The purpose of the present study was to explore the relationship between internalized racism, stereotype threat, self-handicapping, test performance, and cardiovascular responses in Black individuals. Stereotype threat, or apprehension about confirming a negative stereotype, has been shown to lead to self-handicapping, poor academic performance, as well as increased cardiovascular reactivity. Internalized racism, or the acceptance of negative stereotypes about one's group, is a factor that may moderate these relationships. One-hundred nine (84% female, 16% male) Black undergraduates participated in a laboratory study. Half of the participants were put in a stereotype-threatened condition and the other half were in a neutral condition. The participants were permitted unlimited time in which to practice for a verbal test and then were tested on their verbal ability while their blood pressure was monitored. Results indicated that internalized racism moderates the relationship between stereotype threat and systolic blood pressure, but not diastolic blood pressure or heart rate. However, the moderating effect of internalized racism in the relationship between stereotype threat and self-handicapping or test performance was not significant. It seems that individuals who do not accept the negative stereotypes about Blacks as a group experienced increased systolic blood pressure responses in stereotype-threatened situations compared to Black individuals who do accept the negative stereotypes. The implication is that Black individuals who challenge negative stereotypes will feel more stress when placed in situations where they are at risk of confirming those negative stereotypes. This study provides insight into reasons for the variability of cardiovascular disease among Black Americans, who typically experience a higher incidence overall compared to other ethnic groups.

Healthcare practitioners, whom perform accurate sub-maximal exercise tests in healthy individuals, need to understand the physiological demands and normal cardiovascular (CV) responses with exercise. Exercise testing delivers valid information about the physiological systems of individuals that may identify healthy individuals at risk of developing future cardiovascular disease (CVD). Exercise is a common way to assess physiological stress experienced by an individual, because CV abnormalities that are not present at rest, can be elicited during exercise testing and be used to determine the adequacy of cardiac function. Cardiovascular markers like, resting heart rate (HR) and systolic blood pressure (SBP) have been used as simple non-invasive and useful biomarkers of the fundamental status of blood circulation and the CV system in healthy individuals. Studies have contributed to exercise under sub-maximal and maximal stress testing. Modern- day literature lacks information on the safe HR and SBP responses to an increase in workload during a sub-maximal exercise protocol in healthy individuals. Consequently, the first purpose of this study was to identify the current evidence in the literature on CV response during a sub-maximal incremental exercise protocol. Different protocols and modalities contribute to various CV responses over a wide age group and gender. Heart rate and SBP increases in a linear fashion with an increase in workload, irrespective of protocol and modality. The amount of this increase, or the response of these markers, is still a grey area in the literature, especially in healthy individuals. The second purpose of this study was to analyse the HR and SBP response in healthy adults during a sub-maximal incremental exercise test, with an increase in workload (watt). The systematic review found mean changes from baseline for HR and SBP to be 75.7% and 63.5% respectively, on bicycle protocols (N = 3). The treadmill protocols (N = 2) found similar mean changes from baseline of 113.3% for HR and 36.1% for SBP. Descriptive measures as well as Linear regression analyses were performed, using Generalised estimated equations (GEE). An independent t-test was used to compare the males with the female participants: HR and SBP response to an increase in workload (watt). GEE adjustments were made for age, body mass index (BMI) and workload (watt). Significant difference levels were set at p ≤ 0.05. The present once-off subject availability results revealed that male subjects were heavier and taller than their female counterparts (p ≤ 0.05). They also had a noteworthy higher SBPrest, as well as BMI (p ≤ 0.05). The results from the GEE analyses we presented prediction equation, with all variables significant, except for the BMI (p = 0.972 females; p = 0.169 males). In conclusion, the literature review indicated a lack of information on the HR and SBP response with workload in healthy adults. It is advised that further research is needed to test the prediction equations in healthy individuals to determine the validity and reliability. They need to be tested in a controlled clinical environment, where the participants are monitored more thoroughly. By putting these predicted equations to the test, healthcare practitioners will be able to identify an exaggerated HR and SBP response with an increase in workload. If the individual’s response is exaggerated, the healthcare practitioner can intervene to prevent future cardiovascular events. / Thesis (MSc (Biokinetics))--North-West University, Potchefstroom Campus, 2013

