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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Investigation of C-Reactive Protein and Leptin as Biomarkers of Obesity with Potential Clinical Utility

Friedman, Rachel Ann 01 August 2011 (has links)
Obesity and its subsequent disease states are major health problems in the United States. In many ways, obesity can be considered a “disease state” itself due to the changes it causes on the body. High-intensity exercise also places acute stress the body, putting humans in recovery from exercise in a state that may be analogous to a temporary disease state. The purpose of this study was to examine biomarkers associated with obesity (CRP and Leptin) before and after continuous and intermittent bouts of exercise in an obese but otherwise healthy sample vs. a healthy, non-obese sample. This investigation focused on examining the obese sample’s biomarkers at rest compared to those of the healthy group immediately and 1 hour-post exercise. Eighteen male subjects participated, with nine in each group. Each subject performed a VO2 max test and a series of three anaerobic Wingate tests at least one week apart in a cross-over study design. Blood was taken at baseline, immediately-post, and 1-hour post for each exercise mode. A significant difference was noted between groups for CRP at baseline on the VO2 testing day. A significant difference between groups existed in leptin levels at baseline on both testing days. The only significant change was the decrease in leptin from post to 1- hour post for during the VO2 in the obese group. However, both exercise protocols demonstrated various effects on the subjects and groups. Healthy participants were examined individually, and two of them showed possible signs of being at risk for obesity and its subsequent disease states based on post exercise “spikes” in CRP and leptin that caused the levels of the biomarkers to be closer to those in the obese group at rest. Another three subjects saw at least two spikes. Thus, a total of five subjects could potentially be “at-risk” based on the assumptions of the present study. These results suggest CRP and Leptin could potentially hold the ability to classify someone in a “preobesity state.” Further investigations are warranted based on these initial results and should focus on biomarkers more specific to obesity.
32

none

Chen, Chao-Ling 08 August 2001 (has links)
Abstract The combinations of four temperatures (20, 25, 30, 35¢J) and six salinities (5, 10, 15, 20 ,25, 30psu ) were employed to study the effects of environmental factors on the speed of ciliary movement of the gill and the oxygen consumption of hard clam Meretrix lusoria and purple clam Sanguinolaria rostrata. The results show that, at the same salinities, the speed of ciliary movement of the gill and the oxygen consumption of M. lusoria increased with increasing temperature and reached the maximum at 30¢J, but declined at 35¢J. In contrast , the speed of ciliary movement of the gill and the oxygen consumption of S. rostrata increased with increasing temperature, and the maximum was at 35¢J. S. rostrata can adapt to higher temperature than M. lusoria does. At the same temperature, the speed of ciliary movement of the gill and the oxygen consumption of two bivalves increased with increasing salinity, reaching its maximum at 15~25psu, and declining at higher salinity ranges. These two bivalves like to live in estuaries. The maximal speed of ciliary movement of the gill and the maximal oxygen consumption of M. lusoria occurred at 30¢J, 20 psu (1.23 cm/min and 1.78 mgO2/hr/g, respectively). The ratio of the maximun to the minimun were 2.5 and 2.8, respectively. The maximal speed of ciliary movement of the gill and the maximal oxygen consumption of S. rostrata were at 35¢J, 25 psu (1.64 cm/min and 1.45 mgO2/hr/g, respectively). The ratio of the maximun to the minimun were 4.0 and 5.8, respectively. Temperature and salinity had more remarkable effects on S. rostrata than on M. lusoria. In another experiment, the combinations of four temperatures (20 ,25 ,30 ,35¢J) and three salinities (10, 20, 30 psu) were employed to study the effects on the speed of ciliary movement of the gill and the oxygen consumption of small M. lusoria and small S. rostrata. The results show that the effects of all temperature-salinity combination on the speed of ciliary movement of the gill and the oxygen consumption of the small bivalves were similar to that of the large ones. The physiological conditions of the small bivalves were similar to that of the large ones. The maximal speed of ciliary movement of the gill and the maximal oxygen consumption of small M. lusoria were at 30¢J, 20 psu (1.31 cm/min and 5.56 mgO2/hr/g, respectively). The ratio of the maximun to the minimun were 2.5 and 3.0, respectively. The maximal speed of ciliary movement of the gill and the maximal oxygen consumption of small S. rostrata were at 35¢J, 20 psu (1.67 cm/min and 3.96 mgO2/hr/g, respectively). The ratio of the maximun to the minimun were 2.9 and 7.1, respectively. Temperature and salinity had more remarkable effects on small S. rostrata than small M. lusoria. Our results also show that the oxygen consumption is positively correlated with the speed of ciliary movement of the gill in both bivalves (R2¡á0.94). The speed of ciliary movement of the gill can be regarded as an physiological indicator. The speed of ciliary movement of the gill of M. lusoria changed very significantly when the temperature was suddenly changed 5¢J or when the salinity was suddenly changed 10psu. The condition then stabilized only gradually. The speed of ciliary movement of the gill showed no pronounced variations after 50~70 minutes. We found that when the temperature or salinity was changed suddenly, the physiological condition of M. lusoria was disturbed and became stable after 70 minutes. M. lusoria died at 5psu (35¢J), but S. rostrata didn¡¦t. S. rostrata can adapt to higher temperature and lower salinity. The cultivation of S. rostrata is easier than M. lusoria. The effects of temperature changes were more significant than those of salinity. Temperature variations were more important than salinity variations on cultivation of M. lusoria and S. rostrata.
33

