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Full-Text Articles in Life Sciences

A Hybrid Visual Control Scheme To Assist The Visually Impaired With Guided Reaching Tasks, Duane Jacques Nov 2013

A Hybrid Visual Control Scheme To Assist The Visually Impaired With Guided Reaching Tasks, Duane Jacques

Electronic Thesis and Dissertation Repository

In recent years, numerous researchers have been working towards adapting technology developed for robotic control to use in the creation of high-technology assistive devices for the visually impaired. These types of devices have been proven to help visually impaired people live with a greater degree of confidence and independence. However, most prior work has focused primarily on a single problem from mobile robotics, namely navigation in an unknown environment. In this work we address the issue of the design and performance of an assistive device application to aid the visually-impaired with a guided reaching task. The device follows an eye-in-hand, …


A Quantitative Emg Assessment Of Motor Unit Recruitment In Patients With Ulnar Neuropathy, Kayla N. Ryan Sep 2013

A Quantitative Emg Assessment Of Motor Unit Recruitment In Patients With Ulnar Neuropathy, Kayla N. Ryan

Electronic Thesis and Dissertation Repository

The aim of the current study was to assess the test – retest reliability of motor unit firing rates with the use of decomposition based quantitative electromyography, and to quantify motor unit firing rates in the first dorsal interosseous of patients with ulnar neuropathy. 8 healthy subjects (mean age 35 ± 10 years) and 8 patients (mean age 48 ± 10 years) with ulnar neuropathy participated in the study. Following the acquisition of a maximum M wave, needle and surface detected EMGs were collected simultaneously during 30-second contractions performed at threshold (1-2% maximum voluntary contraction (MVC)) and 10% MVC- RMS …


A Six Week Modified Sprint Interval Training Program Incorporating Extended Exercise Bouts Does Not Increase Maximal Cardiac Output, Alan R. Smith Sep 2013

A Six Week Modified Sprint Interval Training Program Incorporating Extended Exercise Bouts Does Not Increase Maximal Cardiac Output, Alan R. Smith

Electronic Thesis and Dissertation Repository

Sprint interval training (SIT) improves maximal oxygen uptake (V̇O2max) and exercise performance but not maximal cardiac output (Q̇max). The brevity of typical SIT bouts (30-seconds) might hinder improvements in Q̇max. The purpose of this study was to determine whether extended duration SIT (up to 45 second bouts) improves Q̇max. Pre-/Post-SIT (or control) V̇O2max, Q̇max, maximum stroke volume (SVmax), maximum heart rate, arterial-mixed venous oxygen difference, and 5-minute run distance were measured. SIT progressed from 4x30s to 7x45s “all-out” efforts (4 min recovery) over 6 wk (3x/wk) …


Electromechanical Delay Of The Dorsiflexors In Young And Old Women, In H. Choi Sep 2013

Electromechanical Delay Of The Dorsiflexors In Young And Old Women, In H. Choi

Electronic Thesis and Dissertation Repository

PURPOSE: The aim of the current study was to examine the effect on electromechanical delay (EMD) in the dorsiflexors of young and old women during maximal isometric voluntary and electrically evoked contractions, and after a bout of lengthening contractions. METHODS: Nine young (25.1±1.3 years) and nine old (68.3±6.1 years) women performed baseline isometric contractions with evoked twitches followed by a series of dynamic lengthening contractions using a Biodex multi-joint dynamometer. Maximal isometric voluntary and evoked contractions were measured to assess EMD. Time points were recorded at baseline, mid-point of the intervention, post-task termination, and during recovery at 0.5, 2, 10, …


The Effect Of Low And High Carbohydrate Diets On Pulmonary Oxygen Uptake And Muscle Deoxygenation Kinetics During Exercise Transitions Into The Heavy-Intensity Domain, John Leckie Aug 2013