Healthcare practitioners, whom perform accurate sub-maximal exercise tests in healthy individuals, need to understand the physiological demands and normal cardiovascular (CV) responses with exercise. Exercise testing delivers valid information about the physiological systems of individuals that may identify healthy individuals at risk of developing future cardiovascular disease (CVD). Exercise is a common way to assess physiological stress experienced by an individual, because CV abnormalities that are not present at rest, can be elicited during exercise testing and be used to determine the adequacy of cardiac function. Cardiovascular markers like, resting heart rate (HR) and systolic blood pressure (SBP) have been used as simple non-invasive and useful biomarkers of the fundamental status of blood circulation and the CV system in healthy individuals. Studies have contributed to exercise under sub-maximal and maximal stress testing. Modern- day literature lacks information on the safe HR and SBP responses to an increase in workload during a sub-maximal exercise protocol in healthy individuals. Consequently, the first purpose of this study was to identify the current evidence in the literature on CV response during a sub-maximal incremental exercise protocol. Different protocols and modalities contribute to various CV responses over a wide age group and gender. Heart rate and SBP increases in a linear fashion with an increase in workload, irrespective of protocol and modality. The amount of this increase, or the response of these markers, is still a grey area in the literature, especially in healthy individuals. The second purpose of this study was to analyse the HR and SBP response in healthy adults during a sub-maximal incremental exercise test, with an increase in workload (watt). The systematic review found mean changes from baseline for HR and SBP to be 75.7% and 63.5% respectively, on bicycle protocols (N = 3). The treadmill protocols (N = 2) found similar mean changes from baseline of 113.3% for HR and 36.1% for SBP. Descriptive measures as well as Linear regression analyses were performed, using Generalised estimated equations (GEE). An independent t-test was used to compare the males with the female participants: HR and SBP response to an increase in workload (watt). GEE adjustments were made for age, body mass index (BMI) and workload (watt). Significant difference levels were set at p ≤ 0.05. The present once-off subject availability results revealed that male subjects were heavier and taller than their female counterparts (p ≤ 0.05). They also had a noteworthy higher SBPrest, as well as BMI (p ≤ 0.05). The results from the GEE analyses we presented prediction equation, with all variables significant, except for the BMI (p = 0.972 females; p = 0.169 males). In conclusion, the literature review indicated a lack of information on the HR and SBP response with workload in healthy adults. It is advised that further research is needed to test the prediction equations in healthy individuals to determine the validity and reliability. They need to be tested in a controlled clinical environment, where the participants are monitored more thoroughly. By putting these predicted equations to the test, healthcare practitioners will be able to identify an exaggerated HR and SBP response with an increase in workload. If the individual’s response is exaggerated, the healthcare practitioner can intervene to prevent future cardiovascular events. / Thesis (MSc (Biokinetics))--North-West University, Potchefstroom Campus, 2013

Previously, at Brunel University, two computer programs had been developed to facilitate the analysis of the diastolic material properties of the human left ventricle. These two computer programs consisted of; a finite element program, "XL1", which ran upon a Cray-1S/1000 and a post-processor and pre-processor, "HEART", which ran upon the Multics computer system. The computer program "HEART" produced the finite element model, which was then solved by "XL 1", and it also allowed for plotting the results in graphical form, The patient data was supplied by the Royal Brompton Hospital in the form of digitised cine-angiographic X-ray data plus pressure readings. The first stage was to transfer the two separate computer programs "HEART" and "XL 1" to the Sun Workstation system. The two programs were then combined to form a single package which can be used for the automated analysis of the patient data. An investigation into the effect that the elastic modulus ratio has upon the deformation of the left ventricle during diastole was performed. It was found that the effect is quite small and that using this parameter to match overall shape deformation would be extremely sensitive to the accuracy of the initial data. The main part of this work was the implementation of active cardiac contraction, by means of a thermal stress analogy, into the finite element program. This allows the systolic part of the cardiac cycle to be analysed. The analysis of the factors that affect cardiac contraction, including the material properties and boundary conditions was performed. This model was also used to investigate the effect that conditions such as ischaemia and the formation of scar tissue have upon the systolic left ventricle. The use of the thermal stressing analogy for cardiac contraction was demonstrated to mirror global and local deformation when applied to a realistic ventricular geometry.

