Magister Commercii - MCom / As a result of high economic inequality, widespread discontent with excessive chief executive officer (CEO) compensation levels is acute in South Africa (SA). Some commentators argue that instead of high levels of CEO pay causing inequality, it may be part of the solution if higher levels of CEO compensation translate into better company performance, so reducing unemployment. International studies investigating the relationship between CEO short-term cash compensation and current company performance generally report a weak or no relationship where accounting based measures of performance are used. Developments in the international literature reflect a stronger relationship when long-term incentive compensation (LIC) is included and total shareholder return (TSR) used to measure company performance. However, a concerning negative association between the highest paid CEOs in terms of excess LIC and future abnormal TSR is reported. In contrast, SA pay-performance research is largely not reflective of the developments in the international literature, with local studies mostly finding no pay-performance relationship, except where size-related accounting measures are used. As a result of the strong correlation between CEO pay and company size reported in the international literature, and local studies not adequately controlling for company size, the accuracy of the conclusions drawn in prior studies on the pay-performance sensitivity relationship in SA are brought into question. This study addresses the gaps in the SA literature by investigating the relationship between the size-adjusted excess CEO compensation and future abnormal TSR for the top 100 SA companies listed on the Johannesburg Stock Exchange for the period 2011 to 2013. A positive relationship is found between future abnormal TSR and short-term cash compensation, but not LIC. The levels and structure of CEO compensation in SA is also described.

The Public Hurricane Model developed at FIU by a team of scientists has to be certified by the Florida Commission on Hurricane Loss Projection Methodology. The commission ensures that all hurricane loss models meet certain standards, as models are used extensively by regulators and insurance firms to produce inputs used in the homeowner insurance rate making process. The focus of this thesis is to conduct sensitivity and uncertainty analysis through the calculation of standardized regression coefficients and expected percentage reductions in expected loss costs in order to meet the commission standards. The commission approved the model after very extensive and rigorous review by a panel of experts. The results generated for sensitivity and uncertainty, form S-6, showed the importance of the Holland B parameter regardless of hurricane category, with the radius of maximum winds increasing in importance for stronger hurricanes.

A follow-up of traditional medicinal plants uses is an important tool in highlighting their therapeutic potentials, as they have been found to be a source of a wide range of bioactive compounds that can be used as base compounds for new pharmaceutical drugs. This study therefore focuses on assessing the anti-Listerial properties of the seeds of Garcinia kola (Heckel) plant, which is a traditional medicinal plant of west and central African origin, and was and is still used to traditionally treat several ailments. Four different solvents crude extracts of the seeds were assessed for their anti-Listerial activities in-vitro, against a panel of 42 Listeria bacteria, which included Listeria monocytogenes, Listeria ivanovii and Listeria grayi species. At 10 mg/ml concentration the aqueous extract had activity against 29% of the test isolates while the other three crude extracts namely dichloromethane, n-hexane and the methanol extracts had activity against 45% of the test bacteria. The minimum inhibitory concentration (MIC) ranges of the extracts were 0.079-0.313 mg/ml for the dichloromethane extract; 0.079-0.625 mg/ml for the n-hexane extract; 0.157-0.625 mg/ml for the methanol extract; and 10->10 mg/ml for the aqueous extract. The minimum bactericidal concentration (MBC) ranges of the extracts were 0.625–10 mg/ml for both the n-hexane and the dichloromethane extract; 5-10 mg/ml for the methanol extract; and those for the aqueous extract were above 10 mg/ml against all the susceptible Listeria isolates. The rate of kill analysis was then determined for the three most active crude extracts that is excluding the aqueous extract and it was assessed against four representative Listeria species namely L. monocytogenes (LAL 8), L. grayi (LAL 15), L. ivanovii (LEL 30) and L. ivanovii (LEL 18). All the three extracts showed a general trend of being concentration and time dependent in their rate of kill profiles such that most bacteria cells were killed at the highest test concentration of 4× MIC value after the maximum exposure time of 2 h. The n-hexane, dichloromethane and methanol extracts were bactericidal against 4, 3 and 1 isolates out of the four test Listeria isolates respectively.

