Three stages of research were carried out to investigate the use of the self-paced visual occlusion technique, and to model visual information sampling. Stage 1. A low-fidelity driving simulator study was carried out to investigate the effect of glance duration, a key parameter of the self-paced occlusion technique, on occlusion times. Results from this experiment, paired with analysis of data available from an on-road driving study, found an asymptotic relationship between the two variables. This finding has practical implications for establishing the appropriate glance duration in experimental studies that use self-paced visual occlusion. Stage 2. A model of visual information sampling was proposed, which incorporates elements of uncertainty development, subjective thresholds, and an awareness of past and current states of the system during occlusion. Using this modelling framework, average information sampling behaviour in occlusion studies can be analysed via mean occlusion times, and moment-by-moment responses to system output can be analysed via individual occlusion times. Analysis using the on-road driving data found that experienced drivers demonstrated a more complex and dynamic sampling strategy than inexperienced drivers. Stage 3. Findings from Stage 2 led to a simple monitoring experiment that investigated whether human operators are in fact capable of predicting system output when temporarily occluded. The platform was designed such that the dynamics of the system naturally facilitated predictions without making the monitoring task trivial. Results showed that participants were able to take predictive information into account in their sampling decisions, in addition to using the content of the information they observed from each visual sample.

Three stages of research were carried out to investigate the use of the self-paced visual occlusion technique, and to model visual information sampling. Stage 1. A low-fidelity driving simulator study was carried out to investigate the effect of glance duration, a key parameter of the self-paced occlusion technique, on occlusion times. Results from this experiment, paired with analysis of data available from an on-road driving study, found an asymptotic relationship between the two variables. This finding has practical implications for establishing the appropriate glance duration in experimental studies that use self-paced visual occlusion. Stage 2. A model of visual information sampling was proposed, which incorporates elements of uncertainty development, subjective thresholds, and an awareness of past and current states of the system during occlusion. Using this modelling framework, average information sampling behaviour in occlusion studies can be analysed via mean occlusion times, and moment-by-moment responses to system output can be analysed via individual occlusion times. Analysis using the on-road driving data found that experienced drivers demonstrated a more complex and dynamic sampling strategy than inexperienced drivers. Stage 3. Findings from Stage 2 led to a simple monitoring experiment that investigated whether human operators are in fact capable of predicting system output when temporarily occluded. The platform was designed such that the dynamics of the system naturally facilitated predictions without making the monitoring task trivial. Results showed that participants were able to take predictive information into account in their sampling decisions, in addition to using the content of the information they observed from each visual sample.

Background/Objective: Reperfusion injury is a serious consequence of blood flow reestablishment after myocardial infarction (MI) mediated by reactive oxygen species and neutrophilic cellular damage. Following MI, the left ventricle (LV) undergoes remodeling characterized by progressive wall thinning and cavity dilatation. Heme-Oxygenase-1 (HO-1) dependent decrease in oxidative stress may attenuate injury in part by inhibiting transcription factor NFκB-mediated inflammation. Hypothesis: I hypothesized that upregulation of HO-1 by hemin administration confers acute and chronic cardioprotection against I/R injury in rats and attenuates LV remodeling post-MI. I proposed the HO-1-dependent decrease in oxidative stress attenuates post-ischemic myocardial injury in part by inhibiting NFκB-mediated inflammation. Methods: Six week old male Wistar rats were randomly assigned to sham, vehicle, or hemin-treated groups. Vehicle and hemin were administered intraperitoneally once daily for 3 consecutive days prior to left anterior descending (LAD) coronary artery occlusion. Administration resumed 48 hours post-operatively and continued once every 3 days. Infarct size was determined by H&E histological analysis and fibrosis was quantified by Masson’s Trichrome staining. Transthoracic echocardiography was used to assess LV parameters and wall motion. Results: Hemin increased HO-1 expression, decreased infarct size and fibrosis, and attenuated LV remodeling in the short-term (4 days post-infarction). The decrease in infarct size and area of fibrosis in the hemin group was accompanied by a decrease in NFκB activity. No significant difference in infarct size and area of fibrosis between hemin and vehicle-treated groups was observed at 3 months. LV diameter and cardiac function did not differ significantly between the two groups at 3 months despite an attenuation of anterior wall thinning in the hemin group. Conclusion: HO-1 upregulation by hemin administration conferred acute cardioprotection and attenuated LV remodeling, possibly by inhibiting NFκB-mediated inflammation. However, chronic treatment with hemin did not prevent long-term post-infarction LV remodeling. It is possible that cardioprotection afforded by HO-1 upregulation is strong enough to curtail inflammation post-reperfusion and prevent LV remodeling acutely, but is not robust enough to protect the myocardium to the same degree in the long-term. Future research should focus on optimal HO-1 upregulation to attenuate long-term LV remodeling due to reperfusion injury. / Thesis (Master, Physiology) -- Queen's University, 2007-09-25 19:01:33.87