The Effect Of Low And High Carbohydrate Diets On Pulmonary Oxygen Uptake And Muscle Deoxygenation Kinetics During Exercise Transitions Into The Heavy-Intensity Domain, John Leckie

Electronic Thesis and Dissertation Repository

The purpose of this study was to determine the effects of a high carbohydrate (HCHO) and low carbohydrate (LCHO) diet on the adjustment of pulmonary oxygen (O2) uptake ( ) and muscle deoxygenation ([HHb]) during transitions to heavy intensity exercise. Young, healthy, male subjects aged (24+/-3) underwent a 4 day LCHO followed immediately by a 4 day HCHO diet, with each diet preceded by a glycogen depletion protocol. This protocol was designed to alter PDH activity. Subjects completed 3 step transitions to a work rate corresponding to 35% of the difference between their lactate threshold and peak for …


An Autoethnographical Tapestry Of Feminist Reflection On My Journey Of A Fitness Model Physique, Stephanie A. Paplinskie Aug 2013

An Autoethnographical Tapestry Of Feminist Reflection On My Journey Of A Fitness Model Physique, Stephanie A. Paplinskie

Electronic Thesis and Dissertation Repository

Weight training and fitness competitions are increasingly popular activities for many women seeking an aesthetically fit body. This thesis entails a critical reflection of the various factors surrounding my personal decision to partake in body sculpting, examining how these factors parallel the experience of other women in the fitness industry. Using a feminist theoretical framework and autoethnography, a history of feminist theory is incorporated to demonstrate some of the various perspectives surrounding women bodies. Two challenges for women are discussed in this paper: i) the fear of fat, and how it is connected to a woman’s initial decision to attend …


Adjustment Of Pulmonary O2 Uptake, Muscle Deoxygenation And Metabolism During Moderate-Intensity Exercise Transitions Initiated From Low And Elevated Baseline Metabolic Rates, Joshua P. Nederveen Aug 2013

Adjustment Of Pulmonary O2 Uptake, Muscle Deoxygenation And Metabolism During Moderate-Intensity Exercise Transitions Initiated From Low And Elevated Baseline Metabolic Rates, Joshua P. Nederveen

Electronic Thesis and Dissertation Repository

When instantaneous step-wise transitions within the moderate intensity domain are initiated from elevated metabolic rates, the rate of pulmonary oxygen uptake (V̇O2p) adjustment is slowed, and the V̇O2p gain (ΔV̇O2p /ΔWR) is greater. This study sought to determine the relationship between V̇O2p kinetics and metabolic activity and energy status during step transitions from low and elevated metabolic rates within the moderate intensity domain. Ten young men completed six double-step constant load cycling bouts, consisting of step-wise transitions from 20 W to 45% θL and 45% θL [lower step (LS)] to 90% θL …


Role Of Adenylyl Cyclase S674 In Central And Forearm Vasomotor Control, James Corkal Aug 2013

Role Of Adenylyl Cyclase S674 In Central And Forearm Vasomotor Control, James Corkal

Electronic Thesis and Dissertation Repository

This study examined the cardiac and vasomotor responses to submaximal handgrip exercise and beta-adrenergic control in carriers (n = 6) and non-carriers (n = 4) of a genetic variant of adenylyl cyclase 6 (AC S674). Rhythmic handgrip contractions (1 minute bout; 2 second contraction-relaxation period) were performed at three different intensities (20, 40, and 60% of maximal voluntary contraction force) to test the vasodilatory response to exercise. Additionally, two 5 minute infusions of isoproterenol (0.01 and 0.02 µg·kg-1·min-1 diluted in 5% dextrose) and one 10 minute infusion of propranolol (0.1 mg·kg-1 diluted in 0.9% saline) were …


The Effect Of Exercise On Cravings And Ad Libitum Smoking Following Concurrent Stressors, Angela J. Fong Aug 2013

The Effect Of Exercise On Cravings And Ad Libitum Smoking Following Concurrent Stressors, Angela J. Fong

