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Song As An Honest Indicator Of Developmental Stress In Song Sparrows, Kimberly L. Schmidt Dec 2013

Song As An Honest Indicator Of Developmental Stress In Song Sparrows, Kimberly L. Schmidt

Electronic Thesis and Dissertation Repository

The Developmental Stress Hypothesis proposes that the honesty of birdsong is maintained by costs incurred during development, such that song in adulthood reflects exposure to early-life stressors. The purpose of this thesis was to provide a rigorous test of the Developmental Stress Hypothesis in song sparrows (Melospiza melodia). My three objectives were to determine the long-term effects of early-life stress on: 1) physiological traits (Chapters 2, 3, and 4); 2) male song production (Chapter 5); and 3) the response of females to song (Chapter 6). Nestlings were hand-reared in captivity under one of three treatment conditions: control, food restriction, or ...


A Comparison Of Salmonella Enterica Serovars: Are Prevalence, Virulence And Responses To Environmental Conditions Serovar Or Strain Dependent?, Nan Zhang Aug 2013

A Comparison Of Salmonella Enterica Serovars: Are Prevalence, Virulence And Responses To Environmental Conditions Serovar Or Strain Dependent?, Nan Zhang

Masters Theses

Salmonella are considered the leading cause of foodborne illnesses with frequent outbreaks in United States. While more than 2500 serovars have been identified, Salmonella Typhimurium and Salmonella Enteritidis are primarily responsible for most human infections while Salmonella Kentucky and Salmonella Heidelburg are currently the most prevalent serovars associated with poultry contamination. The relationship between virulence and prevalence is not fully understood, but may be a result of environmental stress exposure such as acid stress. In this research, organic acid (acetate) and inorganic acid (hydrogen chloride) were applied to 15 different serovars isolated from human infections or poultry. The growth curves ...


The Investigation Of Risk Factors For Upper Respiratory Infections Among College Students, Romie Barnes May 2013

The Investigation Of Risk Factors For Upper Respiratory Infections Among College Students, Romie Barnes

Honors Theses

Upper respiratory tract infections and cold-like illnesses are common sources of morbidity among college students. The emphasis of hand-washing and reducing the dispersal of aerosol droplets by covering coughs and sneezes reduces the spread of the common cold. However, less emphasis is placed on other risk factors for reducing cold-like illness such as: stress level and physical activity (Doyle and Cohens 2009). An increase in stress and a decrease in physical activity are common among college students (Nichol et al 2005). For this reason, the present study analyzed the effects of stress and physical activity on the incidence of upper ...


The Effect Of Rider Level On Equine Mean Heart Rate At The Trot, Jacqueline Marinoff Apr 2013

The Effect Of Rider Level On Equine Mean Heart Rate At The Trot, Jacqueline Marinoff

Honors Theses and Capstones

The effect of riders at two different levels of riding ability on the mean heart rates (HR) of school horses at the trot was studied. Five horses were each paired with a beginner (n=4) and an intermediate (n=5) rider, and the mean HR generated by the two riders at the trot were compared for each horse. There was a significant (p


Norepinephrine Involvement In The Intermittent Swim Stress-Induced Deficit In Spatial Learning And Memory, Emily Elgert Apr 2013

Norepinephrine Involvement In The Intermittent Swim Stress-Induced Deficit In Spatial Learning And Memory, Emily Elgert

Honors Theses and Capstones

Learning and memory impairments are often caused by stress disorders including depression. The present study investigated the involvement of norepinephrine in the swim stress-induced deficits of spatial learning and memory. Exposure to intermittent swim stress (ISS) followed by learning and memory tests in the Morris water maze (MWM) were used to investigate this relationship. The ISS paradigm consists of intermittent exposure to cold water, producing stress responses in rats. Reboxetine, a norepinephrine selective reuptake inhibitor (NSRI), was employed to investigate whether this compound reverses the ISS-induced deficit. In other words, rats exposed to the ISS, were hypothesized to experience impaired ...


