Volatility is a fascinating and important topic for financial markets in general, and probably the single most important issue in financial risk management. Although volatility itself is not synonymous with risk, it is closely associated with it in the realm of risk management. In this study, I focus on the volatility in the foreign exchange markets and investigate the spillover of volatility from this market to equity correlations and its impact on global equity markets’ bid-ask spreads as a proxy for market quality. I also explore the role that accounting earnings quality play in subsequent volatility in U.S. equity markets. I provide a theoretical base and its associated empirics for the link between exchange rate volatilities and global equity correlations. I test this theory using multiple techniques that ends with the application of autoregressive error correction analysis, wherein, I demonstrate the predictive power of options implied exchange rate volatilities against ex-ante global equity correlations. My findings indicate that exchange rate implied volatilities, coupled with one-period ex-post correlations, are more predictive of subsequent equity market correlations than other models. I then examine the impact of currency volatilities on the average monthly spreads in ADRs and their underlying local shares. I employ dynamic panel data estimation and principal component analysis to show that currency volatility explains a significant portion (16.6%) of the variation in spreads across markets, heretofore largely unexplored by extant finance literature. Finally, I employ well established accrual measures to calculate aggregate accruals for the S&P 500 on a quarterly basis and examine the ability of this aggregate measure to forecast future trends in the volatility of the index. I find a statistically significant relation between subsequent twelve-month volatility in the S&P 500 index and aggregate accruals. This relation holds whether total or abnormal accruals measures are employed. My findings document a rare long-term indicator of volatility in the widely followed index. I also show that my aggregate accrual measure yields additional information about S&P 500 volatility when compared with simple historical volatility measures or option implied volatility.

Content and Language Integrated Learning (CLIL) is an innovative educational approach in which an additional language is used for the learning and teaching of both language and subject content. Content and Language Integrated Learning is not commonly used in South African classrooms, but its application internationally has been shown by empirical research to significantly improve overall language competence in the target language. Reports indicate increased learner motivation and support for the learning of the content subject. This study sought to consider whether CLIL intervention would improve both language and science skills amongst Grade 8 learners in a Natural Sciences classroom. The researcher used a concurrent embedded mixed method design, including both quantitative and qualitative methodologies to gather data. An experimental test design with English Home Language classes and Afrikaans Home Language classes was employed. Hypothesis Testing was used as a statistical analysis to compare the pre-test and post-test results in order to ascertain the impact of CLIL intervention. In addition, the poster-activity and an open-ended questionnaire was used to qualitatively ascertain the impact of CLIL on learner literacy skills. The results showed that CLIL intervention improved learner performance significantly when compared to learners who were not exposed to CLIL. In addition, CLIL lessons were perceived as effective and learners verified that the approach was beneficial to their learning process.

The research reported in this thesis is concerned with the flow of granular systems in response to penetration and compaction. The technique of Digital Speckle Radiography (DSR), which involves analysis of flash X-ray images, has been applied to measure the internal displacement fields within large opaque granular samples. Large samples are desirable as the measured displacements are more representative of the bulk. Current DICC algorithms were found to be unsuitable for analysis of X-ray images of large samples. The large contrast variations present in such X-ray images, due to the X-ray beam profile, sample geometry and the high X-ray absorbance of metal penetrators, are shown to cause significant errors in the calculated displacement fields. A study of image normalisation techniques was carried out, and the effect of each technique on the accuracy of the measured displacements was investigated. A new DICC algorithm for use in DSR was produced which includes image normalisation techniques to correct for uneven contrast in the images. This new DICC algorithm was shown to be far more effective at analysing X-ray images of large samples. This improved DSR technique was applied to measure the internal displacements within a large sample of sand during penetration by projectiles with different nose-shapes (flat, ogive-2 and hemispherical) and at different rates (1.5 mm/min to 200 m/s). The improved technique was found to provide high-resolution displacement data illustrating the response of the material. The dominant material response at low rates (1.5 mm/min) was found to be splitting of the material ahead of the projectile tip, followed by bulk reverse-flow of material towards the penetration face. At the higher rates (200 m/s), the dominant response was compaction of the material ahead of the projectile tip. The transition between the two regimes was found to occur between velocities of 5 and 19 m/s. The streamlined ogive-2 projectile nose-shape was shown to be the most effective for penetration, in that it caused less disruption of the material ahead of the projectile, lost less energy during the early stages of penetration in the dynamic experiments and more effectively split the material ahead of the projectile tip, a process which was shown to be important at all rates of penetration. The compaction properties of a particulate mixture and a granular material, including the effect of factors such as porosity, initial particle arrangement and force chain formation, were investigated. Samples which were conducive to the formation of force chains spanning the whole sample were discovered to have anomalously high strengths. Small amounts of added water were shown to increase the compactability, by lubricating the grain contact points, but larger amounts of water decreased the compactability.

