O objetivo dessa tese foi avaliar alguns desses fatores, verificar a influência da ortodontia sobre alterações oclusais, limiares de dor à pressão da região orofacial, hábitos orais parafuncionais, e percepção de qualidade de vida. Foram selecionados 111 pacientes com idade entre 13 e 55 anos e ausência de sintomas de DTM que iniciaram terapia ortodôntica corretiva. O experimento foi dividido em três etapas: t1 (no momento da instalação do aparelho), t2 (2 meses após o início do tratamento), e t3 (6 meses após o início do tratamento). Em todas etapas os pacientes foram examinados clinicamente para avaliação oclusal e seus limiares de dor à pressão foram avaliados com um algômetro digital. Também foram aplicados questionários sobre hábitos orais parafuncionais (OBC) e percepção de saúde oral na qualidade de vida (OHIP-14br). Foram feitas comparações a respeito de cada variável quantitativa considerando os três tempos de avaliação por meio de Análise de variância (ANOVA) a um critério. O teste t foi utilizado para avaliar diferenças entre as médias das variáveis quantitativas no tempo inicial (t1) e tempo final (t3) de avaliação. Para avaliar o efeito da ortodontia sobre variáveis qualitativas oclusais foi utilizado o teste exato de Fisher. Foram considerados estatisticamente significantes aqueles resultados que apresentaram nível de significância igual ou menor que 0,05. Nenhum dos 111 pacientes desenvolveram sintomas de DTM até o momento final de avaliação. Não foram observadas mudanças oclusais quantitativas significativas (p>0,05) entre t1 e t3, no entanto os fatores qualitativos como mudanças nos padrões oclusais foram alterados significativamente (p<0,05). O tratamento ortodôntico não alterou os limiares de dor à pressão, mas foi observado um aumento significativo (p<0,05) nos escores de OHIP entre os períodos t1 e t3. O tratamento ortodôntico também não aumentou ou diminuiu a presença de hábitos orais parafuncionais, e não foram encontradas diferenças entre sexo e Limear de Dor a Pressão (LDP) nos indivíduos que possuíam mais ou menos hábitos. No entanto, pacientes mais velhos relataram maiores escores de OBC, e foi encontrada correlação entre pacientes com maiores escores de OBC e menores escores para o OHIP. O estudo concluiu que a movimentação ortodôntica não teve efeito sobre limiares de dor na região orofacial e não influencia na presença de hábitos orais parafuncionais. No entanto, o tratamento ortodôntico teve um efeito positivo sobre a percepção de saúde oral na qualidade de vida. / The aim of this thesis was to evaluate some of these factors, examining the influence of orthodontics on occlusal changes, pain pressure thresholds of the orofacial region, parafunctional oral habits, and the perception of quality of life. 111 patients aged 13 to 55 that showed no signs or symptoms of TMD and began orthodontic treatment were selected. The experiment was divided into three phases: t1 (when the orthodontic device was installed), t2 (two months after the installation), and t3 (six months after the start of the treatment). At all phases, the patients were examined clinically for occlusal evaluation and their pain pressure thresholds were assessed with an analog algometer. They were also applied questionnaires on parafunctional oral habits (OBC) and perception of oral health on the quality of life (OHIP-14br). Comparisons were made with respect to each quantitative variable considering the three phases of evaluation through a one-way analysis of variance (ANOVA) for each variable. The t test was used to assess differences between the means of quantitative variables at baseline (T1) and the final evaluation (t3). To evaluate the effect of orthodontics on occlusal qualitative variables Fisher\'s exact test was used. Statistical significance was considered for those results with a significance level equal to or less than 0.05. None of the 111 patients developed symptoms of TMD within the evaluation time. No significant occlusal quantitative changes were observed (p> 0.05) between t1 and t3, however the qualitative factors considered as occlusal patterns were significantly changed (p <0.05). Orthodontic treatment did not alter pain pressure thresholds but a significant increase (p <0.05) in scores of OHIP was observed between phases t1 and t3. Orthodontic treatment did not increase or decrease the pesence of parafunctional oral habits, and no differences were found between sex and LDP in individuals who possessed more/less parafunctional habits. However, older patients reported higher OBC scores, and correlation was found between patients with higher OBC scores and lower scores for OHIP. The study concluded that orthodontic treatment did not have an effect on orofacial pain hresholds, nor the presence of parafunctional oral habits. The perception of oral health on quality of life improved significantly with treatment and patients with lessparafunctional oral habits presented a better quality of life.

