Bibliography: pages 353-378. / Defying widespread predictions, the tricameral Parliament not only continues to function but, after five years, has become an integral part of the political realities in South Africa. This thesis is concerned with an assessment of the dynamics of the new dispensation in general and the role played by the Houses of Representatives and Delegates in particular. It evaluates the implications of the new dispensation for the government, participants in government created, racially segregated bodies and the extra-Parliamentary opposition. In addition, it synthesizes empirical data and theory by applying concepts of ethnicity and by reviewing the tricameral system in the light of the theoretical discussions on consociation and "control". The general elections of September 1989 have been used as a cut-off point for this study because the poll amongst Coloureds and Indians provides an opportunity to observe the effects of the performance of the "other" two Houses. Although it is too early for an exhaustive evaluation of the tricameral system, three preliminary conclusions can be drawn. Firstly, despite its failure to gain legitimacy in wider circles, the new dispensation proved to be a qualified success for the government, particularly in so far as it has managed to involve Coloured and Indian participants in the administration of their "own" affairs. Secondly, after an acquiescent start the two new chambers began to utilize the not inconsiderable potential innate to the Constitution of 1983 but failed to bridge the gulf separating them from the mainstream of black opposition. Thirdly, events in and more significantly outside Parliament, seriously undermined the success of the boycott strategy employed by the extra-Parliamentary opposition. While conducting research into apartheid institutions it has become necessary to use official terminology, for example, whites, Coloureds, Indians, Africans. It goes without saying that this does not imply any measure of acceptance of government policy. The methodology of the study is outlined in a brief appendix.

Magister Educationis - MEd / Onderwyseropleiding, 'n integrende deel van die onderwysstelsel in die Republiek van Suid-Afrika, soos dit ook die geval in ander lande is, is die spil waarom die opheffing van en kulturoordrag van 'n nasie in die algemeen en die van 'n ontwikkelde gameenskap in die besonder draai. Sonder 'n onderwysstelsel, en meer belangrik, sonder 'n onderwyserskorps kan geen gemeenskap ver op die beskawingspad vorder nie.

Student Number : 0416521T - MSc(Med) dissertation - School of Pathology - Faculty of Health Sciences / Fetal alcohol spectrum disorder (FASD) encompasses a range of conditions induced by prenatal alcohol exposure. Fetal alcohol syndrome (FAS) is the most severe of these conditions. FAS is characterised by discriminating facial features along with growth deficiencies and central nervous system abnormalities. FASD is a growing concern in South Africa, particularly in the Northern and Western Cape Provinces. In the Northern Cape, astounding prevalence rates of 122 and 73.8 per 1000 school entry children have been established for the towns of De Aar and Upington respectively. Studies involving twin concordance research and animal models have indicated that there is a genetic influence contributing towards FAS susceptibility in individuals. FAS is considered a complex disease whereby both genetic and environmental factors interact in disease pathogenesis. For this reason a case-control study involving the investigation of appropriate candidate genes was conducted. The neuronal migration pathway in the developing brain is targeted by prenatal alcohol exposure. The astrotactin (ASTN) and reelin (RELN) genes were selected for investigation based on their fundamental role in neuronal migration. A FAS case-control study involving 45 cases and 112 controls was conducted on the Northern Cape Coloured population. Four single nucleotide polymorphisms (SNPs) including missense and non-coding variants were selected within ASTN and four missense SNPs were selected within RELN. The study aimed to determine the genotype and allele frequencies of the variants within the case and control groups and to assess whether any association between the gene variants and the predisposition to FAS existed. Statistical analyses indicated a significant genotypic association (P= 0.049) between RELN’s rs607755 marker; the C/T genotype was more likely to be found amongst controls thus inferring a possible protective effect against FAS. A logistic regression model supported the above association by indicating the C/T genotype as being independently significant (P= 0.026). The most limiting factor of this study was the small sample size and consequent lack of power to detect genes with minor effects. It would therefore be suggested that the study be repeated once a larger sample size has been established. A larger sample size would increase the chances of detecting true associations between genes of minor effect and FAS, thus minimising false-positive associations from arising.

