalent to the 21st gd. Analyses using freeze-fracture technique and transmission electron microscopy showed that in cultured 13th gd otocysts the development of junctional complexes followed the same principal pattern as in vivo. Tight junctions develop into many strands lying parallel to the apical surface of all epithelial cells. Uncoupling of the hair cells occurs with loss of gap junctions. Some tight junctions had an aberrant appearence, with in part very thick strands and strands running at right angles to the apical surface. All aminoglycosides are potentially ototoxic. In the inner ear, outer hair cells of the organ of Corti and vestibular type I hair cells are affected by these antibiotics. The access route to the hair cells and the sites and mechanisms of action of aminoglycosides are not precisely defined. The uptake of tritiated tobramycin in 16th gd inner ears was studied. An initial rapid uptake of the drug, within 10 min, was followed by a slower accumulation, reaching a steady state after 60 min. Most of the tobramycin was bound reversibly, at least after a short period of incubation (2 h). The irreversibly bound fraction was of the same magnitude as the uptake within 10 min. Uptake took place against a concentration gradient. The otocyst can differentiate even without the statoacoustic ganglion. The interaction of the sensory epithelium with the ganglion was investigated by explanting the statoacoustic ganglion without target tissue. Twenty-five percent of the ganglions survived and had outgrowth of neurites but there was no differentiation into either the cochlear or vestibular type of neuron cells. Exposure of cultured otocysts (13 or 13.5 gd) to l-azetidine-2-carboxylic acid, a 1-proline analog that disrupts formation of collagen, resulted in retarded morphogenesis of the labyrinth and a dose- dependent derangement of the basal lamina. The expression of intermediate filaments (IFs) was analysed using monoclonal antibodies. The same IF pattem was found in cultured inner ears as in vivo. Explants were taken on 13th, 15th or 16th gd. Exposure to gentamicin, ethacrynic acid or cisplatin did not alter the IF composition. Cytokeratins (CKs) 8 and 18 were identified in all inner ear epithelia. In addition CKs 7 and 19 were visualized in the epithelia involved in maintaining endolymph homeostasis. The ganglion cells showed coexpression of CK, vimentin and neurofilaments. The elemental composition of the endolymph compartment of 16th gd inner ears cultured for 5 days was studied using energy-dispersive X-ray microanalysis. Na to K ratios characteristic of endolymph were found. / <p>S. 1-34: sammanfattning, s. 37-88: Härtill 6 uppsatser</p> / digitalisering@umu

As transistors size and power limitations stroke computer industry, hardware parallelism arose as the solution, bringing old forgotten problems back into equation to solve the existing limitations of current parallel technologies. Compilers regain focus by being the most relevant puzzle piece in the quest for the expected computer performance improvements predicted by Moores law no longer possible without parallelism. Parallel research is mainly focused in either the language or architectural aspects, not really giving the needed attention to compiler problems, being the reason for the weak compiler support by many parallel languages or architectures, not allowing to exploit performance to the best. This thesis addresses these problems by presenting: Erbium, a low level streaming data-flow language supporting multiple producer and consumer task communication; a very efficient runtime implementation for x86 architectures also addressing other types of architectures; a compiler integration of the language as an intermediate representation in GCC; a study of the language primitives dependencies, allowing compilers to further optimise the Erbium code not only through specific parallel optimisations but also through traditional compiler optimisations, such as partial redundancy elimination and dead code elimination.

No description available.

This study explores teachers' beliefs, views and experiences of the design principles of integration, progression and infusion in the Life Orientation (LO) curriculum at the Intermediate Phase level. Integration, progression and infusion are integral to the South Africa Curriculum Statement and the LO curriculum in particular, as they serve the connection, sequence and technique of linking different learning contents. The aims of the study were: (i) to determine to which extent if any can the principles of feminism be used to influence curriculum integration, progression and infusion in the LO curriculum; (ii) to use different theories of feminism to enhance our understanding of curriculum integration, progression and infusion in the LO curriculum; (iii) to determine teachers' beliefs and experiences of curriculum integration, progression and infusion in the LO curriculum. To achieve these aims, on a theoretical level, I synthesised and analysed different theories of feminist discourses into different themes such as location, caring relations, knowing and thinking. These themes were related to the principles of curriculum integration, progression and infusion and these were used as a frame of reference to make suggestions on the various ways to enhance LO teachers' classroom practice of integration, progression and infusion at the Intermediate Phase. Empirically, I explored the LO teachers' views, beliefs and experiences. Consequently, I situated the study in an interpretative paradigm. I used qualitative research design and methodology with a phenomenological approach, by means of unstructured interviews, classroom observations and focus-group interviews. Three primary schools were purposefully selected for the study. The three principals of the schools were interviewed for the unstructured interviews while nine teachers were interviewed in three focus groups. To strengthen the interviews, I observed nine LO classrooms. The data that I generated as a result of the study were analysed by means of content analyses. The themes that emerged were categorised into different classes, namely: lack of adequate consultation, learning content repetition, learning content outdatedness, learning content irrelevancy, among others. It was deduced that these themes which formed the participants' experiences of integration, progression and infusion in the LO curriculum were arrived at as a result of their inherent approach which was described as a one-dimensional approach. A one-dimensional approach is that which stipulates a step-by- step approach to the design of curriculum. The Multi-dimensional approach embedded in multiple realities underpinning feminist discourses was suggested as an alternative. A multi-dimensional approach to the design of the curriculum includes the active contribution of various individuals to curriculum design. / Thesis (MEd (Curriculum Development))--North-West University, Potchefstroom Campus, 2013

