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Theses and Dissertations

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Full-Text Articles in Life Sciences

Evaluation Of Downy Mildew (Peronospora Farinosa F.Sp. Chenopodii) Resistance Among Quinoa Genotypes And Investigation Of P. Farinosa Growth Using Scanning Electron Microscopy, Leilani Kitz Jul 2008

Evaluation Of Downy Mildew (Peronospora Farinosa F.Sp. Chenopodii) Resistance Among Quinoa Genotypes And Investigation Of P. Farinosa Growth Using Scanning Electron Microscopy, Leilani Kitz

Theses and Dissertations

Quinoa (Chenopodium quinoa Willd.) is a pseudocereal native to the Andean region of South America and a staple crop for subsistence farmers in the altiplano of Bolivia and Peru. Downy mildew is the most significant disease of quinoa caused by the pathogen Peronospora farinosa f.sp. chenopodii Byford. This disease greatly impacts quinoa crops with yield losses up to 99%. As fungicides are expensive for farmers, the development of resistant cultivars appears to be the most efficient means for controlling downy mildew. The quinoa germplasm bank contains high amounts of genetic diversity, some of which exhibit mildew resistance. Methods for evaluating …

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Investigating And Modeling Possible Mechanisms By Which Healthy Cell Membranes Become Resistant To Hydrolysis By Secretory Phospholipase A2, Jennifer Nelson Jul 2008

Investigating And Modeling Possible Mechanisms By Which Healthy Cell Membranes Become Resistant To Hydrolysis By Secretory Phospholipase A2, Jennifer Nelson

Theses and Dissertations

Secretory phospholipase A2 (sPLA2) behaves differently toward the membranes of healthy cells compared to those of damaged or dying cells. The enzyme catalyzes rapid and sustained hydrolysis of compromised cells consistent with a simple catalytic mechanism. In contrast, when healthy cells are incubated with sPLA2, they become resistant to hydrolytic attack as manifest by three unusual observations: First, hydrolysis is transient and represents only a small fraction of the total membrane phospholipid content. Second, subsequent addition of sPLA2 fails to generate additional product. Third, the apparent potency of the enzyme to cause the membrane to be refractory is much greater …

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A Comparative Analysis Of Hydrolysis Kinetics By Spla2 Isoforms During Apoptosis In S49 Cells, Erin Dalene Olson Jul 2008

A Comparative Analysis Of Hydrolysis Kinetics By Spla2 Isoforms During Apoptosis In S49 Cells, Erin Dalene Olson

Theses and Dissertations

Secretory Phospholipase A2 (sPLA2) represents a diverse class of roughly 20 enzymes, 12 of which have been identified in humans. These isoforms can be distinguished based on their tissue distribution, structure, and regulation. These differences in structure between the isoforms lead to the question does the enzyme's ability to respond to physical changes in the membrane during apoptosis governed by structure. S49 cell apoptosis was initiated by treatment with either the glucocorticoid dexamethasone (6–48 h) or with the calcium ionophore, ionomycin. The rates of hydrolysis were compared with each treatment condition for various concentrations of snake venom and human groups …

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Studies On Transformation Of Tomato(Solanum Lycopersicum L.) And Arabidopsis Thaliana Using Chimerical Constructs Of Varying Tospoviral Origin, Joshua Nathaniel Cobb Jul 2008

Studies On Transformation Of Tomato(Solanum Lycopersicum L.) And Arabidopsis Thaliana Using Chimerical Constructs Of Varying Tospoviral Origin, Joshua Nathaniel Cobb

Theses and Dissertations

Pathogen derived resistance (PDR) is a recent breakthrough where plant hosts can be made to be resistant to viral infections through transformation with conserved viral genes. Given the severity of Tospovirus diseases worldwide (particularly in tomato), PDR has the potential to garner large yield returns where pathogen populations have overcome the established resistance. Tomato breeding lines FLA7804, FLA8044, and the research line MP1 were used in transformation experiments with potions of the Tomato spotted wilt virus (TSWV) N-gene, and two other chimerical viral nucleocapsid gene constructs from, Impatiens necrotic spot virus (INSV), and Groundnut ringspot virus (GRSV). We conducted 19 …

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Reasons For Physical Activity And Exercise Participation In Senior Athletes, Deborah Lynne Fife Jul 2008

Reasons For Physical Activity And Exercise Participation In Senior Athletes, Deborah Lynne Fife

