Life Sciences Commons^™

Using Noninvasive Calibrated Cuff Plethysmography To Observe The Effects Of Cold-Water Immersion On Arterial Compliance, Rita M. Grigorian

Master's Theses

As the prevalence of cardiovascular diseases continues to exponentially grow in populations across the globe, the necessity of determining underlying factors, effective methods of diagnoses, and universally available preventive measures also grows. Early detection of endothelial dysfunction, a proven precursor of cardiovascular diseases, can be extremely impactful in encouraging preventative measures and early intervention before medical conditions become chronic. In recent years, ice plunging, a form of cryotherapy involving full body immersion in cold water, has gained popularity within circles of fitness and health practitioners, gaining the interest of people of all backgrounds. Certain parallels observed between the human physiological …

Effects Of Intertidal Position On The Response To Oxygen And Desiccation Stress In The Common Acorn Barnacle, Balanus Glandula, Megan M. Dotterweich

Master's Theses

Sessile invertebrates in the rocky intertidal experience intermittent periods of air exposure due to tidal flux, presenting risks of temperature extremes, hypoxia, nutrient limitation, and most dangerously, desiccation. Microscale variation in severity and frequency of these risks is widely dependent on vertical position within the intertidal zone. Common acorn barnacles (Balanus glandula) have a wide vertical distribution in the intertidal, creating large differences in microhabitat between the highest and lowest individuals in the population. This study set out to explore whether tidal position dependent differences exist in the response to oxygen and desiccation stress in B. glandula. …

Hydric Physiology Of Lizards, Savannah Weaver

Master's Theses

Chapter 1: Animals can respond to extreme climate by behaviorally avoiding it, or by physiologically coping with it. We understand behavioral thermoregulation and physiological thermal tolerances, but water balance has largely been neglected. Climate change includes both global warming and changes in precipitation regimes, so improving our understanding of organismal water balance is increasingly urgent. We assessed the hydric physiology of endangered Blunt-nosed Leopard Lizards (Gambelia sila) by measuring cutaneous evaporative water loss (CEWL), plasma osmolality, body mass, and body condition throughout their active season. On average, G. sila had low CEWL that is likely desert-adaptive, and high …

Southern Sea Otter (Enhydra Lutris Nereis) Fur Morphology, Thermal Function, And Buoyancy Across Ontogeny, Kate Riordan

Master's Theses

Sea otters (Enhydra lutris) have the densest fur of any animal, and the hairs function to trap a layer of air that is used for insulation. When a sea otter is born, it has a natal pelage (baby fur), and sea otters eventually molt that fur and replace it with a pelt resembling the adult fur. Sea otter fur is composed of 3 types of hairs: underhairs, intermediate hairs, and guard hairs. Sea otters are more susceptible to the negative effects of oiling from oil spills compared to other marine mammal species because they solely rely on fur …

Habitat Heterogeneity Affects The Thermal Ecology Of The Federally Endangered Blunt-Nosed Leopard Lizard, Nicole Gaudenti

Master's Theses

Global climate change is already contributing to the extirpation of numerous species worldwide, and sensitive species will continue to face challenges associated with rising temperatures throughout this century and beyond. It is especially important to evaluate the thermal ecology of endangered ectotherm species now so that mitigation measures can be taken as early as possible. A recent study of the thermal ecology of the federally endangered Blunt-Nosed Leopard Lizard (Gambelia sila) suggested that they face major activity restrictions due to thermal constraints in their desert habitat, but that large shade-providing shrubs act as thermal buffers to allow them …

Effects Of Intertidal Position On Metabolism And Behavior In The Acorn Barnacle, Balanus Glandula, Kali Horn

Master's Theses

The intertidal zone is characterized by persistent, tidally-driven fluctuations in both abiotic (e.g., temperature, [O₂], salinity) and biotic (e.g., food availability, predation) conditions, which makes this a very physiologically challenging habitat for resident organisms. The magnitude and degree of variability of these environmental stressors differs between intertidal zones, with the most extreme physiological stress often being experienced by organisms in the high intertidal. Given that many of the fluctuating conditions in this environment are primary drivers of metabolic rate (e.g., temperature, [O₂], food availability), we hypothesized that sessile conspecifics residing in different tidal zones would exhibit …