Title: What explains variability in blood pressure readings? Multilevel analysis of data from 8,731 older adults in 20 Ontario Communities Objectives: Despite universal healthcare and drug coverage for adults aged 65 and over in Ontario, hypertension, a treatable condition, remains uncontrolled among many older adults. Moreover, there are geographic disparities in blood pressure and hypertension within and across Canadian provinces and territories. Using baseline data collected on 8,731 older adults participating in the Cardiovascular Health Awareness Program (CHAP) in 20 randomly selected Ontario communities, we investigated associations between systolic blood pressure (SBP) and individual- and community-level characteristics, controlling for self-reported use of blood pressure medications. Method: Older adults were recruited via invitation by local family physicians, public advertising and word of mouth to attend community pharmacy sessions. During the sessions, trained older adult volunteers assisted participants to complete a cardiovascular disease risk factor questionnaire and blood pressure assessments using an automated blood pressure measuring device. The Postal Code Conversion File Plus was used to confirm residence within one of the 20 study communities. A multilevel linear regression analysis with participants nested within communities was used to determine which individual- and/or community-level characteristics were associated with measured systolic blood pressure level controlling for self-reported use of blood pressure medication. Results: 4,706 participants (53.9%) reported the use of blood pressure medication. Mean systolic blood pressure (SBP) levels varied among the 20 communities from 128.1 mmHg to 134.7 mmHg for participants not using blood pressure medication and from 131.9 mmHg to 139.0 mmHg for participants using blood pressure medication. The intraclass correlation coefficients were very small: less than 0.2% of the total variance was between communities. Among participants not using blood pressure medication, SBP was associated with the following individual- level characteristics: age, sex, body mass index , smoking, physical activity, stress, fruit/vegetable intake, and alcohol consumption and the following community-level characteristics: community size, community growth and the Rurality Index. Among participants using blood pressure medication, SBP was associated with the following individual-level characteristics: age, sex, body mass index, diabetes, fruit/vegetable intake, alcohol intake and one community-level characteristic: community size. The significance and magnitude of these associations were modified by the use of blood pressure medication. Conclusion: The majority of the variability in blood pressure occurs at the individual-level. There are specific individual- and community-level factors that explain variability in blood pressure readings among communities. These results can be used to inform health promotion strategies to decrease mean levels of blood pressure among older adults.

abstract: This thesis report aims at introducing the background of QR decomposition and its application. QR decomposition using Givens rotations is a efficient method to prevent directly matrix inverse in solving least square minimization problem, which is a typical approach for weight calculation in adaptive beamforming. Furthermore, this thesis introduces Givens rotations algorithm and two general VLSI (very large scale integrated circuit) architectures namely triangular systolic array and linear systolic array for numerically QR decomposition. To fulfill the goal, a 4 input channels triangular systolic array with 16 bits fixed-point format and a 5 input channels linear systolic array are implemented on FPGA (Field programmable gate array). The final result shows that the estimated clock frequencies of 65 MHz and 135 MHz on post-place and route static timing report could be achieved using Xilinx Virtex 6 xc6vlx240t chip. Meanwhile, this report proposes a new method to test the dynamic range of QR-D. The dynamic range of the both architectures can be achieved around 110dB. / Dissertation/Thesis / M.S. Electrical Engineering 2014