The n-Hexane, dichloromethane, methanol and aqueous crude extracts of Garcinia kola (Heckel) seeds were screened for their anti-Vibrio activities against 50 Vibrio bacteria isolated from wastewater final effluents. The 50 isolates consisted of different Vibrio species namely V. fluvialis (14), V. vulnificus (12), V. parahaemolyticus (12), V. metschnikovii (3) and 9 others unidentified to the specie level. The n-Hexane, dichloromethane and methanol extracts had activities against 16 (32 percent) of the Vibrio isolates, while the aqueous extracts had activities against 12 (24 percent) all at a screening concentration of 10 mg/ml. The minimum inhibitory concentrations (MICs) were 0.313-0.625 mg/ml, 0.313-0.625 mg/ml, 0.313-2.5 mg/ml and 10 mg/ml for n-Hexane, dichloromethane, methanol and aqueous extracts respectively. Rate of kill studies were carried out against three different Vibrio species namely V. vulnificus (AL042), V. parahaemolyticus (AL049) and V. fluvialis ( AL040) using the n-Hexane, dichloromethane and methanol extracts at 1× to 4 × MICs and 2 hour exposure. About 96.3 percent, 82.2 percent, and 78.1 percent (V. fluvialis AL040); 92.6 percent, 87.8 percent and 68.9 percent (V. parahaemolyticus AL049); and 91.6 percent, 64.4 percent, 60 percent (V. vulnificus AL042) of the bacteria were killed by the crude n-Hexane, dichloromethane and methanol extracts respectively after 2 hour exposure time at 4× MIC. The patterns of activity were bacteriostatic, with the n-Hexane extracts being most effective in activity. We conclude that the Garcinia kola seeds have promise in the treatment and management of infections caused by Vibrio species.

To calculate the sensitivity and specificity of multifocal electroretinography (mfERG) in detection of chloroquine and hydroxychloroquine retinal toxicity, 120 eyes of 63 patients were evaluated using the currently recommended diagnostic tests. The results were compared to those of 54 eyes of 28 control subjects. The sensitivity and specificity of mfERG relative to the combination of automated visual fields and optical coherence tomography (the reference test) were calculated to be 87% and 86.5% respectively. However, analysis of the “false positive” cases proved that mfERG was more sensitive than the reference test and the actual sensitivity and specificity values were higher than the results of this study. Reduction of mfERG amplitude was a strong and reliable sign of early retinal toxicity and was correlated with the cumulative dose of hydroxychloroquine. This correlation was not observed with the reference test quantitative values.

Type 2 diabetes mellitus (T2DM) continues to be a national challenge for Canadians. African and Caribbean Immigrants are among the most affected groups and those at risk of developing comorbidities and related complications. It continues to prove challenging to treat T2DM for the affected individuals. Effectively treating the disease can help mitigate risk factors for related comorbidities and complications while improving the quality of life for those affected. There is increasing research, outside of Canada, showing the evidence for the effectiveness of culturally sensitive and adapted interventions to immigrant patients affected with T2DM. In light of the effectiveness of such interventions in many industrialized nations, a systematic review (SR) can offer the best evidence for the scope and consideration of such treatment approaches in Canada. This SR aimed to determine whether community-based diabetic interventions in Canada, are culturally sensitive to African and Caribbean minorities living with type II diabetes. A narrative synthesis was employed to report the effect of interventions seeking to affect outcomes of T2DM patients in Canada. Of the 63 articles included for full review, 60 were excluded for not meeting the criteria of having the target population explicitly identified and also not having any mention of cultural sensitivity. Three articles were included for the final review because the target population was explicitly identified. The final results showed that all interventions were found not to be culturally sensitive to African and Caribbean T2DM patients in Canada. Our results suggest a lack in Canadian literature. To the best of our knowledge, this is the very first systematic review on this subject matter in Canada. This review provides dependable information and recommendations to researchers, educators, clinicians, and policy makers for future research with T2DM African and Caribbean patients in Canada. RÉSUMÉ Le diabète de type 2 demeure un défi national pour les Canadiens. Les immigrants d’origine d’Afrique et des Caraïbes sont parmi les groupes les plus frappés et l'un des plus à risque de développer des troubles comorbides et de complications liées au diabète. Traiter le diabète continue à poser un défi chez les personnes affectées. Traiter efficacement cette maladie peut contribuer à réduire des principaux facteurs de risque quant aux troubles comorbides et complications, tout en améliorant la qualité de vie chez les personnes affectées. Un nombre grandissant de recherche, hors du Canada, démontrent avec des preuves concluantes que les interventions sensibles et culturellement adaptées aux immigrants affectés par le diabète sont efficaces. Étant donné l'efficacité de ces interventions dans nombreux pays industrialisés, une revue systématique peut nous offrir la meilleure preuve pour l'envergure relative à ce genre de traitement au Canada. La présente étude méthodique vise à déterminer si les interventions contre le diabète, en milieu communautaires au Canada, sont culturellement adaptées aux minorités ethniques d’origines d’Afrique et des Caraïbes souffrant de diabète de type II. Une synthèse narrative a été utilisée afin de signaler les effets des interventions par rapport aux résultats des patients souffrant du diabète de type 2. Parmi les 63 articles considérés pour une évaluation complète, 60 ont été exclus car ni la population cible ou la mention de la sensibilité culturelle n’a été explicitement identifiée. Trois articles ont été inclus pour l’évaluation finale car la population cible fut explicitement identifiée. Aucune des interventions n’est culturellement sensible aux patients Africains et Caribéen affecté par le diabète de type 2. Nos résultats démontrent un écart dans la littérature Canadienne. A ce que nous sachons, cette revue systématique est la première qui touche à cette question au Canada. Cette revue fournie des données fiables et recommandations qui permettront aux chercheurs, enseignants, cliniciens, et aux décideurs en matière de politiques de santé pour des recherches futures auprès des patients Africains et Caribéen souffrants du diabète de type 2 au Canada.