A Articulação Temporomandibular (ATM) pode ser acometida por inúmeros distúrbios articulares sendo os mais comuns os distúrbios de desarranjo do disco e os distúrbios inflamatórios. Um sinal clínico importante nesses casos é a sensibilidade dolorosa à palpação digital ou por mensuração do Limiar de Dor à Pressão (LDP), determinado com o uso de um instrumento denominado algômetro. O presente trabalho tem o objetivo de determinar qual o valor de LDP que melhor diferencie ATMs saudáveis daquelas acometidas por distúrbios inflamatórios e dolorosos. Ainda propõem-se a determinar se há diferenças entre o LDP de ATMs saudáveis e ATMs com deslocamento de disco com redução (DDCR) assintomáticos. Para isso, foi utilizada uma amostra de 60 indivíduos de ambos os gêneros com idade entre 18 e 50 anos, avaliados pelos critérios do Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) e divididos em três grupos: 20 indivíduos com diagnóstico clínico de artralgia da ATM (com ou sem deslocamento de disco para anterior, 20 indivíduos com diagnóstico clínico de DDCR (assintomáticos) e 20 indivíduos sem dores ou ruídos na ATM (grupo controle). Toda a amostra foi submetida a exame de ressonância magnética para análise da posição do disco para confirmar o exame físico e validar os critérios de inclusão (RDC/TMD) para formação dos grupos. Foram realizados exames de algometria sobre o pólo lateral das ATMs, e obtidas Escalas de Análise Visual (EAV) para o grupo de artralgia. Os dados foram analisados por teste de análise de variância (ANOVA a um critério) e por teste de correlação de Pearson com 5% de significância. Níveis de especificidade e sensibilidade, sendo gerada curva ROC foram também determinados. O valores de LDP foram significantemente menores para o grupo com artralgia (média de 1,07 kgf/cm2 ± 0,445), quando comparados aos outros grupos. Ainda, o grupo com DDCR (média de 1,90 kgf/cm2 ± 0,647) apresentou menores valores quando comparados ao controle (média de 2,46 kgf/cm2 ± 0,593). Não foi encontrada correlação entre o LDP obtido no grupo de artralgia com a EAV e com o tempo de experiência de dor. Quando excelentes valores de sensibilidade e especificidade foram contemplados, verificou-se que o valor de palpação de 1,56 kgf/cm2 é o mais adequado para o diagnóstico de DTM de origem articular. / Temporomandibular Joint (TMJ) internal derangements are characterized by anterior disk displacement (ADD) and/or as arthralgias. An important clinical presentation in these cases is the painful tenderness to manual palpation or decreased Pressure Pain Threshold (PPT), determined with an algometer. The present study aims to determine, based on high specificity levels, the more appropriate PPT value to discriminate healthy TMJs from those with painful inflammatory processes as well as to determine the influence of asymptomatic disk displacement with reduction (DDWR) in this scenario. A sample of 60 individuals from both genders with age between 18 and 50 years were evaluated by Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and divided into three groups: 20 patients with clinical diagnosis of TMJ arthralgia, 20 patients with clinical diagnosis of asymptomatic DDWR and 20 individuals with no TMJ pain or noise (control group). All individuals were submitted to an exam of magnetic resonance imaging for the analysis of disk position to confirm the physical exam (RDC/TMD) and to validate the group distribution. An algometry exam was performed on the TMJ lateral pole and the individuals of the arthralgia group also filled out a Visual Analogue Scale (VAS). The data were analyzed by variance test (ANOVA) and by Pearson correlation test with 5% of significance. Levels of specificity and sensibility, and ROC curves were also determined. The arthralgia group presented significant lower PPT (mean of 1.07 kgf/cm2 ± 0.445) values than the others. DDWR group (mean of 1.90 kgf/cm2 ± 0.647) has shown significant lower PPT values when compared to the control group (mean of 2.46 kgf/cm2 ± 0.593). A significant correlation between the PPT and the VAS and the time of pain experience was not found. 100% of specificity and 90% of sensitivity were obtained when 1.56 kgf/cm2 was applied to the TMJ (ROC=0.99). This value was considered to be the most appropriate to detected TMJ arthralgia.