Thesis (M.S.)--University of Michigan, 1983.

Thesis (M.S.)--University of Michigan, Ann Arbor, 1975. / Typescript (photocopy). Includes bibliographical references (leaves 57-60). Also issued in print.

Thesis (M.S.)--University of Michigan, 2002. / Includes bibliographical references.

Thesis (M.S.)--University of Michigan, 1983.

Thesis (M.S.)--University of Michigan, Ann Arbor, 1975. / Typescript (photocopy). eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 57-60).

Thesis (Ph. D.)--University of Washington, 2005. / Vita. Includes bibliographical references (leaves 121-133).

Orientador: Ana Carolina Pero Vizoto / Resumo: O tratamento reabilitador com próteses totais convencionais tem como objetivos restabelecer a mastigação, a fonética e a deglutição, assim como proporcionar estética e conforto. O sucesso desse tratamento deve combinar a satisfação do paciente com etapas clínicas e laboratoriais criteriosas e bem executadas, principalmente as que envolvem os procedimentos de moldagem, registro das relações intermaxilares e escolha do esquema oclusal. Atualmente, o esquema oclusal mais difundido em prótese total é a oclusão balanceada bilateral (OBB). No entanto, a literatura aponta que a desoclusão pelos caninos (DC) é uma alternativa viável na confecção de próteses totais convencionais. Estudos randomizados controlados para verificar o efeito da guia de desoclusão nas variáveis relacionadas à mastigação ainda são necessários. O objetivo deste estudo cross-over foi analisar a influência da guia de desoclusão no desempenho e habilidade mastigatória de usuários de próteses totais convencionais. Foram convidados a participar do estudo indivíduos desdentados totais, do sexo feminino, que receberam tratamento com próteses totais convencionais, de acordo com os princípios clínicos e laboratoriais preconizados pela Disciplina de Prótese Total da Faculdade de Odontologia de Araraquara (UNESP) (n=50). Após o período de adaptação com as novas próteses (fase pré-teste), os participantes foram divididos em duas sequências de estudo onde, em períodos alternados e sequenciais de 30 dias cada, foram designa... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The rehabilitation treatment with conventional complete dentures aims restoring chewing, phonetics and swallowing, as well providing esthetics and comfort. The success of this treatment should combine patient satisfaction with clinical and laboratorial stages wellexecuted, especially those involving molding procedures, record of intermaxillary relationships and choice of occlusal scheme. Currently, the most widespread occlusal scheme in complete dentures is bilateral balanced occlusion (BBO). However, the literature indicates that canines guidance (CG) it is a viable alternative in the production of conventional complete dentures. Randomized controlled trials to verify the effect of the disocclusion guidance on variables related to chew are still necessary. The objective of this cross-over study was to analyze the influence of disocclusion guidance on masticatory performance and ability in wearers of complete dentures. Total edentulous individuals, female, who received treatment with conventional complete dentures, were invited to participate in this study according to the clinical and laboratory principles recommended by Araraquara Dental School (UNESP) (n = 50). After the period of adaptation with the new dentures (pre-test phase), the participants were divided into two sequences of study, where, in alternating and sequential periods of 30 days each, they were assigned to the two types of protocols proposed: Sequence 1: bilateral balanced occlusion - BBO, followed by canines guidance - CG; Sequence 2: canines guidance - CG, followed by bilateral balanced occlusion - BBO. The evaluations of masticatory performance and masticatory ability were carried out, respectively, using the sieves method and the application of a specific questionnaire based on a visual analogue scale (VAS), at different times: 30 days after the pre-test phase (Assesment 1), and 60 days after the pre-test phase...(Complete abstract electronic access below) / Mestre