Physiology Commons^™

The Effect Of Temperature Extremes On Cardiorespiratory Function In The Grass Shrimp Palaemonetes Pugio: Oxygen Limited Thermal Tolerance, Teresa Mika

UNLV Theses, Dissertations, Professional Papers, and Capstones

Aquatic poikilothermic animals must either cope with or compensate for the mismatch in oxygen supply and demand present at high temperatures. Oxygen limited thermal tolerance explains how aerobic scope is limited by insufficient oxygen supply and sets the performance window in animals. This work explores the effects of temperature on the different components of the oxygen delivery system, in both normoxic and hyperoxic conditions to determine if supplying more oxygen to the system mitigates the effects of temperature effects on the cardiorespiratory system and extends oxygen limited thermal tolerance to higher temperatures. The effect of temperature and oxygen condition was …

Effect Of Racing Flats On Running Economy In Male Adolescent Runners, Paul Hafen

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to investigate whether running economy differs in racing flats versus standard running shoes in high school cross-country runners. In order to measure running economy the oxygen cost of running (mL O₂∙kg^-1∙min^-1) was measured in 20 male adolescent runners (mean age = 16.25 ± 0.97 years, 5 km best time = 17.52 ± 0.78 min) when running two separate trials at a controlled speed. The speed was determined by estimating treadmill running speed at 85% of each runner's VO_2max. Each trial required the participants to run while …

Oxidative Stress For An Acute Bout Of Bikram Yoga In Healthy, Trained Adults, Kimberly Anne Trocio

UNLV Theses, Dissertations, Professional Papers, and Capstones

BACKGROUND:Generation of free radicals resulting in oxidative damage has been linked to cellular damage, aging, and human disease. Many studies have reported that physical exercise can contribute to oxidative stress. Further, exercise in a hyperthermic environment can promote additional oxidative stress. It is important to consider that practices in yoga may be beneficial in reducing oxidative stress according to some studies. The compound effects of exercise and hyperthermic exposure are experienced in the practice of Bikram yoga, the original "hot" yoga. Because Bikram yoga and other hot exercise classes are an increasingly growing fitness trend, it is necessary to investigate …

The Effects Of Starvation Selection On Drosophila Melanogaster Life History And Development, Lauren A. Reynolds

UNLV Theses, Dissertations, Professional Papers, and Capstones

In nature, animals may endure periods of famine to complete their life cycles. Starvation stress will increase in populations as climates around the world change. To predict how populations may respond to such a stress, laboratory experimentation becomes essential. The evolutionary process of adaptation, its innovations and their trade-offs, can be studied in populations experiencing starvation stress. For this purpose outbred populations ofDrosophila melanogasterwere selected for starvation resistance in the laboratory.

After 60+ generations of starvation selection the starvation-selected flies have gone from surviving 2-3 days without food to 12-14 days without food. How this amazing feat of resistance is …

Exercise-Induced Neuroprotection In A Hemiparkinsonian 6-Hydroxydopamine Rat Model, Merrill Russen Landers

UNLV Theses, Dissertations, Professional Papers, and Capstones

Outside of finding a cure, one of the preeminent goals of research in Parkinson's disease (PD) is finding a neuroprotective treatment that when applied prior to the onset of the disease will decrease the risk and severity of the subsequent disease. One such treatment that has potential as a neuroprotective agent in PD is exercise. Several studies have found forced exercise to be protective of Parkinson's disease in adult rodent models; however, few of these studies have used a design wherein voluntary exercise was evaluated. Moreover, no study has used a true neuroprotective design in which exercise was applied prior …

Embryonic Development Of The Grass Shrimp, Palaemonetes Pugio, And The Influence Of Salinity On Cardiac Physiology, Amie Lynn Romney

UNLV Theses, Dissertations, Professional Papers, and Capstones

The grass shrimp, Palaemonetes pugio, inhabit the brackish waters along the Atlantic coast of North America and are a key component of the estuarine ecosystem. These decapod shrimp can tolerate large fluctuations in environmental parameters including daily and seasonal fluctuations in salinity between 0 to 55 parts per thousand (seawater at 30-32 ppt). Any observed distribution patterns of adult P. pugio in relation to salinity may be accounted for by their relative ability to tolerate a range in salinity and their ability to maintain internal water volumes and cardiac performance in the earliest life stage, the embryonic period. This thesis …

Physiological Implications Of Natural Versus Induced Arousal From Torpor, Jenifer C. Utz

UNLV Theses, Dissertations, Professional Papers, and Capstones

During the hibernation season, animals oscillate between periods of torpor and periods of interbout arousal (IBA). During torpor, body temperature is often near 0° C and metabolism is severely depressed. Oxygen consumption, a proxy for aerobic metabolism, may fall to 1% of active values. Many physiological processes including cardiovascular, respiratory, and cellular functions nearly cease. During the IBA, euthermic body temperature is restored and most systemic and cellular processes function at fully active levels. The transition period between these two physiologically dissimilar states is called arousal.

The rate of rewarming (RRW) during arousal was previously expected to progressively increase until …

The Role Of Larval Fat Cells In Starvation Resistance And Reproduction In Adult Drosophila Melanogaster, Jerell Roland Aguila

UNLV Theses, Dissertations, Professional Papers, and Capstones

The intricate life cycle of holometabolous insects includes well-defined larval and adult stages associated with feeding and non-feeding periods. The larval stage is distinguished by prevalent feeding and is necessary for supporting the animal as it quickly grows. The larval stage also serves as the period for the animal to obtain adequate energy stores, primarily in the larval fat body, to fuel the animal through the non-feeding pupal and immature adult stages. Acquiring sufficient energy stores is paramount for the success of the adult animal. In fact, certain insects, such as silkworms and mayflies, do not feed as adults and …

An Examination Of Body Composition Measurement Methods In Children, Robert Kaplan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction . Body-composition methods include underwater weighing (UWW), skinfold thickness (SKF), bioelectrical impedance (BIA), and the BOD POD. Although these techniques are used routinely, each has its inherent limitations, especially in children. Purpose . The purpose of this study was to examine the various methods of body composition in children. Methods . The body composition of 7 boys between the ages of 12-14 (13.1 +/- 1.1 years) was determined using the BOD POD, UWW, SKF, and BIA. Results . Percent body fat estimated from the BOD POD (21.9 +/- 7.8%BF) was not significantly different than the estimated percent fat from …

Integrated Responses Of Crustaceans Inhabiting Estuaries To The Challenges Of Feeding And Digestion In Low Salinity, Daniel Luke Curtis

UNLV Theses, Dissertations, Professional Papers, and Capstones

Estuaries are highly productive and serve as vital habitats for numerous decapod crustacean species. However, the environmental conditions within estuaries are often highly dynamic and subject to large changes in salinity and temperature that occur on seasonal and tidal scales. Not all of the species occupying these habitats are adept in coping with changes in these environmental conditions. This dissertation describes the influence of low salinity conditions on the 1) habitat preference, 2) feeding behaviour and 3) digestive physiology of crustaceans inhabiting estuaries. I have primarily focussed on a weak osmoregulator, the Dungeness crab, Cancer magister , but have also …