<p> This thesis presents a new modelling technique for the complex current system. It integrates object-oriented methodology into Petri Nets formalism.</p> <p> Petri Nets are used for modelling concurrent systems. They have natural graphical representation as well as formal specifications. They have been successfully used in various industrial applications. But with the development of distributed and network systems, their traditional weakness, namely their inadequate support for compositionality, is a big obstacle to their practical use for large, complex systems. To address this problem, we introduce the Object-Oriented Coloured Petri Nets (OO-CPN), which integrates the powerful modularity of an object-oriented paradigm into Petri Nets formalism. OO-CPN is based on Coloured Petri Nets and supports the concepts of object, class, inheritance and polymorphism.</p> / Thesis / Master of Science (MSc)

No description available.

The thesis starts by providing a brief overview of South African ''Coloured" politics from the passing of Ordinance 50 in 1828 to the removal of the Cape Coloured people from the common voter's roll in 1956. It then goes on to discuss in detail the structures instituted by successive Nationalist Governments to serve as an alternative to parliamentary representation for the coloured people, the role of the various coloured political parties within such structures and the latter's gradual adaptation and development, culminating in the inauguration of the Tricameral Parliament in early 1985. The thesis is, on the one hand, a detailed record of coloured political activity following the loss of common roll voting rights in the Cape, focusing on specifically coloured political parties rather than on broader, non-ethnic resistance movements in which many coloured people took part during the same period. This covers the rise and rapid decline of a conservative grouping within the coloured community which sought to foster an exclusively coloured nationalism operating within the Government's policy of parallel development, and attempted to use the Coloured Persons' Representative Council as a means towards achieving the economic, social and political upliftment of the coloured people. It also deals with the important role of the Labour Party after 1966, showing how a moderate resistance movement carne to use the Council as a platform from which to confront the Government's apartheid policies and to render the institutions of parallel development unworkable through noncooperation and boycotting. The second important preoccupation of the thesis concerns the ambiguous and often contradictory attitudes towards the "coloured question" within the National Party itself. This ambivalence, it is argued, not only had much to do with the eventual failure of the Coloured Persons' Representative Council to become a viable substitute for Parliamentary representation acceptable to the majority of coloured people, but was also a primary cause of the National Party split in 1982. It shows too how the collapse of Grand Apartheid had its origins in the failure to incorporate the coloured population within its framework. The thesis is concerned primarily with coloured political developments. When relevant, however, the establishment and development of representative institutions for the Indian people is also dealt with, in so far as this overlaps with issues and events concerning the coloured Council. Finally, the five year period following the dissolution of the Coloured Persons' Representative Council in 1980 and the inauguration of the Tricameral Parliament in 1985 is briefly dealt with in a concluding chapter. This mainly concerns the gradual accommodation reached between the Government and the Labour Party when the latter eventually agreed, conditionally, to take part in the new constitution.

We study stochastic heat equations of the forms $[\partial_t u-\sL u]\d t\d x=\lambda\int_\R\sigma(u,h)\tilde{N}(\d t,\d x,\d h),$ and $[\partial_t u-\sL u]\d t\d x=\lambda\int_{\R^d}\sigma(u,h)N(\d t,\d x,\d h)$. Here, $u(0,x)=u_0(x)$ is a non-random initial function, $N$ a Poisson random measure with its intensity $\d t\d x\nu(\d h)$ and $\nu(\d h)$ a L\'vy measure; $\tilde$ is the compensated Poisson random measure and $\sL$ a generator of a L\'{e}vy process. The function $\sigma:\R\rightarrow\R$ is Lipschitz continuous and $\lambda>0$ the noise level. The above discontinuous noise driven equations are not always easy to handle. They are discontinuous analogues of the equation introduced in \cite{Foondun} and also more general than those considered in \cite{Saint}. We do not only compare the growth moments of the two equations with each other but also compare them with growth moments of the class of equations studied in \cite{Foondun}. Some of our results are significant generalisations of those given in \cite{Saint} while the rest are completely new. Second and first growth moments properties and estimates were obtained under some linear growth conditions on $\sigma$. We also consider $\sL:=-(-\Delta)^{\alpha/2}$, the generator of $\alpha$-stable processes and use some explicit bounds on its corresponding fractional heat kernel to obtain more precise results. We also show that when the solutions satisfy some non-linear growth conditions on $\sigma$, the solutions cease to exist for both compensated and non-compensated noise terms for different conditions on the initial function $u_0(x)$. We consider also fractional heat equations of the form $ \partial_t u(t,x)=-(-\Delta)^{\alpha/2}u(t,x)+\lambda\sigma(u(t,x)\dot{F}(t,x),\,\, \text{for}\,\, x\in\R^d,\,t>0,\,\alpha\in(1,2),$ where $\dot{F}$ denotes the Gaussian coloured noise. Under suitable assumptions, we show that the second moment $\E|u(t,x)|^2$ of the solution grows exponentially with time. In particular we give an affirmative answer to the open problem posed in \cite{Conus3}: given $u_0$ a positive function on a set of positive measure, does $\sup_{x\in\R^d}\E|u(t,x)|^2$ grow exponentially with time? Consequently we give the precise growth rate with respect to the parameter $\lambda$.