Theses and Dissertations

Research on physical activity and exercise in the elderly is limited. This study used the Participation Motivation Questionnaire for Older Adults (PMQOA) to assess reasons for engaging in regular physical activity of participants at the 2007 Huntsman World Senior Games. The 259 subjects ranged from ages 50 to 85 years and were divided into tertiles based on frequency of exercise, determined by self reported weekly exercise time and days for further comparison. The most commonly reported reasons for exercise were to stay healthy, keep physically fit, and stay in shape. A previously conducted factor analysis on the PMAOQ revealed six …

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Comparative Cytotoxicity Of An Fda-Approved Cancer Drug To Extracts Of Atriplex Confertifolia On Human Breast And Cervical Cancer Cells, Christopher James Capua Jul 2008

Comparative Cytotoxicity Of An Fda-Approved Cancer Drug To Extracts Of Atriplex Confertifolia On Human Breast And Cervical Cancer Cells, Christopher James Capua

Theses and Dissertations

The severity and number of people affected by cancer is a worldwide problem with millions of people affected annually. The search for treatment and cures of cancer continues to be a global effort. As part of this global effort, many natural products have been tested against cancer cell lines, most from plants located in tropical regions. However, this study reports that extracts of Atriplex confertifolia, a native North American plant, has significant bioactivity against human breast cancer cell lines MCF-7, 435, and 231, and HeLa cells (cervical cancer cells). The bioactivity of A. confertifolia extracts of these cells lines was …

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The Role Of Microrna-155 And Microrna-146a As Putative Oncomirs In The Tumor Progression Of Prostate Cancer, Jennifer Hoyt Jul 2008

The Role Of Microrna-155 And Microrna-146a As Putative Oncomirs In The Tumor Progression Of Prostate Cancer, Jennifer Hoyt

Theses and Dissertations

Prostate cancer is the most common cancer occurring in males. The identification of novel microRNAs (miRs) that contribute to tumor progression represents prospective treatment targets. miRs are small non-coding RNAs important in gene regulation with specific tissue expression patterns. Each miR is thought to affect the expression of hundreds of different RNA targets. Two putative oncomiRs, miR-155 and miR-146a, were shown to be differentially expressed in the human derived, prostate cell sublines M12 and F6. Quantification of endogenous miR expression showed high levels in the metastatic M12 cell line versus low in its weakly tumorigenic F6 variant. The restoration of …

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Genetic Analysis Of The Role Of Smpb In Establishing The Reading Frame On Tmrna, Talina Christensen Watts Jul 2008

Genetic Analysis Of The Role Of Smpb In Establishing The Reading Frame On Tmrna, Talina Christensen Watts

Theses and Dissertations

Ribosomes translate the genetic information encoded by mRNA into proteins. Defective mRNAs can cause stalling of translating ribosomes. The molecule tmRNA (transfer-messenger RNA) rescues stalled ribosomes in eubacteria. Together with its protein partner SmpB, tmRNA mimics a tRNA by entering the ribosomal A site and linking an alanine residue to the growing polypeptide chain. The ribosome then abandons the defective mRNA template and resumes translation on tmRNA, adding ten more amino acids to the nascent polypeptide. As a result of tmRNA action, stalled ribosomes are released and recycled, the defective mRNA is destroyed, and the aborted protein product is tagged …

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Percent Body Fat And Fat Distribution Are Not Associated With Carotid Artery Intima-Media Thickness In Healthy Middle-Aged Women, Kayleen Adams Goff Jul 2008

Percent Body Fat And Fat Distribution Are Not Associated With Carotid Artery Intima-Media Thickness In Healthy Middle-Aged Women, Kayleen Adams Goff

Theses and Dissertations

Background and Purpose – The relationship between abdominal body fat and cardiovascular health is not completely understood. This study investigated the association between percent body fat, fat distribution and intima-media thickness (IMT) in healthy middle-aged women.
Methods – 224 middle-aged (mean age = 43.1 years ± 3.0), nonsmoking women were included in this study. The women were assessed with a B-mode, high-resolution ultrasonograph to measure the intima-media thickness of the right common carotid artery (CCA). Measurements for percent body fat and fat distribution were assessed using Bod Pod and waist circumference (WC) measured at the umbilicus, respectively.
Results – Data …