This thesis presents measurements of the the spin correlation strength in top anti-top quark pair production at the LHC using the ATLAS detector. The data used corresponds to 4.6 fb−1 of integrated luminosity taken during 2011 at the LHC at a center of mass energy of 7 TeV. The spin correlation is studied utilising different observables with different sensitivities to the production mechanism, in particular to gluon-gluon fusion in the like or unlike helicity state, quark anti- quark annihilation in the unlike helicity state, or a combination of the three. In addition cuts are made on the invariant mass of the ttbar system to enhance or suppress contributions from different initial state production mechanisms. The analysis presented is a precision test of both ttbar production and decay in the SM. These measurements are compared to the most current theoretical predictions. No deviation from the SM expectation was observed. In a subset of the data, corresponding to an integrated luminosity of 2.1 fb−1, the hypothesis of zero spin correlation is excluded at 5.1 standard deviations.

In current mammography practice, radiologists typically view mammograms in a symmetric, side-by-side, configuration in the belief that abnormalities will be made salient because they break the perceived symmetry. The literature on the use of symmetry as an aid to signal detection is limited and this thesis has taken a psychophysical approach to investigate the radiologist’s task of detecting a small mass (a blob) in paired mammogram backgrounds. Initial experiments used Gaussian white noise and synthetic mammogram backgrounds to test observer performance for the radiologist’s task using symmetric (side-by-side) displays and animated (the two images of a pair alternated sequentially in the same location) displays. The use of animated displays was then tested using real mammogram backgrounds in the subsequent experiments. The results showed that side-by-side presentation of paired images does not provide any benefit for the detection of a blob, whereas, alternated presentation enabled the observer to use the correlation present between the paired images to improve detection performance. The effect of alternation was not evident when applied to the task of detecting a small mass in real mammogram pairs and subsequent investigation suggested that the loss of effect resulted from the lack of scale invariance of real images. This meant that, regardless of the level of global correlation between two images, the localised correlation, at a region size reflecting the visual angle subtended by the fovea, was much lower. Thus, decorrelation by the visual system was ineffective and performance for the detection of a blob in the paired images was also ineffective. This thesis suggests that, whilst animated displays can be a powerful tool for the identification of differences between paired images, the underpinning mechanism of decorrelation makes them unsuited for mammograms where scale invariance means that correlation at local levels is a fraction of the global correlation level.

Microhemodynamics is the study of blood flow in small vessels, usually on the order of 50 to 100 µm. The in vitro study of blood flow in small channels is analogous to the in vivo study of the microcirculation. At this scale the Reynolds and Womersly numbers are significantly less than 1 and the viscous stress and pressure gradient are the main determinant of flow. Blood is a non-homogeneous, non-Newtonian fluid and this complex composition and behavior has a greater impact at the microscale. A key parameter is the shear stress at the wall, which is involved in many processes such as platelet activation, gas exchange, embryogenesis and angiogenesis. In order to measure the shear rate in these blood flows the velocity profile must be measured. The measured profile can be characterized by the maximum velocity, the flow rate, the shear rate at the wall, or a shape parameter reflecting the bluntness of the velocity profile. The technique of micro-particle image velocimetry (µPIV) was investigated to measure the velocity profiles of blood microflows. The material of the channel, the type of tracer particles, the camera used, and the choice in data processing were all validated to improve the overall accuracy of µPIV as a blood microflow measurement method. The knowledge gained through these experiments is of immediate interest to applications such as the design of lab-on-a-chip components for blood analysis, analysis of blood flow behavior, understanding the shear stress on blood in the microcirculation and blood substitute analysis. Polymer channels were fabricated from polydimethylsiloxane (PDMS) by soft lithography in a clean room. PDMS was chosen for ease of fabrication and biocompatibility. The contacting properties of saline, water, and blood with various polymer channel materials was measured. As PDMS is naturally hydrophilic, surface treatment options were explored. Oxygenated plasma treatment was found to be less beneficial for blood than for water. The choice of camera and tracer particles were validated. Generally, for in vivo studies, red blood cells (RBCs) are used as tracer particles for the µPIV method, while for in vitro studies, artificial fluorescent micro particles are added to the blood. It is demonstrated here that the use of RBCs as tracer particles creates a large depth of correlation (DOC), which can approach the size of vessel itself and decreases the accuracy of the method. Next, the accuracy of each method is compared directly. Pulsed images used in conjunction with fluorescing tracer particles are shown to give results closest to theoretical approximations. The effect of the various post-processing methods currently available were compared for accuracy and computation time. It was shown that changing the amount of overlap in the post-processing parameters affects the results by nearly 10%. Using the greatest amount of correlation window overlap with elongated windows aligned with the flow was shown to give the best results when coupled with a image pre-processing method previously published for microflows of water. Finally the developed method was applied to a relevant biomedical engineering problem: the evaluation of blood substitutes and blood viscosity modifiers. Alginate is a frequently used viscosity modifier which has many uses in industry, including biomedical applications. Here the effect of alginate on the blood rheology, i.e., the shape of the velocity profile and the maximum velocity of blood flow in microchannels, was investigated. Alginate was found to blunt the shape of the velocity profile while also decreasing the shear rate at the wall. Overall, the accuracy of µPIV measurements of blood flows has been improved by this thesis. The work presented here has extended the known methods and accuracy issues of blood flow measurements in µPIV, improved the understanding of the blood velocity profile behavior, and applied that knowledge and methods to interesting, relevant problems in biomedical and biofluids engineering.