This study explores teachers' beliefs, views and experiences of the design principles of integration, progression and infusion in the Life Orientation (LO) curriculum at the Intermediate Phase level. Integration, progression and infusion are integral to the South Africa Curriculum Statement and the LO curriculum in particular, as they serve the connection, sequence and technique of linking different learning contents. The aims of the study were: (i) to determine to which extent if any can the principles of feminism be used to influence curriculum integration, progression and infusion in the LO curriculum; (ii) to use different theories of feminism to enhance our understanding of curriculum integration, progression and infusion in the LO curriculum; (iii) to determine teachers' beliefs and experiences of curriculum integration, progression and infusion in the LO curriculum. To achieve these aims, on a theoretical level, I synthesised and analysed different theories of feminist discourses into different themes such as location, caring relations, knowing and thinking. These themes were related to the principles of curriculum integration, progression and infusion and these were used as a frame of reference to make suggestions on the various ways to enhance LO teachers' classroom practice of integration, progression and infusion at the Intermediate Phase. Empirically, I explored the LO teachers' views, beliefs and experiences. Consequently, I situated the study in an interpretative paradigm. I used qualitative research design and methodology with a phenomenological approach, by means of unstructured interviews, classroom observations and focus-group interviews. Three primary schools were purposefully selected for the study. The three principals of the schools were interviewed for the unstructured interviews while nine teachers were interviewed in three focus groups. To strengthen the interviews, I observed nine LO classrooms. The data that I generated as a result of the study were analysed by means of content analyses. The themes that emerged were categorised into different classes, namely: lack of adequate consultation, learning content repetition, learning content outdatedness, learning content irrelevancy, among others. It was deduced that these themes which formed the participants' experiences of integration, progression and infusion in the LO curriculum were arrived at as a result of their inherent approach which was described as a one-dimensional approach. A one-dimensional approach is that which stipulates a step-by- step approach to the design of curriculum. The Multi-dimensional approach embedded in multiple realities underpinning feminist discourses was suggested as an alternative. A multi-dimensional approach to the design of the curriculum includes the active contribution of various individuals to curriculum design. / Thesis (MEd (Curriculum Development))--North-West University, Potchefstroom Campus, 2013

In the field of second language acquisition, there are few studies focusing on Chinese English-as-an-additional-language (EAL) graduate students’ communication strategy use, strategy use across different disciplines, and the relationships between communication strategy use and learners’ speaking performance. To fill the gap identified in the literature reviewed, this study examined the communication strategies used by 11 Chinese EAL graduate students from the Departments of Electrical Engineering and Education in the completion of two informal debate tasks with a questionnaire adapted from Nakatani’s (2006) Oral Communication Strategy Inventory and two post-task communication strategy recall questionnaires. Results from the study indicate that participants used eight categories of communication strategies, with fluency-oriented strategies the most frequently used strategy category and translation the least frequently used strategy category. Advanced English-language proficiency level learners used more social affective, message reduction and alteration, and negotiation of meaning strategies than learners at high-intermediate proficiency levels, to a degree that was statistically significant. No significant difference was identified in the overall communication strategy use but in one instance of individual strategy use (i.e., clarifying stance) across two disciplines. Significantly positive relationships were identified among certain categories of communication strategies (i.e., social affective, negotiation of meaning, accuracy-oriented strategies, and message reduction and alteration strategies), individual strategies (i.e., turn yielding, exemplifying, clarifying meaning, correcting others, referring to notes for accuracy/fluency, message reduction and alteration), and participants’ speaking performance. In addition, the retrospective results from the post-task strategy recall questionnaires suggest that participants in this study are not fully aware of their communication strategy use. The findings in this study can inform language practitioners’ of communication strategies used by Chinese graduate students majoring in Electrical Engineering and Education. Implications and future research directions are discussed in light of the findings derived from the present study that can further contribute to research about EAL learners’ communication strategies used at the graduate level. / Graduate / 0290 / cihangzh@uvic.ca

The problem statement for this study is, "an investigation towards the experience of intermediate phase educators in the George district of the implementation of inclusive education in their schools". Firstly a literature review was perfomed on the implementation of inclusive education in South Africa and overseas, which revealed a diversity of opinions about the implementation of inclusive education, and that the various countries experience varying demands and successes in the implementation thereof. The empirical research performed thereafter was qualitative in nature, to explore the experience of intermediate phase educators in the George district of the implementation of inclusive education in their schools. The results of the empirical research indicate that the educators experience various barriers themselves regarding the implementation of inclusive education in their schools, inter alia a great diversity of learners in their classes which puts demands on their time and attention to those learners, a number of factors that hamper the learning process, lack of parental involvement, insufficient learning support materials to fulfil the needs of learners, and most of all the experience of a lack knowledge and skills in themselves to identify and support barriers to learning in learners. The study concludes with a summary and recommendations. / Thesis (MEd (Learner Support))--North-West University, Potchefstroom Campus, 2012

A shool-based support programme for the intermedediate learner wuth depression This study is aimed at determining whether a school-based support programme can aid the intermediate learner with depression in decreasing his depression levels. It focuses on: the world of experience of the intermediate learner with depression; the role of the school as an overall health-promoting environment; and the creation of a school-based support programme for the intermediate learner with depression. The learner (the intermediate learner included) spends most of the day at school, so the educator can play an important role in identifying and following up problems and getting the school to function as a health-promoting environment. South African schools are focused mainly on primary and tertiary intervention, while secondary intervention reveals a serious deficiency. In the empirical investigation, 16 intermediate learners who were identified with depression were, involved in a purposeful convenience test sample by means of the CDI questionnaire. There was an experimental and a control group of eight members respectively. According to the results of the pretestposttest, the school-based support programme in which the experimental group participated caused their depression levels to decrease significantly. The need for a school support programme for the intermediate learner with depression was validated from this point of view. / Thesis (Ph.D. (Education))--North-West University, Vaal Triangle Campus, 2005.