The Proteomic Response Of Northern Elephant Seal (Mirounga Angustirostris) Pups To Physiological Stress During Development, Melissa P. Voisinet

Master's Theses

Background: Northern elephant seals transition from terrestrial nursing pups to pelagic foraging juveniles in a short period of just 8-12 weeks. During the post-weaning period, pups rely solely on the energy reserves gained during nursing for their caloric demands and water supply. The prolonged absence of food after weaning is the first of many fasts for which the seals have evolved adaptations such as decreased urine production and increased blubber reserves. The stressors experienced from learning to dive for the first time are also stressors that they will experience frequently as an adult and for which they have evolved adaptations. …

Comparative Thermal Ecology Of Coastal And Inland Pacific Rattlesnakes (Crotalus Oreganus), Hayley Layne Crowell

Master's Theses

Global biodiversity is declining as a direct result of anthropogenic climate change. Ectothermic species have become focal organisms for studying the ecological effects of altered climates due to the clear relationship between environmental temperatures and ectotherms’ basic physiological functions. Historically, examinations of these effects have focused heavily on heliothermic lizards, and most others have tended to focus on single populations or sympatric species within a single community. Addressing the longterm energetic implications of environmental temperature variation will provide valuable insight into the cascading physiological effects that certain populations or species may experience as a result of altered climates.

In this …

The Thermal Ecology Of Sceloporus Occidentalis, Luis Patricio Burgos

Master's Theses

With temperatures rising globally, assessing the possible impacts of the changing climate becomes more and more urgent. Ectotherms are excellent indicators of potential climatic ramifications on biodiversity because of their heavy reliance on the environment for their thermoregulation. Studies have historically looked at thermal tolerance values to establish predictive models for population and species extinctions.

In chapter 1, we looked at recent studies that suggest that thermal tolerance may be a plastic trait and test the effects empirically. Most studies are based on captive lizards acclimated to laboratory conditions that do not necessarily reflect natural environments, and if thermal tolerance …

Physiological Response Of The Giant Acorn Barnacle, Balanus Nubilus, To Air Exposure, Emily Jane Resner

Master's Theses

The giant acorn barnacle, Balanus nubilus, is a resident of the subtidal and low intertidal rocky shoreline on the Pacific Coast of North America (Alaska to Baja California). B. nubilusis notable for having the largest muscle fibers in the animal kingdom; fiber diameters that can exceed 3mm in adults! At such extreme sizes these muscle cells may be at risk for insufficient oxygen delivery to mitochondria owing to low SA:V ratios and long intracellular diffusion distances. Oxygen limitation to these muscles may be further exacerbated during low tide air exposure (emersion) or environmental hypoxia events, which are increasing …

Comparative Proteomics: Assessing The Variation In Molecular Physiology Within The Adductor Muscle Between Mytilus Galloprovincialis And Mytilus Trossulus In Response To Acute Heat Stress, Joshua Scott Mier

Master's Theses

Increases in seawater temperatures have imposed physiological constraints which are partially thought to contribute to recently observed shifts in biogeographic distribution among closely related intertidal ectotherms. For instance, Mytilus galloprovincialis an introduced warm-adapted species from the Mediterranean, has displaced the native cold-adapted congener, M. trossulus, over large latitudinal expanses off the California coast. Several comparative physiological studies have revealed interspecific differences in thermal tolerance, including variation in aerobic metabolism and gape behavior, which suggest the invasive congener is better adapted to acclimate to increasing seawater conditions as predicted due to climate change. However, current analyses seek to discover the …

Proteomic Analysis Of The Crustacean Molting Gland (Y-Organ) Over The Course Of The Molt Cycle, Talia B. Head

Master's Theses

Molting in crustaceans is a highly complex physiological process involving negative regulation by two paired endocrine glands, the X-organ/sinus gland complex (XO/SG) and the Y-organ (YO). The XO/SG complex is responsible for making molt-inhibiting hormone (MIH) which negatively regulates synthesis of the molting hormones, ecdysteroids, by the YO. Analysis of gene expression in the XOs and YOs has led to the development of a proposed molecular signaling pathway which regulates ecdysteroidogenesis and subsequent molting in crustaceans. In this study, changes in protein abundance in the YO were characterized over the course of a molt cycle (intermolt, early premolt, mid premolt, …