Master of Science / Department of Computing and Information Sciences / William H. Hsu / The project explores the possibility of increasing efficiency in the clusters formed out of massive data sets which are formed using threshold blocking algorithm. Clusters thus formed are denser and qualitative. Clusters that are formed out of individual clustering algorithms alone, do not necessarily eliminate outliers and the clusters generated can be complex, or improperly distributed over the data set. The threshold blocking algorithm, a current research paper from Michael Higgins of Statistics Department on other hand, in comparison with existing algorithms performs better in forming the dense and distinctive units with predefined threshold. Developing a hybridized algorithm by implementing the existing clustering algorithms to re-cluster these units thus formed is part of this project. Clustering on the seeds thus formed from threshold blocking Algorithm, eases the task of clustering to the existing algorithm by eliminating the overhead of worrying about the outliers. Also, the clusters thus generated are more representative of the whole. Also, since the threshold blocking algorithm is proven to be fast and efficient, we now can predict a lot more decisions from large data sets in less time. Predicting the similar songs from Million Song Data Set using such a hybridized algorithm is considered as the data set for the evaluation of this goal.

Master of Science / Department of Computing and Information Sciences / William H. Hsu / (Higgins, Savje, & Sekhon, 2016) Provides us with a sampling blocking algorithm that enables large and complex experiments to run in polynomial time without sacrificing the precision of estimates on a covariate dataset. The goal of this project is to run the different clustering algorithms on top of clusters formed from above mentioned blocking algorithm and analyze the performance and compatibility of the clustering algorithms. We first start with applying the blocking algorithm on a covariate dataset and once the clusters are formed, we then apply our clustering algorithm HAC (Hierarchical Agglomerative Clustering) or PAM (Partitioning Around Medoids) on the seeds of the clusters. This will help us to generate more similar clusters. We compare our performance and precision of our hybridized clustering techniques with the pure clustering techniques to identify a suitable hybridized blocking model.

‘The non-dialectical mean between which extremes are suspended constitutes something like an interface, which is the condition of the possibility and impossibility of seemingly seamless systems and structures. When radically conceived, this interface extends beyond every margin of difference to ‘contaminate’ opposites that once seemed fixed.’ (Taylor 1997: 269) The site is positioned at the juxtaposition of: poor opposite rich, inviting opposite closed, dense urban fabric opposite sprawling suburban, exclusive opposite inclusive. Therefore the question arise: when dealing with an island placed amidst these contradictions, how do you include and acknowledge all? By providing for the one inevitably leads to the exclusion of the other, yet again reinforcing the legacy apartheid left South African urban environments. Therefore, the search for the INbetween informs the merging of these realms by means of a public park and recreational youth facility at the juxtaposition of these contrasting realms. The merge creates a dynamic tension between public / private, rich / poor, active / contemplative, movement / rest and inside / outside which informs the design philosophy. The architecture investigates the fading of boundaries. The design problem is a youth facility with recreational, educational and counselling functions, for youth living within the inner city area of Hillbrow, Houghton, Berea and Parktown. It is part of the City of Johannesburg’s Child Friendly City Initiative (CFCI) and will be managed by Non Governmental Organisations (NGO) operating in the area. Therefore, the centre will be a facility of which youth can take ownership of. A platform for ‘accidental’ interaction between the people from these different communities. The centre needs to provide opportunities and facilities that would entice, intrigue and motivate in order to resist the attraction of street life and drugs, through the provision of recreational activities, entertainment, educational facilities in the form of skills and entrepreneurial training, counseling and medical assistance. / Dissertation (MArch(Prof))--University of Pretoria, 2007. / Architecture / unrestricted