Electronic Thesis and Dissertation Repository

Quitting smoking itself is a stressor; it is likely that other stressors occur concurrently and deplete self-regulatory resources. Failure to cope leads to smoking relapse. Exercise has been shown to attenuate cravings and withdrawal symptoms in previous research and has yet to be examined following concurrent stressors. This study examined the effect of an acute bout of moderate intensity exercise on psychological withdrawal symptoms (PWS), cravings and ad lib smoking after concurrent stressors (i.e., temporary abstinence and depletion). Twenty-five smokers were randomized into exercise or passive conditions. Results showed PWS were significantly exacerbated after temporary abstinence and again after depletion …


The Philosophy Of ‘Playing’ Games: A Lusory Introspection Of The Sincere Player And The Meaning Of Play Amidst The Moral Morass Of Contemporary Sport, Justin M. Rhoden Aug 2013

The Philosophy Of ‘Playing’ Games: A Lusory Introspection Of The Sincere Player And The Meaning Of Play Amidst The Moral Morass Of Contemporary Sport, Justin M. Rhoden

Electronic Thesis and Dissertation Repository

Play is a fundamental experience embedded within human culture. We all play in some perceptible manner that provides our lives with meaning we don’t ordinarily feel from other pursuits that are means-ended. Sport philosophers have depended upon the seminal theories of Huizinga and Caillois to shape their constraints on the play world. Huizinga’s and Caillois’ definition both use formal analysis to protect the play sphere however, their theories fail in providing justifiable reason to protect the play sphere and the meaning it has. I propose that understanding play from the perspective of existentialism provides a better way to understand its …


Understanding The Volunteer Youth Coaching Environment: A Psychological Contract Perspective, Alanna Harman Aug 2013

Understanding The Volunteer Youth Coaching Environment: A Psychological Contract Perspective, Alanna Harman

Electronic Thesis and Dissertation Repository

The purpose of this dissertation was to explore the volunteer coaching environment using psychological contract theory. Psychological contract posits that volunteers and their organization have implicit and explicit expectations of each other, and the breach and fulfillment of these expectations impact volunteers’ attitude and intended behaviour.

Study 1 explored the content of volunteer coaches’ psychological contract, and influences to the development of it. Interviews with 22 coaches of team sports, representing different demographic factors were included. The results revealed that volunteer coaches possess both transactional and relational expectations. Variation was found by coaching tenure and level of play. Sources external …


Somatosensory Stimulation Modulates Heart Rate Variability Changes Induced By Isometric Handgrip Exercise, Jacquie Baker Jul 2013

Somatosensory Stimulation Modulates Heart Rate Variability Changes Induced By Isometric Handgrip Exercise, Jacquie Baker

Electronic Thesis and Dissertation Repository

Functional imaging reveals overlapping forebrain and basal ganglia regions associated with heart rate (HR) and heart rate variability (HRV) regulation. Somatosensory stimulation (STIM) and isometric handgrip (HG) were used to test the hypotheses that a) STIM would modulate HG-induced changes to HR and HRV, and b) HG+STIM would produce different cortical activation relative to HG alone (n=12). During STIM, high-frequency (HF)-HRV increased (p<0.05), whereas HR did not change. During HG, HF-HRV decreased (p<0.01) while HR increased (p<0.001). HG+STIM reversed the HG-induced change in HF-HRV (p<0.01). However, the HR response to HG remained unaffected. HG increased insular activation, while ventral medial prefrontal cortex (vMPFC) activity decreased. HG+STIM produced similar vMPFC deactivation. However, insular activation was no longer evident. These data indicate that somatosensory inputs through STIM can modulate HG-induced changes to HF-HRV. Different insular activations during HG versus HG+STIM suggest afferent signals to the insula may inhibit descending motor signals affecting HF-HRV.