The Insulin-Like Growth Factor-1 (Igf1) System As A Potential Biomarker For Nutritional Status And Growth Rate In Pacific Rockfish (Sebastes Spp.), Nicole L. Hack

Master's Theses

Growth performance in vertebrates is regulated by environmental factors including the quality and quantity of food, which influences growth via endocrine pathways such as the growth hormone (GH) / insulin-like growth factor somatotropic axis. In several teleost fishes, circulating concentrations of insulin-like growth factor-1 (Igf1) correlate positively with growth rate, and it has been proposed that plasma Igf1 levels may serve as an indicator of growth variation for fisheries and aquaculture applications. Here, I tested whether plasma Igf1 concentrations might serve as an indicator of somatic growth in olive rockfish (Sebastes serranoides), one species among dozens of rockfishes …

Araucaria In The Urban Landscape: A Novel Leaning Pattern And Evidence Of Cultivated Hybridization, Jason W. Johns

Master's Theses

Our understanding of the natural world is constantly evolving and strengthening as more observations are made and experiments are performed. For example, we understand that tree stems grow toward the light (positive phototropism; Darwin 1880, Loehle 1986, Christie et al. 2013) and against gravity (negative gravitropism; Knight 1806, Hashiguchi et al. 2013). We also know that plants respond to mechanical stimulus and perturbation (thigmotropism; Braam 2005). Genes and their resulting proteins have been described to uncover some of the mechanisms for these environmental responses, but relatively speaking, we have just scratched the surface (Wyatt et al. 2013). While the discovery …

Effect Of Oxygen-Limiting Tidal Conditions On Muscle Metabolism And Structure In The Giant Acorn Barnacle, Balanus Nubilus, Katie O. Grady

Master's Theses

Crustacean muscle fibers are some of the largest cells in the animal kingdom, with fiber diameters in the giant acorn barnacle (Balanus nubilus) exceeding 3 mm. Sessile animals with extreme muscle sizes and that live in the hypoxia-inducing intertidal zone – like B. nubilus – represent ideal models for probing the effects of oxygen limitation on muscle cells. We investigated changes in metabolism and structure of B. nubilus muscle in response to: normoxic immersion, anoxic immersion, or air emersion, for acute (6h) or chronic (6h exposures twice daily for 2wks) time periods. Following exposure, we immediately measured hemolymph …

The Proteomic Response Of Gill Tissue In Tidally And Subtidally-Acclimated California Mussels, Mytilus Californianus, To Acute Emersion-Induced Anoxia, Aubrie N. Fowler, Lars Tomanek

Master's Theses

Intertidal mussels regularly experience emersion-induced anoxia, in contrast to normoxic conditions experienced during submersion. We therefore hypothesized that acclimation to a tidal rhythm, as opposed to a rhythm of constant submersion, preconditions the proteome of the California mussel, Mytilus californianus, to respond differently to emersion-induced anoxia. Following acclimation, mussels either continued to receive the acclimation conditions (control) or were exposed to 100% nitrogengas (anoxia) during aerial emersion. We collected gill tissue for subsequent analysis of protein abundance with 2D gel electrophoresis and protein identification with tandem mass spectrometry. Relative to subtidally-acclimated mussels, tidally-acclimated mussels showed a greater propensity to …

Stress Ecology Of The Pacific Rattlesnakes (Crotalus Oreganus And Crotalus Helleri), Natalie Claunch

Master's Theses

Stress is a physiological state induced by disturbance or adverse environmental conditions and is modulated by the glucocorticoid hormone corticosterone (CORT) in reptiles. Stressors can have various impacts on vertebrate trait expression and may affect survival or reproduction. Little is known about the effects of chronically elevated CORT in free-ranging reptiles, or the effect of disturbance stress on venom composition in captive snakes.