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-04-05T14:47:50Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação_Figueiroa(versao_final).pdf: 2779464 bytes, checksum: bec03362367d058faa9ed8c36d09b5f8 (MD5) / Made available in DSpace on 2016-04-05T14:47:50Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação_Figueiroa(versao_final).pdf: 2779464 bytes, checksum: bec03362367d058faa9ed8c36d09b5f8 (MD5) Previous issue date: 2015-08-17 / A partir da revelação da estrutura em dupla-hélice do DNA, em 1953, foi aberto o caminho para a compreensão dos mecanismos que codificam as instruções de construção e desenvolvimento das células dos seres vivos. A nova geração de sequenciadores (NGS) têm produzido gigantescos volumes de dados nos Bancos de Dados biológicos cujas informações podem demandar uma intensa atividade computacional em sua compilação. Entretanto, o desempenho das ferramentas empregadas na Biologia Computacional não tem evoluído na mesma taxa de crescimento desses bancos, podendo impor restrições aos avanços neste campo de pesquisa. Uma das principais técnicas usadas é o alinhamento de sequências que, a partir da identificação de similaridades, possibilitam a análise de regiões conservadas em sequências homólogas, servem como ponto de partida no estudo de estruturas secundárias de proteínas e de construção de àrvores filogenéticas, entre outros. Como os algoritmos exatos de alinhamento possuem complexidade quadrática no tempo e no espaço, o custo computacional poderá ser elevado demandando estratégias de aceleração. Neste contexto, a Computação de Alto Desempenho (HPC), estruturada em Supercomputadores e Clusters, tem sido, empregada. No entanto, o investimento inicial e os requisitos de manutenção, espaço físico, refrigeração, além do consumo de energia, podem representar custos significativos. As arquiteturas paralelas híbridas baseadas na ação conjunta de PCs e dispositivos aceleradores como chips VLSI, GPGPUs e FPGAs, surgiram como alternativas mais acessíveis, apresentando resultados promissores. O projeto descrito nesta dissertação tem por objetivo a aceleração do algoritmo de alinhamento-ótimo global, conhecido como Needleman-Wunsch, a partir de uma plataforma híbrida baseada em um PC (host) e um FPGA. A aceleração ocorre a partir da exploração das possibilidades de paralelismo oferecidas pelo algoritmo e sua implementação em hardware. A arquitetura desenvolvida é baseada num Array Sistólico Linear apresentando elevado desempenho e boa escalabilidade. / From the revelation of the structure in double-helix of Deoxyribonucleic Acid (DNA) by James D. Watson and Francis H. C. Crick, in 1953, it opened the way for the understanding of the mechanismis that encoding the building instructions and development of cells of living beings. The DNA sequencing is one of the first steps in this process. The new generation of sequencers (NGS) have produced massive amounts of data on biological databases whose information may require intense computational activity in your compilation. However, the performance of the tools employed in Computational Biology has not evolved at the same rate of growth of these banks, may impose restrictions on advances in this research field. One of the primary techniques used is the sequence alignment that from the identification of similarities, enable the analysis of conserved regions of homologous sequences, serve as the starting point in the study of protein secondary structures and the construction of phylogenetic trees, among others. As the exact alignment algorithms have quadratic complexity in time and space, the computational cost can be high demanding acceleration strategies. In this context, the High Performance Computing (HPC), structured in supercomputers and clusters, has been employed. However, the initial investment and maintenance requirements, floor space, cooling, in addition to energy consumption, may represent significant costs. The hybrid parallel architectures based on joint action of PCs and devices accelerators as VLSI chips, GPGPUs and FPGAs, have emerged as more affordable alternatives, with promising results. The project described in this dissertation aims at accelerating the global optimal-alignment algorithm, known as Needleman-Wunsch, from a hybrid platform based on a PC, that acts as host, and an FPGA. The acceleration occurs through exploration of the parallelism opportunities offered by the algorithm and implemented in hardware. In this, an architecture based on a Linear Systolic Array offers high performance and high scalability.

Instruction systolic arrays (ISAs) provide a programmable high performance hardware for specific computationally intensive applications. Typically, such an array is connected to a sequential host, thus operating like a coprocessor which solves only the computationally intensive tasks within a global application. The ISA model is a mesh connected processor grid, which combines the advantages of special purpose systolic arrays with the flexible programmability of general purpose machines. The subject of this thesis is the analysis, design, and implementation of several special purpose algorithms and subroutines on the ISA that take advantage of the special features of the systolic information flow. The ability of ISAs to perform parallel prefix computations in an extremely efficient way is exploited as a key-operation to derive efficiency as well as local operations within each processor. Therefore, given sequential algorithms has to be decomposed in simple building blocks of parallel prefix computations and parallel local operations. To modify sequential algorithms for a parallelisation several techniques are introduced in this thesis, e. g. swapping of loops in the sequential algorithm, shearing of data, and appropriate mapping of input data onto the processor array It is demonstrated how these techniques can be exploited to derive efficient ISA algorithms for several computationally intensive applications. These include cryptographic applications (e. g. arithmetic operations on long operands, RSA encryption, RSA key generation) and image processing applications (e. g. convolution, Wavelet Transform, morphological operators, median filter, Fourier Transform, Hough Transform, Morphological Hough Transform, and tomographic image reconstruction). Their implementation on Systola 1024 - the first commercial parallel computer with the ISA architecture - shows that the concept of the ISA is very suitable for these applications and results in significant run time savings. The results of this thesis emphases the suitability of the ISA concept as an accelerator for computationally intensive applications in the areas of cryptography and image processing. This might lead research towards further high-speed low cost systems based on ISA hardware.

