UNT Theses and Dissertations - 3 Matching Results

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Evaluating the Pulse Sensor as a Low-Cost and Portable Measurement of Blood Pulse Waveform

Description: This study was aimed at determining whether the digital volume pulse waveform using the Pulse Sensor can be used to extract features related to arterial compliance. The Pulse Sensor, a low-cost photoplethysmograph, measures green light reflection in the finger and generates output, which is indicative of blood flow and can be read by the low-cost Arduino UNO™. The Pulse Sensor code was modified to increase the sampling frequency and to capture the data in a file, which is subsequently used for waveform analysis using programs written in the R system. Waveforms were obtained using the Pulse Sensor during two 30-s periods of seated rest, in each of 44 participants, who were between the ages of 20 and 80 years. For each cardiac cycle, the first four derivatives of the waveform were calculated and low-pass filtered by convolution before every differentiation step. The program was written to extract 19 features from the pulse waveform and its derivatives. These features were selected from those that have been reported to relate to the physiopathology of hemodynamics. Results indicate that subtle features of the pulse waveform can be calculated from the fourth derivative. Feature misidentification occurred in cases of saturation or low voltage and resulted in outliers; therefore, trimmed means of the features were calculated by automatically discarding the outliers. There was a high efficiency of extraction for most features. Significant relationships were found between several of the features and age, and systolic, diastolic, and mean arterial blood pressure, suggesting that these features might be employed to predict arterial compliance. Further improvements in experimental design could lead to a more detailed evaluation of the Pulse Sensor with respect to its capability to predict factors related to arterial compliance.
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Date: May 2016
Creator: Smithers, Breana Gray
Partner: UNT Libraries

Coaching Efficacy Beliefs and Transformational Leadership Behaviors: Their Ability to Predict Motivational Climate

Description: This study investigated the relationship between belief in coaching abilities (coaching efficacy beliefs, CEB), transformational leadership behaviors (TLB), and motivational climate development of current strength and conditioning coaches working with high school level athletes. The measures used were the coaching efficacy scale for high school teams (CES II-HST, Myers et al.,2000), the differentiated transformational leadership inventory (DTLI, Callow et al., 2009), and the patterns of adaptive learning scales (PALS, Midgley et al., 2000). It was hypothesized that CEB and TLB would influence motivational climate development, while coaches' background characteristics would correlate with CEB, TLB, and motivational climate development. The 60 coaches who participated reported an average of thirteen (SD=8) years of experience and 51 were Certified Strength and Conditioning Specialists. Coaches reported high efficacy, frequent use of TLB, and development of a moderately high task- and somewhat ego-involving motivational climate. Correlations between demographic variables and CEB, TLB, and motivational climate development revealed three significant relationships: years of experience with CEB, and professional development activities and athlete to coach ratio with ego-involving climate development. CEB and TLB had a strong positive correlation. Two regression analyses were conducted to determine if the outcomes of the CEB and TLB measures predicted motivational climate development. The only significant predictor was TLB positively predicting development of a task-involving motivational climate. Strength coaches can utilize the findings of this study help shape their leadership behaviors and develop a task-involving motivational climate that emphasizes effort, improvement, and cooperative learning and is optimal for athlete development and performance.
Date: August 2016
Creator: Runge, Michael J
Partner: UNT Libraries

Does Downhill Running Alter Monocyte Susceptibility to Apoptosis?

Description: Introduction/purpose: Recovery from muscle damage involves a type of programmed cell death known as apoptosis. Damage Associated Molecular Patterns (DAMPs) are released after muscle damage and may cause premature apoptosis in monocytes infiltrating the damaged site. This may alter the time course of events towards recovery. Therefore, the purpose of this study was to investigate if downhill running causes a change in the susceptibility of monocytes to apoptosis. Methods: Participants (5 male, 6 female) completed a downhill running protocol consisting of 6-5 minute bouts at a speed of 6-9mph on a -15% grade treadmill. Venous blood samples were collected immediately pre-exercise (PRE), in addition to 4 -h, 24 -h and 48 -h post-exercise. Creatine kinase (CK) was measured to give an indication of muscle damage. Monocytes were analyzed by flow cytometry for expression of multicaspase and annexin v reagent was used to detect changes in the plasma membrane. A MILLIPLEX MAP human early apoptosis magnetic bead 7-plex kit (EMD Millipore, Billerica, MA) was used to assess the relative concentration of phosphorylated protein kinase B (Akt), Bcl-2 associated death promoter (BAD), B cell lymphoma-2 (Bcl-2), active caspase-8, active caspase-9, c jun N terminal kinase (JNK) and tumor protein p53 by Luminex multiplex assay. Results: CK peaked at 24- h. Monocytes showed greater expression of multicaspase at 24 –h and 48 -h than at PRE. Bcl-2, p53 and caspase-8 were all significantly greater at 24 –h than at PRE. Conclusion: Downhill running did alter the apoptotic response of monocytes and therefore may be important in the recovery process from muscle damage.
Date: August 2016
Creator: Pennel, Kathryn Ann Foster
Partner: UNT Libraries