In chapter 1, we investigated the effects of researcher induced disturbance on CORT levels and venom composition in a group of captive Northern Pacific rattlesnakes (Crotalus oreganus). Venom protein concentration and plasma CORT levels were …

Effects Of Supplemental Hydration On Physiology And Behavior Of Northern Pacific Rattlesnakes (Crotalus Oreganus Oreganus), Griffin D. Capehart

Master's Theses

Hydration is a critical element for many physiological processes in vertebrates, such as protein production, innate immunity, and behavioral processes such as daily activity and thermoregulation. Few studies have directly assessed the effect of hydration on these animals in nature. While it seems intuitive that drought is stressful to animals, studies examining drought are typically observational and fail to assess how the hydration state of these animals influences their physiology and behavior. We tested for an effect of hydration on several physiological and behavioral parameters in Northern Pacific rattlesnakes (Crotalus oreganus oreganus) by experimentally manipulating hydration levels in …

Multi-Stress Proteomics: The Global Protein Response To Multiple Environmental Stressors In The Porcelain Crab Petrolisthes Cinctipes, Michael A. Garland

Master's Theses

Global climate change is increasing the number of hot days along the California coast as well as increasing the incidence of off-shore upwelling events that lower the pH of intertidal seawater; thus, intertidal organisms are experiencing an increase in more than one stress simultaneously. This study seeks to characterize the global protein response of the eurythermal porcelain crab Petrolisthes cinctipes to changes in thermal, pH, and tidal regime treatments, either combined or individually. The first experiment examined temperature stress alone and sought to determine the effect of chronic temperature acclimation on the acute heat shock response. We compared the proteomic …

A Comparison Of Fatigue During Cardiocerebral Resuscitation With Different Compression Rates Among Layperson And Professional Rescuers, Christopher Cassidy

Master's Theses

Quality chest compressions during Cardiopulmonary Resuscitation (CPR) are vital to maintaining adequate perfusion of oxygenated blood to the organs of the body to sustain life. Over the years, the compression rate recommended in Basic Life Support (BLS)/ Advanced Cardiac Life Support (ACLS) protocols for the best possible outcome has risen, and with that increase there are questions regarding rescuer fatigue and the effectiveness of compressions. Layperson and professional rescuers, answering to an emergency, both maintain continuous chest compressions until advanced life support arrives. Depending on the location, this arrival time would most likely be longer than the two minute standard …

Variability Of Practice And Strength Training Periodization: When Theories Collide, Katherine Lauren Streder

Master's Theses

The primary purpose of this study was to examine whether variability of practice enhances neuromuscular adaptations when compared to traditional strength training. The secondary purpose was to investigate whether there was a difference in perception of exertion between the two strength programs. Forty one subjects (23 women and 18 men) were assigned to either the control group or one of two treatment groups by a blocked-random method. Subject's one repetition maximum (1RM) for the kettlebell press and leg press were measured at baseline, after 4 weeks of training, and after 8 weeks of training. The treatment groups completed 8 weeks …

Associations Between Alcohol Consumption And Fasting Blood Glucose In Young Adults, Julie Ann Lucca

Master's Theses

Current research shows moderate alcohol consumption is associated with decreased risk of diabetes and excessive consumption or binge drinking can cause insulin resistance and diabetes. In 2010, diabetes was the seventh leading cause of death in the United Statesand was responsible for significant health complications: blindness, kidney failure, and limb amputations, and is a large national economic burden. Fasting blood glucose (FBG) is a tool used to help diagnose diabetes. Abnormally high FBG, ≥100 mg/dl, is indicative of diabetes and pre-diabetes. Few studies have observed diabetic prevalence among young adults or college students. Studying young adults can help provide added …

House Finches, Carpodacus Mexicanus: Hormones, Stress, And Song Control Regions, Katherine Olivia Ganster

Master's Theses

Song production in songbirds is controlled by parts of the brain known as the song control regions (SCRs). During spring, gonads increase in size, males sing to attract mates, and SCRs become larger. This neuroplasticity is controlled by the change in day length and increased plasma testosterone (T) levels. Plasma T can be reduced by stress through the production of corticosterone (CORT), through the production of beta-endorphin, or through direct effects on the testes via the nervous system. We determined the T, estradiol, and CORT hormonal profiles of wild House Finches by capturing and sampling blood from the finches every …

The Proteomic Response Of Sea Squirts (Genus Ciona Congeners) To Hyposalinity Stress, James S. Koman