Defining A Role For Inducible Heat Shock Protein 70 (Hsp70i) In Mediating Autoimmune Vitiligo, Jeffrey Alan Mosenson Jan 2013

Defining A Role For Inducible Heat Shock Protein 70 (Hsp70i) In Mediating Autoimmune Vitiligo, Jeffrey Alan Mosenson

Dissertations

Vitiligo is an autoimmune disease characterized by destruction of melanocytes, leaving 0.5% of the population with progressive depigmentation. Current treatments offer limited efficacy. Observations that heat shock proteins (HSPs) can serve as adjuvants in antitumor vaccines first suggested to us a link between HSPs and stress-induced vitiligo. Such proteins are marvelously well conserved throughout evolution, which has placed them in the spotlight for helping to understand the intriguing relationship between infection and immunity. Intracellularly, inducible heat shock protein 70 (HSP70i) is upregulated by stress and helps protect cells from undergoing apoptosis. In times of stress, melanocytes will secrete antigen ...


Stress, Monoamines, And Cognitive Flexibility, Kevin Snyder Jan 2013

Stress, Monoamines, And Cognitive Flexibility, Kevin Snyder

Publicly Accessible Penn Dissertations

Stress has been implicated in psychiatric disorders that are characterized by impaired executive function, which is mediated by the prefrontal cortex (PFC). The stress-related neuropeptide, corticotropin-releasing factor (CRF) regulates monoamine systems that project to the PFC, including the locus coeruleus norepinephrine (LC-NE) system and the dorsal raphe-serotonin (DRN-5-HT) system. CRF actions on these systems may underlie cognitive symptoms of stress-related disorders. The age at which stress occurs can determine its impact, and adolescent stress has been linked to adult psychopathology. This dissertation explores the role of CRF in stress-induced modulation of the LC-NE and DRN-5-HT systems and the developmental time ...


Regulation And Dynamic Behavior Of The Heat Shock Transcription Factor Hsf-1 In C. Elegans, Elizabeth A. Morton Jan 2013

Regulation And Dynamic Behavior Of The Heat Shock Transcription Factor Hsf-1 In C. Elegans, Elizabeth A. Morton

Publicly Accessible Penn Dissertations

Eukaryotic cells respond to heat stress by activating the transcription factor HSF1. In addition to its role in stress response, HSF1 also functions in protein homeostasis, aging, innate immunity, and cancer. Despite prominent HSF1 involvement in processes pertinent to human health and disease, there are still gaps in our understanding of HSF1. For example, controversy exists regarding the localization of HSF1, the identity of HSF1 regulators, and the function and conservation of heat-induced HSF1 stress granules. Many of the physiological roles for HSF1 have been defined using the model organism Caenorhabditis elegans, yet little is known about how the molecular ...


The Effects Of Multiple Abiotic Stressors On The Susceptibility Of The Seagrass Thalassia Testudinum To Labyrinthula Sp., The Causative Agent Of Wasting Disease, Nichole Danielle Bishop Jan 2013

The Effects Of Multiple Abiotic Stressors On The Susceptibility Of The Seagrass Thalassia Testudinum To Labyrinthula Sp., The Causative Agent Of Wasting Disease, Nichole Danielle Bishop

UNF Graduate Theses and Dissertations

In the past century, seagrasses have experienced massive die off episodes in what has been collectively referred to as “wasting disease.” Researchers generally agree that wasting disease is caused by a protist of the Labyrinthula genus, and that environmental stressors can make some populations of seagrasses more susceptible to infection. The purpose of this study was to examine the combined effects of elevated salinity, elevated temperature, elevated sulfide and night-time hypoxia on Thalassia testudinum health and its response to Labyrinthula sp. infection under controlled conditions. To test these effects, microcosms were utilized and individual seagrass shoots were randomly assigned to ...


The Association Of Physical Fitness With Psychological Health Outcomes In Soldiers During Army Basic Combat Training, Shannon K. Crowley Jan 2013

The Association Of Physical Fitness With Psychological Health Outcomes In Soldiers During Army Basic Combat Training, Shannon K. Crowley

Theses and Dissertations

Despite the current need for investigation of factors involved with soldiers' resilience to stressors in the Basic Combat Training (BCT) environment, and evidence in civilian populations that physical training is associated with psychological benefits, little is known about the relationship between physical fitness and psychological adjustment during BCT. Study one of this dissertation involved an extensive literature review of factors related to the relationship between physical fitness and psychological adjustment of soldiers during BCT. Using qualitative focus group methods, study two assessed soldiers' perceptions about their sleep, and consequences of sleep disruption during BCT at Fort Jackson in Columbia, SC ...