Cold rolled aluminum is a widely used metal in industry. The forming limit diagram (FLD) which is commonly used to predict safe deformation parameters currently fails to predict the uniform elongation after non-proportional strain path often found in industrial operations. In this work, a non-proportional strain path change in aluminum alloy 3104 going from plane strain tension to uniaxial tension was investigated. Plane strain tensile tests have been carried out to various pre-strains (3%, 6% and 9%), followed by uniaxial tensile tests at various orientation with respect to the tensile direction (0°, 45° and 90°). Digital image correlation (DIC) was employed to analyze the strain distribution in the sample during deformation. The mechanical response was studied as a function of pre-strain and reloading angle to quantify the effect of strain path change on AA3104.

The process of in vitro-in vivo extrapolation (IVIVE) can be used to predict pharmacokinetics of drugs in patients using data from in vitro systems. This process relies on the use of experimentally obtained scaling factors, such as abundances of different drug-metabolising enzymes and microsomal protein content (MPPGL). The use of simulators is dependent on abundances and activities of pharmacokinetically relevant enzymes. The incorporation of inter-individual variability in abundances of enzymes, correlations between enzyme expression patterns, and relationships between genetic, physiological, and environmental factors and enzyme expression and activity can make predictions using IVIVE and simulations of pharmacokinetic experiments in virtual populations more accurate and realistic. Incorporation of variability and correlations can also assist in predicting extreme cases where drug therapy may be ineffective or may cause adverse effects. A meta-analysis of 52 studies was carried out to assess the reported abundances of cytochrome P450 and uridine glucuronosyltransferase (UGT) enzymes in adult Caucasian subjects. Some heterogeneity was found between studies and the weighted means and overall coefficients of variation were calculated. Some strong enzyme expression correlations were identified; CYP3A4/CYP3A5*1/*3 (rs = 0.66, p < 0.0001, n = 37), CYP3A4/CYP2C8 (rs = 0.79, p < 0.0001, n = 107), and CYP2C8/CYP2C9 (rs = 0.71, p < 0.0001, n = 72). A quantitative protocol based on targeted proteomics was used to quantify cytochrome P450 and UGT enzymes in adult liver samples (n = 24). The QconCAT standard used for quantification was successfully expressed in-house after optimisation of the expression protocol, and the utility of two strategies in expressing recalcitrant QconCAT proteins was highlighted; the use of a fusion partner and reshuffling the order of peptides in the sequence. The enzymes quantified in this study were CYP1A2, 2A6, 2B6, 2C8, 2C9, 2C18, 2D6, 2J2, 3A4, 3A5, 3A7, 3A43, and 4F2, and UGT1A1, 1A3, 1A4, 1A6, 1A9, 2B4, 2B7, and 2B15. Correlations of expression identified in the meta-analysis were confirmed and new correlations were demonstrated between UGT enzymes and between enzymes from the two families. Correlations between UGT enzymes were particularly strong and statistically significant. Relationships between enzyme expression levels and genotype, age, sex, smoking, and alcohol consumption were investigated. A significant effect of genotype on expression was seen for CYP3A5 (p < 0.0001). An overall moderate decline of expression with age was observed for all the enzymes under study; however, this relationship was not statistically significant in most cases. Gender did not have a considerable effect on expression, although some differences in expression were observed between male and female donors. Smoking seemed to induce the expression of all enzymes; however, statistically significant induction was demonstrated only in the cases of CYP2A6, CYP3A4, CYP3A7, and UGT1A1 (p < 0.05). Alcohol consumption was not shown to have a considerable effect on enzyme expression. Two pig livers were used to optimise some aspects of the experimental protocol including solubilisation and digestion of proteins. Pig MPPGL was measured and relative hepatic contents of drug-metabolising cytochrome P450 enzymes in pig liver were established using label-free quantification.