The following thesis is focused on the use of Monte Carlo simulation in business valuation. It examines the theoretical context of the valuation process and simulation techniques and subsequently applies these to the valuation of Plzeňský Prazdroj, a. s. as of 31.3.2008. The aim was to explore the potential of application of Monte Carlo simulation and to interpret obtained information. There was created the valuation model and performed sensitivity analysis based on which there were identified factors which have significant impact on the value. These were further investigated and characterized in terms of probability. Following the extension of the model to include uncertainty factors there was simulated business value in relation to the variability of uncertainty factors and the result was subsequently interpreted. It was concluded that Monte Carlo simulation may be useful predominantly in search for subjective value for investor due to additional information obtained.

The altitude at which oxygen supplementation should commence to be administered to aircrew in South Africa, flying in unpressurised aircraft is 12,000 feet. Above that altitude effects of reduced tissue oxygen content (hypoxia) become significant. Vision is particularly sensitive to hypoxia, and it was decided to test visual parameters at 12,000 feet to see if there were any subtle changes which might impair flight safety. It this were so, the level at which oxygen supplementation should commence would have to be lowered. The visual parameters to be assessed, all important in aviation, were colour vision, contrast sensitivity, and the presence of phorias (potential squints). 37 Healthy volunteers had these parameters assessed in an altitude chamber at ground level, 8,000 feet and 12,000 feet. Analysis of the results revealed no clinically significant degradation of vision at 12,000 feet, and it was concluded that the present altitude at which oxygen supplementation should begin (12,000 feet) is appropriate. It was advised that further testing should take place in subjects based at sea level. / Dissertation (MSc)--University of Pretoria, 2006. / School of Health Systems and Public Health (SHSPH) / Unrestricted

Current irrigation scheduling technologies are limited to refilling the root zone based on measured or predicted amount of water stored within the root zone. This needs measurement of soil-water status and specifying soil field capacity that make this approach expensive and challenging. The FullStopTM wetting front detector (FS) was specifically developed to be a simple and affordable technology to help farmers manage water, nutrients and salts in the root zone. This device responds to a strong wetting front, but research has shown it is less sensitive to weak redistributing wetting fronts, and this may compromise its efficacy in certain situations. The objectives of this study were to recommend a modified version of the FS that responds to weak redistributing wetting fronts and to develop guidelines for the deployment of these detectors to schedule irrigation. The research described herein comprises of two phases: the first phase focused on literature review, field evaluation of wetting front detector of varying sensitivities (WFD) and laboratory measurements of hydraulic properties of soil and wick materials. The second phase validates the HYDRUS-2D/3D for the development of guidelines on how to use WFD to schedule irrigation. The first phase includes: i) a literature review on passive lysimetry that relates design features to the sensitivity of WFD and how prototypes of WFD operate; ii) hydraulic characterization of soil and wick materials to describe the functioning of the different WFD designs; iii) an empirical investigation to determine whether the wick characteristics limits the attainment of equilibrium between the opening of the outer tube and the water table in the inner tube; iv) field evaluations of five types of WFD under sprinkler and natural rainfall to examine the accuracy and sensitivity of the different WFD designs; and v) analysis of the equilibrium between the WFD and the surrounding soil, and recommendations for the best design options based on the sensitivity requirement for different situations. The second phase of the study used observed data sets to validate the Hydrus-2D/3D model. After validation, the model was used to simulate different irrigation scenarios to develop guidelines for the deployment of WFD to schedule irrigation. Field evaluations of various WFD designs showed that length has significant effect on the sensitivity of WFD (P ≤ 0.05). The 90-cm-long Tube wetting front detector (90TD) was significantly more sensitive than the original FS design. The hydraulic conductivity function of two wick materials (Diatomaceous Earth and Fine sand) were not limiting for the attainment of the equilibrium between the Tube Detector and the surrounding soil, and the opening of the Tube Detector and the water level in the inner tube. The Hydrus-2D/3D model performed well in simulating the measured responses of FS or 90TD and the experimental sensitivity thresholds of these detectors. This model was deployed to link WFD responses to different simulated irrigation scenarios to generate monitoring protocol such as detector placement depth, irrigation amount or interval. The model simulations showed that FS can be used to schedule irrigation objectively for sprinkler or drip irrigations, i.e. adjusting irrigation amount or interval based on the response of a detector. Though further study is warranted, model simulation has indicated that 90TD can be used to improving furrow irrigation management. It is envisaged that WFD technology can guide farmers to make informed irrigation decisions and alerting farmers to percolation losses below the root zone. / Thesis (PhD)--University of Pretoria, 2014 / gm2015 / Plant Production and Soil Science / PhD / Unrestricted