Doctor of Philosophy / Department of Economics / Steven P. Cassou / This essay empirically investigates the dynamics between government debt and budget deficits in the United States during a recession as opposed to an expansion. We use four different budget deficits definitions to develop a more comprehensive insight. We estimate a threshold VAR model on quarterly data from 1947: Q1 to 2016: Q3 on debt to GDP and budget deficits to GDP ratio for the United States. Specification test using LR test rejects the null for a linear VAR against nonlinear VAR. The nonlinear impulse responses indicate, with an increase to budget deficits to GDP ratio, government debt to GDP ratio rise faster during a recession as opposed to an expansion, and tend to move in a counter-cyclical manner with an increase in the output gap. We can thus infer that governments chose economic stability over fiscal balance during recessions. With an increase in government debt to GDP ratio, nonlinear impulse response show budget deficits to GDP ratio grow faster during an expansion as opposed to a recession and exhibit counter-cyclicality with an increase in the output gap. All four budget defi cits definitions depict similar pattern. Robustness check, using cyclically adjusted primary budget deficit published by the congressional Budget Office, also con rm the above findings. In this essay, we explore the presence of a long run relationship between the monetary base and the government debt using monthly data from 1942:1 to 2015:12. We apply formal statistical methods including cointegration and threshold cointegration tests to investigate the presence of a long-run relationship and estimate a threshold vector error-correction model (TVECM henceforth) to analyze the short-run dynamics. We find the presence of a threshold cointegration between the monetary base and government debt. As for the short-run dynamics, TVECM estimates show that the speed of adjustment is significant for the growth in debt equation in both regimes with the signs indicating government adjusting the debt in the short-run. But the U.S. Fed does not change the monetary base, hence we do not find any evidence of debt monetization in the U.S. We evaluate our findings over two sub-samples: 1946 to 2015 and 1946 to 2007 for robustness purposes. Findings from both sub-samples conform to our findings from the full sample. In this essay, we investigate the impacts of growth in the budget deficit and money supply on real interest rate are integral to contemporary macroeconomic policy. We employ threshold VAR and nonlinear impulse responses using quarterly data from 1959 to 2015. We find that growth in money supply and budget deficits have an asymmetric impact on inflation, short-term interest rate, and real interest rates. Growth in money supply and budget deficit tend to make the real interest rate negative in a bad state. In a good state, on the other hand, growth in money supply tend to increase the real interest rate but growth in budget deficits tend to decrease the real interest rate over the forecast horizon.

The trustworthiness of the blood pressure (BP) readings acquired by oscillometric home-based monitoring systems is a challenging issue that requires patients to see the doctor for trusted measurements, especially those who are obese or have cardiovascular diseases such as hypertension or atrial fibrillation. Even with the most accurate monitors one may get different readings if BP is repeatedly measured. Trusted BP readings are those measured with accurate devices at proper measurement conditions. The accurate monitors need an indicator to assure the trustworthiness of the measured BP. In this work, a novel algorithm called the Dynamic Threshold Algorithm (DTA) is proposed that calculates trusted boundaries of the measured systolic and diastolic pressures from the recorded oscillometric waveforms. The DTA determines a threshold from the heart rate of subjects to locate the oscillometric pulse at the mean arterial pressure (PULSEMAP) and uses the peak, trough, and pressure of the located pulse to calculate the trusted boundaries. In terms of accuracy, a modeling approach is employed to estimate BP from the arterial lumen area oscillations model in the diastolic region (ALA-based). The model requires compliance parameter ‘c’ to estimate BP. To this end, a pre-developed linear regression model between ‘c’ and the corresponding amplitude ratio of the PULSEMAP is employed to evaluate ‘c’. The proposed method uses ‘c’ and estimates BP by minimizing differences between peak and trough amplitudes of the actual and corresponding simulated waveforms. The proposed DTA and ALA-based methods were tested on two datasets of healthy subjects and one dataset of sick subjects with cardiovascular diseases, and results were validated against corresponding references and compared with two popular maximum amplitude and maximum/minimum slope algorithms. Mean absolute error (MAE) and standard deviation of errors (STDE) are used to evaluate and compare the results. For healthy subjects, the MAE of the estimated systolic (SBP) and diastolic (DBP) blood pressures was improved up to 57% and 57% with an STDE of 55% and 62%, respectively. For sick subjects, the MAE was improved up to 40% and 29% with an STDE of 36% and 20% for SBP and DBP, respectively.