Macrobenthic community structure and total sediment respiration at cold hydrocarbon seeps in the northern Gulf of Mexico

Nunnally, Clifton Charles 15 November 2004 (has links)
Cold seeps are areas of high biomass in the deep-sea, the impacts of these food-rich environments upon the sediment community is unknown in the Gulf of Mexico. The structure and function of benthic communities was investigated at food-rich and food-limited sites on the northern Gulf of Mexico continental slope. Cold seeps were richer in macrofauna densities and total sediment respiration, but were poorer in biomass and taxa diversity than normal slope communities. Decreased diversity is seen at most chemosynthetic communities and suggests a competition for resources. The spatial extent of these results at seeps is unknown and may be a localized, bioenhancement effect caused by seeping fluids.
34

EFFECTS OF AMMONIA ON GROWTH AND METABOLISM IN TILAPIA, OREOCHROMIS NILOTICUS

Morrow, RICHARD 11 August 2009 (has links)
Nile tilapia (Oreochromis niloticus) is an important species in the expansion of aquaculture, which supplements strained natural fish stocks worldwide. Although nitrogen accumulation in aquaculture has been documented as hazardous, recent studies have highlighted its potential to positively affect fish growth. The current study investigates the growth and oxygen consumption of juvenile Nile tilapia exposed to high (sub-lethal) and low levels of total water ammonia (TAmm). The first series of experiments aimed to determine the effects of high TAmm toxicity on indicators of metabolic rate and whole-body growth. Results of non-acclimation exposures to ammonia suggest that high levels of TAmm (1000, 2000 and 4000 μM) negatively affect oxygen consumption and ventilation rates, with reduced respiratory efficiency at 4000 μM. This effect on oxygen consumption was not present after a 48hr acclimation period to TAmm concentrations. Tilapia grown under the TAmm treatment conditions had significantly reduced weight and length after 84 days at concentrations of 2000 and 4000 μM. The second series of experiments investigated metabolic rate and growth under conditions of low-level TAmm (75, 150, 300, 600, 1200 and 2400 μM) to determine potential positive effects on growth. The results of these experiments indicated that oxygen consumption was reduced in non-acclimated fish at concentrations of 75, 150 and 300 μM, which were therefore examined in subsequent growth experiments. This oxygen consumption reduction was not present after 48hrs of ammonia acclimation. Tilapia grown at low TAmm (≤300 μM) did not exhibit significant differences in weight, length, condition factor or specific growth rate within the 56-day experiment. This study demonstrates that high levels of TAmm significantly impair tilapia whole-body growth. Furthermore, low levels of TAmm (≤300 μM) do not appear to affect growth. In both series, an initial reduction in metabolic rate was noted in non-acclimated fish, but was not present after 48hr TAmm acclimation. While fish “recovered” from initial effects of high TAmm on oxygen consumption and ventilation, significant negative effects on growth were noted. This study suggests that tilapia adapt to the initial effects of TAmm through a process that, at high levels, is energetically costly and compromises growth. / Thesis (Master, Biology) -- Queen's University, 2009-08-04 11:33:48.94
35

The Metabolic Demand of a Vinyasa Yoga Session

2014 December 1900 (has links)
Vinyasa yoga, also known as power flow yoga, is growing in popularity in western cultures. Vinyasa yoga is characterized by moving with the breath and connecting the postures by a series of dynamic movement in between traditional yoga poses. The purpose of this thesis was to determine the intensity and metabolic costs of a typical Vinyasa yoga routine by measuring respiratory gas exchange, heart rate, and perceived rating of exertion. Secondary purposes were to determine whether there were differences between beginner and advanced practitioners and between males and females. Eight beginner (4 males and 4 females) and eight advanced (4 males and 4 females) yoga practitioners were tested while completing a Vinyasa yoga routine. Participants first completed a maximal aerobic test on a treadmill to determine maximal aerobic capacity, and to allow the assessment of relative workload during a subsequent yoga session. After adequate rest, the participant completed a 90-minute familiarization of the Vinyasa yoga session at his or her own skill level. After 4 – 7 days the participants returned, where the beginners completed the beginner routine and the advanced practitioners were randomly assigned to do either the beginner or advanced routine. The advanced practitioners came back on a separate day to complete the routine they had not yet completed. To allow participants to move freely, a portable system (Cosmed K4b2) was used to measure respiratory gas exchange (i.e. oxygen consumption and carbon dioxide output). A heart rate monitor was worn to collect heart rate data. Rating of perceived exertion was measured at set times throughout the session. The mean metabolic equivalents (METs) of Vinyasa yoga (4.7) were significantly higher (p < 0.001) than the 3.0 METs needed to achieve a moderate intensity based on the Canadian Physical Activity Guidelines. During the yoga session, 68 ± 10 minutes were spent above 3.0 METs (moderate intensity) and of those minutes, 16 ± 16 were spent above 6.0 METs (vigorous intensity). Based on the Canadian Guidelines for Physical Activity of 150 minutes per week of moderate intensity activity, three 90-minute Vinyasa yoga sessions a week can meet the recommendations for adults.
36

Field based testing protocols to monitor training adaptations and performance in elite rowers.