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Effects Of Same-Day Strength Training On Bat Swing Velocity Of Male Collegiate Baseball Players, Anthony Loren Clah Jul 2008

Effects Of Same-Day Strength Training On Bat Swing Velocity Of Male Collegiate Baseball Players, Anthony Loren Clah

Theses and Dissertations

The purpose of this study was to investigate the effect of same-day strength training on bat swing velocity of male collegiate baseball players. Sixteen male baseball players engaged in a preseason strength training program designed by the team's strength and conditioning coach. All subjects were tested for bat swing peak velocity immediately prior to ball impact for a non lifting day (NLD) by recording 10 swings with 30 seconds of rest in between swings. The next day, a lifting day (LD), all subjects tested on the NLD were tested four to six hours after the morning lifting session with the …

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Ion Permeation Through Membrane Channels: Molecular Dynamics Simulations Studies, Morad Mustafa Jul 2008

Ion Permeation Through Membrane Channels: Molecular Dynamics Simulations Studies, Morad Mustafa

Theses and Dissertations

Molecular dynamics simulation was used to study ion permeation through different membrane proteins embedded in a lipid bilayer (DMPC) with different saline solutions. The potential of mean force (PMF) for ion transport was obtained by umbrella sampling simulations. A revised MacKerell force field for tryptophan residues was studied using gramicidin A (gA) channel as a test model. The revised force field contribution to the Na+ PMF was consonant with the prediction from the experimental results, but in stark contrast to the prediction of the CHARMM force field, version 22, for the tryptophan side-chain. A new grid-based correction map algorithm by …

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Characteristics Of Volunteer Leaders In The American Dietetic Association Compared To Non-Volunteer Registered Dietitians, Samantha Payne Rasmussen Jul 2008

Characteristics Of Volunteer Leaders In The American Dietetic Association Compared To Non-Volunteer Registered Dietitians, Samantha Payne Rasmussen

Theses and Dissertations

Objective To identify characteristics of dietitians who serve as leaders in the American Dietetic Association (ADA) and their managers, and to compare them to registered dietitians not in volunteer leadership roles and their managers.
Design A cross-sectional survey of volunteer leaders and those who have never volunteered as leaders in ADA.
Subjects/setting The study sample included elected officers in ADA and executive board members of ADA state affiliates (volunteer leaders) (n=259) and their managers (n=115), as well as a sample of registered dietitians not in ADA leadership roles (control) (n=273) and their managers (n=221).
Statistical analyses performed The variables examined …

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Competitive Exclusion Of Cyanobacterial Species In The Great Salt Lake, Hillary Christine Roney Jul 2008

Competitive Exclusion Of Cyanobacterial Species In The Great Salt Lake, Hillary Christine Roney

Theses and Dissertations

Under Gause's principle two species cannot indefinitely occupy the same niche. The north and south arms of Great Salt Lake are separated by a rail causeway, resulting in salinity differences and color variation between the arms. Farmington Bay is also separated from the south arm by a vehicular causeway to Antelope Island. These causeways allow examination of competitive exclusion of cyanobacteria in the hypersaline environment of the Great Salt Lake. Cyanobacterial distributions partially map salinity, with Aphanothece halophytica proliferating in the north arm, and Nodularia spumigena in the south arm. I hypothesized that cyanobacterial species abundant north of the railway …

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Not By Commandment Or Constraint: The Relationship Between The Dietary Behaviors Of College-Aged Latter-Day Saints And Their Interpretation Of The Word Of Wisdom, Rick B. Jorgensen Jul 2008

Not By Commandment Or Constraint: The Relationship Between The Dietary Behaviors Of College-Aged Latter-Day Saints And Their Interpretation Of The Word Of Wisdom, Rick B. Jorgensen

Theses and Dissertations

Latter-day Saints are recognized throughout the world by their peculiar dietary code known as the Word of Wisdom. It is accepted by the Church as revelation and contains both proscriptions and prescriptions. Different levels of interpretation, understanding and observance of the principles in the Word of Wisdom make it a unique Latter-day Saint religious health code. The study population consists of college-aged male and female members of The Church of Jesus Christ of Latter-day Saints from Brigham Young University and a Latter-day Saint student stake affiliated with Utah Valley University. A questionnaire was conceptualized, designed and validated over a one …

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Using A Chelator-Buffered Nutrient System To Study Phosphorus, Manganese And Zinc Interactions In Russet Burbank Potato, Steven A. Barben Jul 2008