Thesis (PhD (Biomedical Sciences. Molecular Biology and Human Genetics))--University of Stellenbosch, 2009. / Dissertation presented for the degree of Doctor of Philosophy in Medical Biochemistry at Stellenbosch University. / ENGLISH ABSTRACT: The infectious disease tuberculosis (TB) still represents a global threat due to its devastating effect on health and the subsequent high mortality rate. Previous studies have indicated that host genetic factors are implicated in host susceptibility to TB. Since TB is a complex disease, it can be assumed that susceptibility to M. tuberculosis has multiple genetic causative factors (as well as environmental causes). The current study focussed on a number of South African Coloured (SAC) individuals, some of whom were TB cases and others controls. Population substructure was tested in the admixed SAC population as it can be a strong confounding factor for association studies. Our results using the programme STRUCTURE indicated no population substructure in the SAC population. We further investigated the population structure of the SAC group using Affymetrix 500k SNP chip data which showed that the SAC population group has 4 major ancestral components: the Khoesan, European, African and Asian (Indian). A number of candidate polymorphisms in eight genes, previously indicated to play an important role in TB susceptibility, were tested in case-control associations studies. We found statistically significant associations between IFNGR1, IL-8, IL-1Ra and NRAMP1 polymorphisms and TB susceptibility in the SAC population. It has become increasingly evident that gene-gene interactions play a far more important part in an individual’s susceptibility to a complex disease than single polymorphisms would on their own. The importance of epistasis was clearly identifiable in this study with only four associations found between the individual variants and TB susceptibility, but eight instances of statistically significant gene-gene interactions. A combined data set consisting of 106 variants constructed from our database and also used for gene-gene interaction analysis yielded numerous statistically significant interactions. The interaction between the genotype of the human host and the bacterial strain genotype was also investigated and yielded interesting results. Owing to various polymorphisms in several cytokine genes, the protein levels of the main modulators of the immune system, cytokines and chemokines, are changed in several diseases such as infectious diseases and may affect susceptibility or resistance to TB. The functional polymorphisms or haplotype patterns in some of these cytokine genes might be vital for protective immune responses and may serve as biomarkers of protection or susceptibility to TB. The present study investigated 18 cytokines including pro-inflammatory, anti-inflammatory and chemokine factors in healthy (mantoux positive or negative) children using the Linco-plex immunoassay, and investigated potential interactions. The basic research will one day contribute to personalised genetics which may benefit infectious diseases such as TB. If individuals can be identified as potentially more vulnerable, they may require different vaccination strategies, a higher index of suspicion if exposed to TB, and prophylactic treatment. / AFRIKAANSE OPSOMMING: Die infektiewe siekte tuberkulose (TB) is steeds ‘n gevaar wat die hele wêreld bedreig weens die groot impak op gesondheid en die gevolglike hoë mortaliteit. Vorige studies het bevind dat die gasheer se genetiese faktore wel betrokke mag wees by die gasheer se vatbaarheid vir TB. Aangesien TB ‘n komplekse siekte is, kan dit aanvaar word dat vatbaarheid tot M. tuberculosis veelvuldige genetiese oorsaaklike faktore (sowel as omgewingsoorsake) het. Hierdie studie het gefokus op ‘n aantal Suid-Afrikaanse Kleurling (SAC) individue, waarvan sommige TB pasiënte en ander kontroles was. Die gemengde SAC populasie is getoets vir populasie-stratifikasie, aangesien stratifikasie ‘n sterk verwarrende invloed op pasiënt-kontrole studies kan hê. Ons resultate is verkry met behulp van die program STRUCTURE en het aangedui dat daar geen populasie sub-struktuur tussen die pasiënte en kontroles was nie. Ons het ook die populasiesamestelling van die SAC groep ondersoek met data verkrygbaar van die Affymetrix 500k enkel nukleotied polimorfisme mikroskyfie. Hierdie data het getoon dat die SAC populasie uit 4 hoof voorouerlike komponente bestaan naamlik die Khoesan, Europeërs, Afrikane en Asiate (Indiërs). ‘n Aantal kandidaat polimorfismes in agt gene, wat volgens vorige studies ‘n belangrike rol in TB vatbaarheid te speel, was in hierdie pasiënt-kontrole assosiasie studie bestudeer. Ons het statistiese beduidende verwantskappe tussen IFNGR1, IL-8, IL-1Ra en NRAMP1 polimorfismes en TB vatbaarheid in die SAC populasie gevind. Dit het al hoe meer duidelik geword dat geen-geen interaksies ‘n baie belangriker rol in ‘n individu se vatbaarheid vir ‘n komplekse siekte speel as enkel polimorfismes op hul eie. Die belang van epistase kon duidelik in hierdie studie geïdentifiseer word met slegs vier assosiasies wat tussen die individuele variante en TB vatbaarheid gevind is, in vergelyking met agt statisties beduidende geen-geen interaksies. ‘n Gekombineerde datastel wat uit ons databasis saamgestel is en wat 106 variante bevat is ook in ‘n aparte geen-geen interaksie analise gebruik, wat verskeie statisties beduidende interaksies getoon het. Die interaksie tussen die menslike gasheer genotipe en die bakteriese stam genotipe is ook in hierdie studie ondersoek en het interessante resultate opgelewer. Veranderde proteïen uitdrukking van die hoofmoduleerders van die immuunsisteem, sitokine en chemokine, kom voor in verskeie siektes soos infektiewe siektes weens verskillende polimorfismes in verskeie sitokien-gene. Sulke polimorfismes kan ook vatbaarheid vir of weerstandigheid teen TB beïnvloed. Die funksionele polimorfismes of haplotipe patrone in sommige van hierdie sitokien-gene mag noodsaaklik wees vir beskermende immuunresponse en mag ook as biomerkers vir beskerming teen of vatbaarheid vir TB dien. Hierdie studie het 18 sitokiene (insluitend pro-inflammatoriese-, anti-inflammatoriese- en chemokiene faktore), sowel as potensiële interaksies in gesonde (mantoux positiewe of negatiewe) kinders, ondersoek met behulp van die Linco-plex immuno-analise. Hierdie basiese navorsing sal eendag in die toekoms bydrae tot persoonlike genetiese analises wat tot voordeel kan wees vir infektiewe siektes soos TB. Indien individue as potensieël meer vatbaar vir TB geïdentifiseer kan word, kan sulke persone ander vaksineringstrategieë sowel as voorkomende behandeling vereis.