Assessing Multi-Unit Muscle Sympathetic Nerve Activity Across Groups: A Multivariate Approach To A Multivariate Concept, Danielle N. Brewer Jun 2013

Assessing Multi-Unit Muscle Sympathetic Nerve Activity Across Groups: A Multivariate Approach To A Multivariate Concept, Danielle N. Brewer

Electronic Thesis and Dissertation Repository

Baseline muscle sympathetic nerve activity (MSNA) comparisons of age (young & old, n=40) and cardiovascular disease (CVD) state (young: Y, old: O, metabolic syndrome: MET, coronary artery disease: CAD, chronic heart failure: CHF, n= 36) groups were made to assess which MSNA variable(s) best describe group differences using a MANOVA-based approach across 10 variables. The hypothesis that action potential (AP) variables would better discriminate between groups than integrated variables was not supported. Burst frequency and incidence together significantly differentiated between groups with variability attributed to spikes/min and spikes/100hb removed. Significant group differences were noted for these variables such that Y


Associations Between Heart Rate Variability And Metabolic Syndrome Risk Factors, Melanie I. Stuckey May 2013

Associations Between Heart Rate Variability And Metabolic Syndrome Risk Factors, Melanie I. Stuckey

Electronic Thesis and Dissertation Repository

Metabolic syndrome (MetS) is a clustering of risk factors for cardiovascular disease (CVD) and type 2 diabetes (T2D) – two major causes of morbidity and mortality worldwide. Heart rate variability (HRV) is a non-invasive measure of cardiac autonomic regulation that predicts mortality and morbidity. Additionally, HRV is reduced in CVD, T2D and MetS. As such, HRV has potential to be a novel cardiometabolic risk factor to be included in clinical risk assessment. Therefore, the purpose of this thesis was to examine the relationships between MetS and HRV. A systematic review of cross-sectional studies examining relationships between HRV and MetS was …


The Error Protection Impact Of Inhibitory After-Effects In Location-Based Tasks And Their Preservation With Practice, Alexandra Lynn Stoddart Apr 2013

The Error Protection Impact Of Inhibitory After-Effects In Location-Based Tasks And Their Preservation With Practice, Alexandra Lynn Stoddart

Electronic Thesis and Dissertation Repository

In location-based tasks, responses related to (prime trial) distractor-occupied locations automatically undergo activation, followed by inhibition, which causes these responses to become execution resistant. Distractor-response execution resistance takes time to override, causing detrimental inhibitory after-effects in the form of delayed target reactions that later require this response (e.g., the spatial negative priming phenomenon). We learned here that these puzzling detrimental inhibitory after-effects can also have a ‘beneficial’ influence, whereby the repelling impact of execution resistance reduced the likelihood of its response being used erroneously on the probe trial (i.e., execution resistance provides error protection). Ideally, execution resistance-induced error protection effectiveness, …


Awareness Of Physical Activity Levels And Sedentary Behaviour: An Assessment Of Awareness Of Physical Activity Levels And Sedentary Behaviour Among Parents And Children, Tripat Simran Kaur Grewal Mar 2013

Awareness Of Physical Activity Levels And Sedentary Behaviour: An Assessment Of Awareness Of Physical Activity Levels And Sedentary Behaviour Among Parents And Children, Tripat Simran Kaur Grewal

Electronic Thesis and Dissertation Repository

The purpose of this study was to assess awareness of physical activity and sedentary behaviour among parents and children aged 10-13 years. Associations between awareness and factors including age, BMI, gender, and obesity status were also examined. A total of 53 parent-child dyads participated in the study. Agreement between parent and child subjective measures (self-report) and objectively measured physical activity was examined to determine awareness. Most parents (87%) and children (83%) overestimated child moderate-vigorous physical activity (MVPA) beyond 30 minutes/day. The majority of parents (87%) and children (85%) also underestimated child sedentary behaviour by at least 3 hours/day. Older children …