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Influence of parental swimming stamina on the cardiac and metabolic performance of larval zebrafish (Danio rerio).

Description: Superior swimming stamina in adult fish is presumably passed on to their offspring, but the ontogeny of the appearance of superior stamina and the requisite enhanced cardio-respiratory support for locomotion in larval fishes has not been determined. Is the expression of the suite of parental traits enabling superior swimming stamina in their offspring dependent upon their achieving juvenile/adult morphology, or does it appear earlier in their larvae? To answer this, adults were classified int… more
Date: May 2007
Creator: Gore, Matthew R.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Stability of Field Emitter Arrays to Oxygen Exposures

Description: The purpose of these experiments was to determine the degradation mechanisms of molybdenum based field emitter arrays to oxygen exposures and to improve the overall reliability. In addition, we also evaluated the emission current stability of gold-coated field emitter arrays to oxygen exposures. oxygen at 1x10-6 torr was introduced into the chamber through a leak valve for different lengths of time and duty cycles. To ensure identical oxygen exposure and experimental measurement conditions, ti… more
Date: December 2002
Creator: Godbole, Soumitra Kumar
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The Effect of Mode and Intensity on Vo2 Kinetics in the Severe Intensity Domain

Description: The purpose of this study was to evaluate the effect of mode and intensity on VO2 kinetics in the severe intensity domain. Seventeen participants completed 3-7 tests each on a cycle ergometer and treadmill. For each test, Tfatigue, VO2max, Tmean response, VO2GAIN, TVO2max and T@VO2max were determined. Linear regression techniques were used to describe the relationship between TVO2max and Tfatigue . VO2max values were higher in running. The VO2 response profile was faster for running than cycl… more
Date: May 2000
Creator: Updyke, Rhonda S.
Item Type: Refine your search to only Thesis or Dissertation
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Oxygen Uptake Kinetics in Severe Intensity Exercise

Description: The purpose of this study was to describe mathematically the oxygen uptake kinetics during cycle ergometry, and to examine the effect of intensity on the kinetic responses within the severe domain. Sixteen volunteers performed a series of exercise tests at a range of intensities selected to elicit fatigue in ~3 to 10 min. A simple mono-exponential model effectively described the response across all intensities. There was a positive correlation between the response time and the time to fatigue, … more
Date: May 2000
Creator: Blumoff, Sonja
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Immunohistochemistry of the Gills of the Channel Catfish Ictalurus Punctatus: Cells and Neurochemicals That May Be Involved in the Control of Cardioventilatory Reflexes

Description: In teleost fishes the neurochemicals involved in sensing and responding to hypoxia are unresolved. Serotonergic branchial neuroepithelial cells (NECs) are putative O2 chemoreceptors believed to be homologous to the neural crest (NC) derived APUD (amine-precursor uptake and decarboxylation) pulmonary NECs and carotid body type-1 glomus cells. Branchial NECs contain serotonin (5-HT), thought to be central to the induction of the hypoxic cardioventilatory reflexes. However, application of 5-HT … more
Date: December 2013
Creator: Oden, David S.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Relationship Between Ventilation and Oxygen Uptake at 40% And 85% of Peak Oxygen Uptake in 18-35-Year-Old Women Using the Arm Crank Ergometer

Description: This study investigated whether or not a relationship exists between ventilation and oxygen uptake at 40% and 85% of V02 peak intensity in 30 upper body fit and 30 unfit 18- 35-year-old women. The correlations between ventilation and oxygen uptake at 40% of peak intensity for the fit group (r = -.51) and the unfit group (r = -.48) were modestly negative. At 85% intensity the relationship between ventilation and oxygen uptake in the two groups was -.44 and -.66, respectively. The lower correlati… more
Date: May 1988
Creator: Zervopoulos, Peter C. (Peter Cosmas)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Predicting Peak Oxygen Uptake from Ratings of Perceived Exertion During Submaximal Cycle Ergometry

Description: The purpose of this study was to predict VO2pak using ratings of perceived exertion (RPE), heart rate (HR), and percent fat (PFAT). Subjects were males (n= 60) (PFAT, M SD = 14.4 6.1) and females (n= 67) (PFAT, M SD = 23.4 4.9) with ages ranging from 18 to 33 years. Subjects performed an incremental cycle ergometer protocol and RPE, HR and Vo2 were measured at each stage until VO2 ak was achieved. Mean RPE and HR at the submaximal workload of 100 watts were, (RPE100) M= 12.7 2.6 and (HR100) M= … more
Date: May 1992
Creator: Fairfield, Eric S. (Eric Scott)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Respiratory Responses in the Freshwater Snail (Pomacea Bridgesii) are Differently Affected by Temperature, Body Mass,and Oxygen Availability