The Belgian Coastal Zone (BCZ) in the Southern Bight of the North Sea is a highly dynamic and optically complex area. This is due to high non-algal particles (NAP) and coloured dissolved organic matter (CDOM) content which in spring adds together with undesirable blooms of the haptophyte Phaeocystis globosa. There is a need for improving the algorithms for chlorophyll a (chl a) retrieval in these highly turbid waters and for developing algorithms for species detection in order to attempt to create an early warning bloom system. This information will contribute to the knowledge of the extent and magnitude of the P. globosa bloom in Belgian waters. In this study, pure cultures of the main taxa present in the BCZ, diatoms and P. globosa, were combined with field measurements of light absorption of total particles, phytoplankton and dissolved material, pigment determination and phytoplankton counts to address the main objectives. Sampling was performed during 8 cruises covering winter, spring, summer and late summer, and along nearshore-offshore gradients from 2003 to 2006. The area is characterised by a high spatio-temporal variability of IOPs due to the high dynamics of the area in terms of currents, salinity gradients and biological production. During spring the presence of P. globosa modulates the IOPs across all the area, the particle absorption is significantly higher than summer and there is no significant coast-offshore variability for phytoplankton and CDOM. The design of chl a retrieval algorithms assumes negligible absorption of NAP and CDOM in the near infrared (NIR) and the use of a fixed value of specific phytoplankton absorption. It is shown that neglecting the NAP and CDOM absorption in the NIR will have a significant overestimation impact in retrieval of chl a. On the other hand, the specific phytoplankton absorption was found to be highly variable (0.015 „b 0.011 m2 mg chl a-1). Both results will affect directly the retrieved chl a. The spatial variability of CDOM was significant varying between 0.20-1.31 m-1 in the marine area and between 1.81-4.29 m-1 in the Scheldt estuary. CDOM was found to be related to salinity with conservative mixing within the Scheldt estuary and during some seasons in the BCZ, however deviations from conservative mixing suggest other inputs to the CDOM pool. Analyses of the spectral slope of the CDOM absorption curve revealed two main CDOM pools in the area, an allochthonous one delivered by the Scheldt estuary and an autochthonous one associated with the phytoplankton spring bloom decomposition. Algorithms for CDOM retrieval will be affected if the variability in the relation between CDOM and salinity is not taken into account. The optical characterisation of diatoms and P. globosa from the BCZ in pure cultures revealed that the main differences in the phytoplankton absorption spectra were found at 467 and 500 nm corresponding to the absorption of the pigments chlorophyll c3 (chl c3) characteristic of P. globosa and fucoxanthin, respectively. Accordingly, both the absorption at 467 nm and the ratio 500/467 nm were successfully used to discriminate the two taxa in cultures and field samples. This latter indicator was not preserved in the reflectance signal due to degradation of the signal when passing from absorption to reflectance, and thus could not be used for algorithm development. The spectral feature at 467 nm was later used as the basis for the development of a flag-type algorithm to detect chl c3 using either absorption or water-leaving reflectance data. Also, the correlation between the algorithm¡¦s retrieved chl c3 and P. globosa cell number allowed the quantification of the bloom. The main findings of this thesis highlight the importance of the IOPs characterisation for the improvement and development of ocean colour retrieval algorithms in these highly complex waters.