Master's Theses

The ascidian species Ciona savignyi and C. intestinalis are invasive species but show interspecific differences in their population response to hypo-saline stress associated with heavy winter-run off events that are predicted to become more frequent due to climate change. Despite an almost world-wide distribution, C. intestinalis seems to be more susceptible to hypo-saline stress than the geographically more limited C. savignyi. Given that the genomes of both species are fully sequenced, we were able to compare their proteomic response to both acute and chronic salinity to characterize the mechanisms that are responsible for setting tolerance limits to hyposaline conditions …

Impact Of Collateral Enlargement On Smooth Muscle Phenotype, Alexander Jerome Bynum

Master's Theses

Peripheral Artery Disease is a very serious disease characterized by an arterial occlusion due to atherosclerotic plaques. In response to an arterial occlusion, arteriogenesis occurs, causing smooth muscle cells to transition from a contractile to synthetic state. Also following an arterial occlusion, functional impairment was seen in the collateral circuit. An immunofluorescence protocol was developed in order to assess the impact of collateral enlargement (arteriogenesis) on smooth muscle phenotype at various time points. Smooth muscle α-actin was used to mark all smooth muscle cells, Ki-67 was used to label proliferating smooth muscle cells, and a fluorescent nuclear stain was used …

Ischemia Impairs Vasodilation In Skeletal Muscle Resistance Artery, Kyle Remington Struthers

Master's Theses

Functional vasodilation in arterioles is impaired with chronic ischemia. We sought to examine the impact of chronic ischemia and age on skeletal muscle resistance artery function. To examine the impact of chronic ischemia, the femoral artery was resected from young (2-3mo) and adult (6-7mo) mice and the profunda femoris artery diameter was measured at rest and following gracilis muscle contraction 14 days later using intravital microscopy. Functional vasodilation was significantly impaired in ischemic mice (14.4±4.6% vs. 137.8±14.3%, p<0.0001 n=8) and non-ischemic adult mice (103.0±9.4% vs. 137.8±14.3%, p=0.05 n=10). In order to analyze the cellular mechanisms of the impairment, a protocol was developed to apply pharmacological agents to the experimental preparation while maintaining tissue homeostasis. Endothelial and smooth muscle dependent vasodilation were impaired with ischemia, 39.6 ± 13.6% vs. 80.5 ± 11.4% and 43.0 ± 11.7% vs. 85.1 ± 10.5%, respectively. From this data, it can be supported that smooth muscle dysfunction is the reason for the observed impairment in arterial vasodilation.

Acute Nitrate Exposure Causes Proteomic Changes Consistent With The Regulation Of Reactive Oxygen And Nitrogen Species, Lauren R. Hitt, Lars Tomanek

Master's Theses

Nitrate is the most common ionic form of nitrogen in aquatic ecosystems. Although nitrate is known to affect ecosystems at high levels through eutrophication, hypoxia and loss of biodiversity, it is considered to be physiologically inert to the individual aquatic organism. To test the physiological effects of nitrate on aquatic life, we exposed gill tissue of the Pacific oyster, Crassostrea gigas, to nitrate and characterized changes in protein expression, using a gel-based proteomics approach. Of the 642 protein spots detected, we found that 24 proteins (15 identified) changed expression in response to a 6-hour exposure to nitrate concentrations ranging from …

The Relationship Between Plasma Steroid Hormone Concentrations And The Reproductive Cycle Of The Northern Pacific Rattlesnake, Crotalus Oreganus, Craig Michael Lind

Master's Theses

To gain a better understanding of the role of steroid hormones in vertebrate reproduction, we quantified steroid hormone concentrations in a free ranging population of the Northern Pacific rattlesnake, Crotalus oreganus. Plasma steroid hormone concentrations were quantified for both male and female snakes throughout the active season (Mar-Oct). We measured testosterone (T), 5α-dihydrotestosterone (DHT), and corticosterone (B) concentrations in male and female snakes. 17β-estradiol (E2) and progesterone (P) were measured in females only. We also observed breeding behaviors (e.g. consortship, courtship, and copulation) in the field and measured testis and follicle size in male and female snakes from museum collections. …