Description: Pomacea bridgesii is a snail species native to tropical and sub-tropical regions, where it usually faces variability in water, temperature and oxygen level. This study of the effect of temperature on mass-specific oxygen consumption (ṀO2) and its relation to body weight shows that the ṀO2 of juvenile snails in normoxia (18-21 kPa) acclimated at temperature of 25°C ranged from 5 to 58 µMol O2/g/h, with a mean of 41.4 ± 18.3 µMol O2/g/h (n=7). Adult snails in normoxia at 25°C show less variat… more
Date: August 2016
Creator: Frifer, Wenasa Salem
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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The Effect of Running Speed on VO2 Kinetics in the Severe Exercise Domain

Description: There has been an interest in the kinetics of the V02 response during exercise at various intensities. However, most studies focus on the response of submaximal intensities whereas few studies have examined V02 kinetics at severe intensities. The purpose of this study was to evaluate the effect of exercise intensity on V02 kinetics over a range of severe intensities.
Date: December 1997
Creator: Williams, Christine Suzanne
Item Type: Refine your search to only Thesis or Dissertation
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Effect of Silyation on Organosilcate Glass Films

Description: Photoresist stripping with oxygen plasma ashing destroys the functional groups in organosilicate glass films and induce moisture uptake, causing low-k dielectric degradation. In this study, hexamethyldisilazane (HMDS), triethylchlorosilane and tripropylchlorosilane are used to repair the damage to organosilicate glass by the O2 plasma ashing process. The optimization of the surface functionalization of the organosilicate glass by the silanes and the thermal stability of the functionalized surfa… more
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Date: August 2004
Creator: Kadam, Poonam
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Heart rate and oxygen consumption during the critical prenatal period in chicken embryos (Gallus gallus): Influence of light cues and the onset of pulmonary ventilation.

Description: To examine if a rhythm can be entrained in either heart rate or oxygen consumption in late stage embryos (days 17-19.5) with light as a zeitgeber, chicken embryos were incubated in complete darkness (D:D) and 12:12 light:dark cycle (L:D). Light had no impact on oxygen consumption (390 µL O2∙min-1∙egg-1) but increased heart rate for non-internally pipped embryos (260 to 270 beats∙min-1 during light cycle). Oxygen consumption increased independent of pipping while heart rate increased (255 to 2… more
Date: December 2004
Creator: Brown, Jessie W.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Exercise Capacity Following Four Hours of Head-Down Rest in Endurance-Exercise-Trained and Untrained Subjects

Description: Peak oxygen uptake (VO2PEAK) in endurance exercise trained (ET =8) subjects (VO2PEAK = 61.7 1.6 ml 02.kg.min-1) was compared to the V02 PEAK of untrained (UT = 8) subjects (V02 PEAK = 38.4 1.7 ml 02 -kg.min1) after four hours of -6* head-down rest (HDR).Although both groups showed a reduction in blood volume (BV) following HDR, this decrement was greater for ET subjects (delta BV = -3.23 0.46 mi/kg; P <0.05). The ET subjects had a greater decrease in VO2=(delta 02E -5.58 1.05 ml 02-kg.min-1; P … more
Date: December 1990
Creator: Williamson, Jon W.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Use of repeated tests and rolling breath averages affects the precision of quantifying the VO2 response profile in moderate intensity cycling.

Description: The purpose of this study was to determine whether working in the field of deaf education, as opposed to general education, results in a higher level of technology integration. A secondary goal was to determine if deaf educators who are deaf integrate technology at a higher level than their hearing counterparts. The instrument chosen for this study was the LoTi Technology Use Profile, a tool used to explore the role of technology in the classroom. A total of 92 participates were included in t… more
Date: August 2006
Creator: Pedini, Daniela Marie
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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VO2 response profile in heavy intensity cycling after heavy intensity arm or leg exercise.

Description: The elevated CO2 levels, elevated temperature, and lower blood pH that may occur during exercise should enhance O2 delivery to the exercising muscles. It was hypothesized that performance of prior exercise (PE) would result in a faster VO2 response, as well as a reduced slow component contribution, in subsequent exercise bouts. Five women (21 ± 1 yr) and 10 men (23 ± 2 yr) performed nine 6-min bouts of heavy intensity cycle ergometer exercise (i.e., above the ventilatory threshold, individual… more
Date: December 2006
Creator: Ptak, April Louise
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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The role of prostaglandins, nitric oxide and oxygen in the ductus arteriosi of the pre-term chicken embryo (Gallus domesticus).