Title: What explains variability in blood pressure readings? Multilevel analysis of data from 8,731 older adults in 20 Ontario Communities Objectives: Despite universal healthcare and drug coverage for adults aged 65 and over in Ontario, hypertension, a treatable condition, remains uncontrolled among many older adults. Moreover, there are geographic disparities in blood pressure and hypertension within and across Canadian provinces and territories. Using baseline data collected on 8,731 older adults participating in the Cardiovascular Health Awareness Program (CHAP) in 20 randomly selected Ontario communities, we investigated associations between systolic blood pressure (SBP) and individual- and community-level characteristics, controlling for self-reported use of blood pressure medications. Method: Older adults were recruited via invitation by local family physicians, public advertising and word of mouth to attend community pharmacy sessions. During the sessions, trained older adult volunteers assisted participants to complete a cardiovascular disease risk factor questionnaire and blood pressure assessments using an automated blood pressure measuring device. The Postal Code Conversion File Plus was used to confirm residence within one of the 20 study communities. A multilevel linear regression analysis with participants nested within communities was used to determine which individual- and/or community-level characteristics were associated with measured systolic blood pressure level controlling for self-reported use of blood pressure medication. Results: 4,706 participants (53.9%) reported the use of blood pressure medication. Mean systolic blood pressure (SBP) levels varied among the 20 communities from 128.1 mmHg to 134.7 mmHg for participants not using blood pressure medication and from 131.9 mmHg to 139.0 mmHg for participants using blood pressure medication. The intraclass correlation coefficients were very small: less than 0.2% of the total variance was between communities. Among participants not using blood pressure medication, SBP was associated with the following individual- level characteristics: age, sex, body mass index , smoking, physical activity, stress, fruit/vegetable intake, and alcohol consumption and the following community-level characteristics: community size, community growth and the Rurality Index. Among participants using blood pressure medication, SBP was associated with the following individual-level characteristics: age, sex, body mass index, diabetes, fruit/vegetable intake, alcohol intake and one community-level characteristic: community size. The significance and magnitude of these associations were modified by the use of blood pressure medication. Conclusion: The majority of the variability in blood pressure occurs at the individual-level. There are specific individual- and community-level factors that explain variability in blood pressure readings among communities. These results can be used to inform health promotion strategies to decrease mean levels of blood pressure among older adults.

Orientador: Paulo Sergio Patto dos Santos / Resumo: A nalbufina é um opioide agonista-antagonista com propriedades analgésicas adequadas e poucos efeitos depressores no sistema respiratório. Sua utilização na medicina veterinária é limitada pois muitos veterinários desconhecem suas vantagens. Além disso, seus efeitos na função cardíaca são pouco estudados. Portanto, com o estudo objetivou-se avaliar os efeitos da infusão contínua de nalbufina na função sistólica e diastólica do ventrículo esquerdo em cães saudáveis anestesiados com sevofluorano. Foram utilizados dezoito cães fêmeas de diversas raças ou sem raça definida, com idade média de 2 ± 1 anos e peso médio de 9,9 ± 3,8 kg. Os cães foram aleatoriamente submetidos a dois grupos denominados: nalbufina (GN) e controle (GC), com nove animais para cada grupo. Os animais foram induzidos e mantidos sob anestesia com sevofluorano (2V%). No GN foi administrado bolus intravenoso de nalbufina (0,3 mg/kg), seguido de infusão continua (0,4 mg/kg/h). O GC recebeu solução salina (NaCl 0,9%), em volumes idênticos em bolus e infusão ao GN. As variáveis ecocardiográficas de função sistólica e diastólica e os parâmetros hemodinâmicas foram determinadas no momento basal (antes do bolus) e 20, 40, 60 e 80 minutos após o início da infusão contínua. Não houve diferença entre os grupos para os parâmetros de função sistólica e diastólica ventricular esquerda derivados da ecocardiografia convencional e speckle tracking bidimensional. Do mesmo modo, as variáveis hemodinâmicas não apresentaram dife... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Nalbuphine is an agonist-antagonist opioid with adequate analgesic properties and few depressant effects on the respiratory system. Its use in veterinary medicine is limited due to the unknown of its effects on cardiac function. The aim of this study was to assess the effects of a continuous rate infusion (CRI) of nalbuphine on left ventricular systolic and diastolic function of healthy sevoflurane-anesthetized dogs. Were used eighteen mixed-breed bitches ageging 2 ± 1 years and weighing 9.9 ± 3.8 kg. Dogs were randomly assigned to one of two groups: nalbuphine (GN, n=9); and control (GC, n=9). Anesthesia was induced and maintained with sevoflurane (2V%) followed by an intravenous (IV) bolus of nalbuphine (0.3 mg/kg) or 0.9% NaCl at equal volume, then CRI of nalbuphine (0.4 mg/kg/h) or 0.9% NaCl at equal infusion rate. Echocardiographic and hemodynamic variables were determined at baseline and 20, 40, 60 and 80 minutes following start of CRI. No differences were found between groups for left ventricular systolic and diastolic variables obtained through conventional echocardiography and two-dimensional speckle tracking. Likewise, hemodynamic variables did not differ between groups. The E′/A′ ratio significantly increased at 20 minutes compared to baseline only in GN. Nalbuphine given at a CRI does not influence left ventricular systolic and diastolic function in healthy sevoflurane-anesthetized dogs. / Doutor