Ti-6Al-4V is the most widely used titanium alloy and is typically used in stages of gas turbine engines, due to its high strength-to-weight ratio, corrosion resistance and high strength at moderate temperatures. However, the alloy is susceptible to the development of strong textures during thermomechanical processing that leads to a preferred crystallographic orientation. These are referred to as macrozones and are thought to develop during the β to α phase transformation, as a result of the retention of large prior β grains during processing and variant selection. Macrozones are clusters of neighbouring grains with a common crystallographic orientation that may act as one single grain during loading and have been shown to cause scatter in the fatigue life. The focus of the current work was based on the analysing the strain behaviour of soft, hard and no macrozones within the microstructure, during various loading conditions. The local strain behaviour was studied at a micro and nanoscale, using the digital image correlation (DIC) technique, which utilises microstructural images recorded during mechanical loading. On a microscale, the no-macrozone and strong-macrozone condition loaded at 0% exhibited homogeneous strain behaviour. The strong-macrozone condition loaded at 45% and 90% to the extrusion direction, respectively, developed pronounced high strain bands correlating to regions that were favourably oriented for prismatic and basal slip, respectively. Characterisation of the slip bands provided a detailed understanding of the deformation behaviour at the nanoscale and the slip system was subsequently determined for each grain using slip trace analysis. Prismatic slip was the dominant slip system in all conditions, particularly in the soft-oriented macrozone regions of the strong-macrozone condition loaded at 45 degrees. Shear strains of 10 times the appliedstrain were observed. Further investigations on the strong-macrozone condition loaded at 45 degrees to ED during standard and dwell fatigue demonstrated early failure in the dwell sample, with higher strain accumulation for dwell.

Although language is a medium of learning, most educational institutions typically teach and therefore evaluate language separately from content. In second language contexts, recent attention has been given to language/content integration through content-based language instruction. Yet, questions of integrative evaluation (evaluating language and content as one) remain uncertain and difficult. This inquiry explores difficulties invoked when teachers engage in practices of integrative evaluation of English language learners' writing at an international college for Japanese nationals in Canada. Are these difficulties technical problems? Technical rationality has been critiqued by a number of thinkers. Those interested in action research practices, contrast technical rationality with what they call reflective rationality and argue for contextualizing, rather than simplifying, difficult situations. Some with hermeneutic interests argue for an attunement to, rather than concealment of, difficulties of life in the classroom. Others interested in writing instruction, are critical of conventional approaches to writing pedagogy as reductionistic and deterministic. There are a number of instances of difficulty in teachers' integrative evaluation practices. Prior to agreeing on a prompt, many teachers explore texts as interpretive, social literacy but, in their uncertainty of how to mark such a text, they return to a question for which there is a 'correct' and 'controlled' response. Once the prompt and evaluative criteria are established, discordant orientations to evaluation, literacy, and language/content integration complicate teachers' uncertainty. For example, teachers sometimes acknowledge functional views of language/content integration, yet they are vague and uncertain about how to mark in an integrated way. When teachers read texts prior to judgment, they comment that the texts are difficult to interpret and then impose their own 'straightforward' readings on the texts to reduce and simplify the difficulties. These instances raise serious concerns in practices of evaluation, literacy and language/content integration, especially when technical forms of evaluation are paradoxically aligned with social and integrated texts. A turn to hermeneutics troubles a technical hold and invites further inquiry into tensioned moments of integrative evaluation as difficult, living practices. / Education, Faculty of / Language and Literacy Education (LLED), Department of / Graduate