This investigation was concerned with measurements of middle ear muscle activity. Specifically, the investigation was designed: (a) to compare reflex thresholds for pure tone(PT), octave band noise(OBN), and one-third octave band noise(TQBN); (b) to study middle ear muscle activity during a five minute exposure to these stimuli at 114 dB SPL; and (c) to compare middle ear muscle activity for stimuli of different frequencies. Eighteen subjects were divided into two groups. Group I subjects were exposed to a 700 Hz PT, to OBN with center frequency 500 Hz, and TOBN with center frequency 630 Hz; Group II subjects were exposed to a 1400 Hz PT, to OBN with center frequency 1000 Hz, and TOBN with center frequency 1250 Hz. A Madsen Electroacoustic Impedance Bridge and graphic recorder were used to record impedance changes during stimulation with the above stimuli. These impedance changes were assumed to reflect muscle activity. Thresholds for the acoustic reflex were determined using standard procedures. Analysis of results indicated muscle activity decreased progressively during stimulation. Reflex decay was significantly greater for stimulation with PT than for stimulation with OBN(Groups I and II) and TOBN(Group II). It was noted that reflex decay was less during stimulation with a 700 Hz PT than during stimulation with a 1400 Hz PT. Finally, it was observed that reflex thresholds were higher for PT than for OBN and TOBN. Decrease in muscle activity during acoustic stimulation was discussed in terms of adaptation and possibly central mechanisms; the characteristics of the stimuli were compared and discussed, as a possible explanation for differences in results obtained for tones and noise. / Medicine, Faculty of / Audiology and Speech Sciences, School of / Graduate

O objetivo deste estudo foi a validação da medida de limiar anaeróbio com o teste escalonado intermitente de 20 m de ida-e-volta em quadra, comparando-o com teste escalonado em esteira e com o máximo “steady state” de lactato (MLSS) em teste retangular simulado, em jogadores de Futsal. Para isso, nove jogadores de Futsal (16,8 ± 1,27 anos) realizaram um teste incremental em esteira (protocolo de HECK, 1985) para determinação da velocidade de 3,5 mmol.l-1 de lactato (V3,5Heck). Também para determinação da V3,5 (V3,5leger), os atletas realizaram teste progressivo de 20 m de ida-e-volta, com velocidade inicial de 8,5 km.h-1, com incremento de 1 km.h-1 a cada três minutos. Após a determinação da V3,5leger, os atletas retornaram à quadra e realizaram (pelo menos) três testes para a determinação do MLSS. O MLSS foi determinado através de corrida intermitente (20 m de ida-e-volta) e definido como a maior velocidade em que o lactato sanguíneo não aumentou mais que 1 mmol.l-1 de lactato entre o 10 e 30 minutos com velocidade constante. As velocidades correspondentes à V3,5leger e MLSS tiveram correlação de r = 0,86. O teste de comparações múltiplas TURKEY TEST detectou que existe diferença (p<0,05) entre as médias de intensidade de MLSS e V3,5Heck e entre V3,5Heck e V3,5leger. Já entre V3,5leger e MLSS, o teste não detectou diferença. A correlação entre a F.C. no V3,5leger e o MLSS foi de r = 0,70. O teste de comparações múltiplas TURKEY TEST detectou que existe diferença (p<0,05) entre as médias de F.C. entre V3,5leger e MLSS e entre V3,5Heck e MLSS. Já entre V3,5leger e V3,5Heck, o teste não detectou diferença. Portanto, nós concluímos que a V3,5leger é um instrumento válido para se estimar o MLSS em jogadores de Futsal. / The objective of this study was to investigate the validity of the anaerobic threshold in the 20 m shuttle run test in the determination of the maximal lactate steady state (MLSS) in Futsal players. Nine male futsal players (16,8 ± 1.27 years) performed an incremental treadmill test for the determination of the velocity corresponding of 3.5 mmol.l-1 of lactate (HECK et alii, 1985) (V3.5Heck). Also for the determination of the V3.5 (V3.5leger), the Futsal players performed the 20 m shuttle run test, with the initial running speed of 8.5 km.h-1 and increment of 1 km.h-1 each three minutes. After the determination of the V3.5 the