Vogler, Andrew James, avogler@virginbroadband.com.au January 2010 (has links)
Laboratory-based rowing tests are the established standard for assessing fitness traits among elite rowers, and for prescribing individualised exercise intensities for training. But because tests occur on a rowing ergometer, the specificity of laboratory testing has been questioned compared with the criterion of on-water rowing. This project validated equipment required to replicate a laboratory-based rowing test in the field and evaluated the feasibility of on-water tests. Ergometer and on-water test results were compared to assess the validity of ergometer-derived training prescriptions and to establish the effectiveness of on-water tests for monitoring longitudinal fitness changes and for predicting rowing performance. Concept2 rowing ergometers (Morrisville, USA) have frequently been used for rowing tests. Although subtle design variations exist between the different models of Concept2 ergometer, there were no substantial differences between the results from incremental rowing tests using Model C and Model D ergometers. The Concept2 Model D was therefore accepted as the standard ergometer for subsequent laboratory tests. Typical error (TE) results from duplicate Concept2 Model D tests conducted 2-4 d apart showed that laboratory tests were highly reliable (TE: maximal power = 2.8%, peak oxygen consumption = 2.5%). As oxygen consumption (VO2) is measured routinely during laboratory rowing tests, it is necessary to obtain similar measurements during any on-water protocol. The MetaMax 3B portable indirect calorimetry system (Cortex, Leipzig, Germany) was therefore validated against a first-principles, laboratory-based indirect calorimetry system (MOUSe, Australian Institute of Sport, Canberra, Australia). VO2 from the MetaMax was significantly higher during submaximal exercise (p=0.03), although results were within 0.16 L.min-1 (4.1%) across all exercise intensities. There was good agreement between duplicate MetaMax trials separated by ~2 d; mean VO2 was within 0.11 L.min-1 (2.5%) and TE was ¡Ü2.3%. The specificity of rowing testing was improved using an On-water incremental test that replicated a laboratory-based Ergometer protocol. However, the individual variation in physiological responses between-tests meant that training intensity recommendations from the Ergometer test were not always applicable to on-water training. Furthermore, measurements from the On-water protocol displayed similar or lesser reliability (TE=1.9-19.2%) compared with the Ergometer test (TE=0.1-11.0%). As an effective fitness test must also be sensitive to longitudinal changes, the responses to 6 wks training were compared between the Ergometer and On-water methods. The magnitude of On-water training effects were usually greater (small Cohen¡¯s effect size) compared with the Ergometer test (trivial effect), although On-water and Ergometer tests both indicated that training responses were negligible because virtually all changes were less than one of their respective TEs. Correlations between test results and rowing performance were largest when rowing mode was matched between conditions, but Ergometer results provided the highest correlations (Ergometer vs. 2000-m ergometer time-trial: R= -0.92 to -0.97 compared with On-water vs. On-water maximal power output: R=0.52 to 0.92). Although On-water tests improved the specificity of on-water training prescriptions, these tests provided no obvious benefits for monitoring longitudinal fitness changes or performance compared with Ergometer tests. Given that On-water tests are also more time consuming and logistically challenging, their practical application is limited.
37

Severe hypoxemia during apnea in humans : influence of cardiovascular responses /

Lindholm, Peter, January 2002 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / Härtill 4 uppsatser.
38

Graded exercise stress testing treadmill protocols comparison of peak exercise times in cardiac patients /

Salameh, Ahlam. January 2009 (has links)
Thesis (M.S.)--University of Akron, Dept. of Sport Science and Wellness Education-Physical Education, 2009. / "August, 2009." Title from electronic thesis title page (viewed 10/7/2009) Advisor, Ronald Otterstetter; Committee members, James Rosneck, Laura Richardson; Department Chair, Victor Pinheiro; Dean of the College, Mark D. Shermis; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.
39

Oxygen tension in the fetus continuous measurement of fetal subcutaneous Po2 with a needle-electrode : an experimental and clinical investigation /

Aarnoudse, Jan Gerard. January 1980 (has links)
Thesis (doctoral)--Rijksuniversiteit te Groningen.
40

The influence of aerobic exercise on double product break point in low to moderate risk adults

Campbell, Diane L. January 2009 (has links)
Thesis (M.S.)--Ball State University, 2009. / Title from PDF t.p. (viewed on Apr. 16, 2010). Includes bibliographical references.

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