Description: The chicken ductus arteriosi (DA) are two embryonic blood vessels that shunt blood away from the non-ventilated lungs and towards the body and chorioallantoic membrane. I show that prostaglandins have a diminished role in maintaining chicken DA patency and nitric oxide inhibits oxygen induced contraction of the day 19 proximal DA in a time dependent manner. The pathways governing oxygen induced contraction in the chicken DA are similar to those found in mammals and include contributions from RO… more
Date: December 2007
Creator: Greyner, Henry José
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Kinetic Study of the Reactions of Oxygen Atoms with Nitric Oxide and Silane

Description: The rate constant for the reactions of oxygen atoms with nitric oxide and silane were determined using a discharge flow apparatus. A microwave discharge through O2N2 and Ar was used to produce oxygen atoms. The rate constant for the reaction O + NO + Ar was determined to be (7.0+0.4) x 10^32 cm^6 s^-1 and is in good agreement with previous measurements. Modeling of the O +SiH₄ reaction was performed to determine the correction to the rate constant due to secondary reactions. The rate constant f… more
Date: August 1992
Creator: Taylor, Craig A. (Craig Allan)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Study of Silver Deposition on Silicon (100) by IR Spectroscopy and Patina Formation Study of Oxygen Reduction Reaction on Ruthenium or Platinum

Description: To investigate conditions of silver electroless deposition on silicon (100), optical microscope, atomic force microscope (AFM) and attenuated total reflection infrared spectroscopy (ATR-FTIR) spectroscopy were used. Twenty second dipping in 0.8mM AgNO3/4.9% solution coats a silicon (100) wafer with a thin film of silver nanoparticles very well. According to AFM results, the diameter of silver particles is from 50 to 100nm. After deposition, arithmetic average of absolute values roughness (Ra) i… more
Date: August 2009
Creator: Yang, Fan
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Partner: UNT Libraries
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Effects of X-Irradiation of Respiration in Frog Brain Tissue Slices Using the Oxygen Electrode Method

Description: The effects of X-irradiation at dosages of 40 r, 80 r, 160 r, 240 r, 320 r, 400 r, 800 r, 4 Kr, 8 Kr, and 16 Kr on the oxygen uptake of frog brain (Rana pipiens) tissue slices were studied. A membrane-covered oxygen electrode method was used to measure the respiratory rate. Continuous recordings were made before, during, and following X-irradiation in all of the test experiments. X-irradiation was delivered from a G. E. beryllium window X-ray unit at 120 KVP, 5 ma with a 1/4 mm Al filter.
Date: August 1971
Creator: Lin, Chen-hsiung
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Development of Indium Oxide Nanowires as Efficient Gas Sensors

Description: Crystalline indium oxide nanowires were synthesized following optimization of growth parameters. Oxygen vacancies were found to impact the optical and electronic properties of the as-grown nanowires. Photoluminescence measurements showed a strong U.V emission peak at 3.18 eV and defect peaks in the visible region at 2.85 eV, 2.66 eV and 2.5 eV. The defect peaks are attributed to neutral and charged states of oxygen vacancies. Post-growth annealing in oxygen environment and passivation with sulp… more
Date: December 2011
Creator: Gali, Pradeep
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Chronic Hypoxia and Hyperoxia Modifies Morphology and Vegf Expression of the Lungs of the Developing Chicken (Gallus Gallus Domesticus)

Description: This study determines effects of oxygen levels on morphology and VEGF expression of developing chicken lungs following incubation in normoxia (21% O2), hypoxia (15% O2) or hyperoxia (30% O2), until developmental days 16 or 18. Lung morphology was assessed using light microscopy, while VEGF expression was determined with ELISA. In hypoxia, the proportion of parabronchial tissue and parabronchi including lumina increased from day 16 to 18 (61 to 68% and 74.2 to 82.2%, respectively). Non-parabronc… more
Date: December 2012
Creator: Lewallen, Melissa Anjanette
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Studies Concerning the Production of Lactobacillic Acid in Lactobacillus Plantarum

Description: This study is concerned with certain factors affecting the content of lactobacillic acid in Lactobacillus plantarum. Three main areas of investigation are reported herein. The effects of both the oxygen tension and the pH of the culture medium on the accumulation of lactobacillic acid were determined. In addition, monolayer studies were conducted to determine the influence of cyclopropane fatty acid content on the molecular packing of membrane lipids.
Date: May 1973
Creator: Halper, Laura Ann
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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