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-04-19T13:52:47Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação Wemerson Finalizada.pdf: 9160369 bytes, checksum: b31280e4154dafd68b3a566de187171f (MD5) / Made available in DSpace on 2016-04-19T13:52:47Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação Wemerson Finalizada.pdf: 9160369 bytes, checksum: b31280e4154dafd68b3a566de187171f (MD5) Previous issue date: 2015-03-16 / CNPq / A presente pesquisa teve como objetivo entender o comportamento do canal fluvial em área urbana denominado de riacho Umas localizado na cidade de Camaragibe, município que pertence a Região Metropolitana do Recife. O intuito foi observar a dinâmica de processo-resposta entre regime pluviométrico de 2014 e as perturbações ocorridas sobre o canal fluvial, e, todavia, a sensitividade do respectivo canal. Além dos transtornos e riscos trazidos a população ribeirinha residente próxima ao canal, portanto configurando-se como trabalho em escala de detalhe. As dinâmicas atmosféricas foram verificadas a partir da análise rítmica observadas pelos gráficos de pluviosidade diária e imagens de satélite. As respostas sobre o canal fluvial (riacho Umas) foram analisadas em três cenários que correspondem a um período seco (menor pluviosidade) e dois úmidos (casos significativos de maior pluviosidade). Contudo os períodos úmidos divididos em cenário pós-evento de perturbação e cenário durante o evento de perturbação, ou seja, ao longo do processo de precipitação significativa. Para as análises espaciais confeccionaram-se mapas de detalhe de direção de fluxo, curvatura das encostas, declividade, que, todavia, estes foram correlacionados com o mapa de uso e ocupação do solo do município de Camaragibe. Mesmo sendo uma escala espacial de detalhe verificaram-se respostas variáveis (dinâmica não linear) sobre o canal com base em suas características naturais e formas de ocupação e uso do solo, fazendo com que a vulnerabilidade da população que ocupa a área também ocorra modo diferente diante ocorrência de inundações. Também foi realizada a análise das assembleias de relevo fluvial e interfluvial com intuito de compreender a relação de conectividade, principalmente em relação aos fluxos hídricos, entre vertentes e canal fluvial. / This paper has the objective to comprehend the behavior of the fluvial pass named Umas stream, located in the urban area of Camaragibe city, municipality in the Metropolitan Area of Recife. The intention was to observe the process-response dynamics between the pluviometric rate of 2014 and the disturbances occurred at the fluvial pass, and, yet, the sensitivity of the same stream. Considering the disturbance and risks brought to the riverside population, so constituting it as a detail scale paper. The atmospheric dynamics was verified from a rhythmic analysis, observing the daily pluviometric graphs and satellite images. The answers concerning the fluvial pass (Umas stream) were analyzed in three scenarios corresponding to one dry stage and two humid stages. Considering the humid stages divided in: post-disturbance-event scenario and during-disturbance-event scenario, that is, along the significant precipitation process. Even though being a spacial detail scale, variable answers (non-linear dynamics) were found about the stream based on its natural characteristics and soil’s occupation/using methods, making the vulnerability of the occupier population also occur in a different manner due to the occurrence of floods. Also was made an analysis of fluvial and interfluvial relief assembly, pointing to understand the connectivity relation, mainly, to the hydric flow between watersheds and streams. Therefore, flow direction detail, hillside curvature and declination maps were made, and, still, were correlated to the soil’s using and occupation map of Camaragibe’s municipality.