Bei der postmortalen Befunderhebung an Zähnen im Rahmen der Identifikation unbekannter Leichen besteht die Möglichkeit, dass zahnfarbene Füllungen übersehen oder fehlgedeutet werden. Daraus entstehende Diskrepanzen zu den antemortalen Daten können zu Problemen bei der Identifikation führen. Ziel der Ar-beit war daher die Ermittlung einer zuverlässigen und praxistauglichen Methode zum sicheren Erkennen von zahnfarbenen Zahnfüllungen bei der postmortalen Befunderhebung. Dazu wurden 50 menschliche Zähne mit zahnfarbenen Füllungen versorgt und mittels UV-Licht, digitaler IR-Fotografie, digitalem Röntgen, CT und einer Schmelzfärbemethode bezüglich der Erkennbarkeit der Füllungen untersucht. Die geeignetsten Methoden wurden zusätzlich anhand von Farbfotografien in Fragebögen beurteilt. Die Schmelzfärbemethode erwies sich als die genauste Methode, aber auch mit Hilfe der UV-Fluoreszenz konnten mit 97% nahezu alle Füllungen erkannt werden. Die Röntgendiagnostik ermöglichte das Erkennen von 80% der vorhandenen zahnfarbenen Füllungen. Das CT ist unzuverlässig und die Infrarot-Fotografie ist ungeeignet für diese Fragestellung. Im Ergebnis dieser Studie kann die verbesserte Schmelzfärbung als sicherste Me-thode zur postmortalen Identifikation von zahnfarbenen Füllungen empfohlen wer-den. Als zuverlässige und schnelle „Screening Methode“ ist die Untersuchung mittels UV-Fluoreszenz geeignet. Für den sicheren Einsatz der UV-Fluoreszenz in der Rechtsmedizin sollten die Fähigkeiten der Rechtsmediziner im Umgang mit dieser Methode anhand praktischer Übungen geschult werden.