athletes performed at least three tests to determine the MLSS. The MLSS was determined through intermittent running (20 m shuttle run) and defined as the highest velocity at which blood lactate did not increase by more than 1 mmol.l-1 between the minutes 10 and 30 of the constant velocity runs. There was a significant correlation between the velocities of V3.5leger and MLSS (r = 0.86). Analysis of variance revealed significant difference (p<0.05) between the intensities of the MLSS and V3.5Heck and between V3.5Heck e V3.5leger, but the analysis did not reveal difference between V3.5leger and the MLSS. The correlation between the heart frequency (F.C.) in the V3.5 Leger and MLSS was r=0.70. The analysis of variance revealed significant differences (p<0.05) between F.C. in V3.5leger and MLSS and between V3.5Heck and MLSS. The analysis did not revealed differences between V3.5leger and V3.5Heck. We conclude that OBLA can be utilized in Futsal players to estimate the MLSS.

The advancement of wireless technology has led to an increase in the employment of wireless sensor networks (WSNs). Traditionally, WSNs are powered by batteries. However, the high power consump- tion and the need to change the batteries regularly has made these networks costly to maintain. The nodes in the WSNs are increasingly strained as power consumption increases and the batteries are depleted faster. This has consequently decreased the overall lifetime of the WSNs. Although many energy-conserving techniques exist, for example energy-efficient medium access control and energy-efficient routing protocols, energy consumption remains one of the significant constraints in the development of WSNs. A natural solution to this constraint is harvesting energy from the environment. However, unlike conventional energy, energy harvested from the environment is random in nature, making it challenging to realise energy-harvesting transmission schemes. Although energy harvesting might be considered a solution to many problems, it brings about new challenges with regard to the usage and management of the energy harvested. Some of these challenges include uneven consumption of power in the network, resulting in dead nodes in some portion of the network and the batteries used in the network are being affected negatively by the energy usage; they may consequently sustain the nodes for long or short periods. To analyse the usage and consumption of energy, a number of techniques have been proposed, namely; information theory, game theory and queueing theory. By this time, the performance of the sensor nodes in WSNs has been analysed making use of a queueing-theoretic model for each sensor. The aforementioned model inadequately expresses the physical constraints, namely, the energy drawing process and the finite battery capacity. This research focuses on developing a model that captures the harvesting, accumulation and dissipation of energy, utilising queueing theory. A rechargeable battery with a finite storage capacity will be used. To ensure that the battery does not lose its capability to store charge after being recharged repeatedly, the leaky bucket model is proposed to check the network data flow as the harvested energy in the WSN is analysed. To capture real-world WSNs with energy harvesting in which there is energy leakage, the energy- harvesting sensor node performance is analysed with two assumptions: data transmission and energy leakage occurring and the token buffer being subjected to a threshold. The system had finite buffers for the data and energy. To make it possible to have some influence over the system performance measures a threshold is imposed on the token buffer. Four models are developed: a basic model, a basic model with leakage incorporated, a basic model with leakage and priority incorporated and a basic model with leakage, priority and threshold incorporated. The developed models are simulated and results for the performance measures are obtained. / Dissertation (MEng (Computer Engineering))--University of Pretoria, 2021. / BWMC, NRF / Electrical, Electronic and Computer Engineering / MEng (Computer Engineering) / Unrestricted