Using A Chelator-Buffered Nutrient System To Study Phosphorus, Manganese And Zinc Interactions In Russet Burbank Potato, Steven A. Barben

Theses and Dissertations

Potato production requires high phosphorus (P) application with potential negative environmental or nutritional consequences for potato as well as for subsequent crops. Impacts of high available P on yield and plant nutrition of species in potato cropping rotations are inadequately understood, and could result in antagonistic interactions with cationic micronutrients such as zinc (Zn) and manganese (Mn). Three hydroponic experiments were conducted with Russet Burbank potato to elucidate P and Zn relationships and associated interactions with other nutrients. In the first experiment, P solution concentration was constant at 256 µM while Zn concentration varied: 0.1, 2, 6, 18, 54, 162 …

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Effect Of Ca And Ph On Disease Severity Of Pink Rot Phytophthora Erythroseptica In Russett Norkotah Potato Solanum Tuberosum, Jared H. Benson Jul 2008

Effect Of Ca And Ph On Disease Severity Of Pink Rot Phytophthora Erythroseptica In Russett Norkotah Potato Solanum Tuberosum, Jared H. Benson

Theses and Dissertations

Phytophthora erythroseptica Pethyb. is a devastating fungal pathogen of potato (Solanum tuberosum). The pathogen causes a disease known as pink rot. Pink rot results in necrosis and decay of tubers; and is responsible for major losses pre and post harvest. Attributes of the disease are progressing toward epidemic proportions. To help prevent such dramatic outbreaks of the disease, understanding the factors associated with incidence will provide opportunities to control the pathogen. A link between pH and disease severity has been observed. We studied the effects of pH and Ca to determine their influence on disease development. Low pH and Ca …

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Pygmy Rabbit (Brachylagus Idahoensis) Habitat Use, Activity Patterns And Conservation In Relationship To Habitat Treatments, Janet E. Lee Jun 2008

Pygmy Rabbit (Brachylagus Idahoensis) Habitat Use, Activity Patterns And Conservation In Relationship To Habitat Treatments, Janet E. Lee

Theses and Dissertations

This study examined activity patterns and habitat use of pygmy rabbits (Brachylagus idahoensis) in mechanically treated and untreated areas in south-central Utah 2005-2008. We monitored fecal pellet plots in continuous sagebrush habitat as well as along treatment edges to record deposition and leporid presence over timed periods. Pygmy rabbit use of big sagebrush was higher than black-tailed jackrabbits (Lepus californicus) and mountain cottontail rabbits (Sylvilagus nuttallii ) (P< 0.01) relative to treated areas (P <0.01). We also compared pygmy rabbit use of areas with continuous sagebrush to residual sagebrush in a sample of mechanically treated areas. Our results suggest a treatment effect with higher (P <0.01) average counts of pygmy rabbit pellets in areas with continuous sagebrush compared to sagebrush strips and islands within treated areas. Before the big sagebrush biotype inhabited by pygmy rabbits is treated to reduce the occurrence and dominance of big sagebrush, we recommend managers consider two options. The first is no treatment, thus preserving, as is, the critical habitat of the pygmy rabbit and other sympatric big sagebrush obligate species of wildlife. The second option cautiously introduces the first prescription of habitat treatment ever recommended in relationship to the pygmy rabbit. This prescription includes recommended widths of the treated areas, seed mixes, widths of the preserved intact big sagebrush habitat for pygmy rabbits as well as suggested grazing systems for domestic livestock. Activity patterns of pygmy rabbits at their burrow were documented through the use of remote cameras. Photographs were analyzed for temporal and seasonal patterns of activity. Our results suggested that time of day was important in the activity level of pygmy rabbits while season was not. Pygmy rabbits were active during all time periods of the day but the greatest levels of activity occurred at night. Numerous other wildlife species were recorded by our remote cameras including other species of leporids, birds, rodents, reptiles and terrestrial predators.

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The Response Of Hn4 Cells To Porphyromonas Gingivalis Dna, Cheyanne Warren Jun 2008

The Response Of Hn4 Cells To Porphyromonas Gingivalis Dna, Cheyanne Warren

Theses and Dissertations

Periodontal disease is one of the most common human diseases. Bacteria trigger the onset and progression of the disease and among them Porphyromonas gingivalis has been demonstrated to be a major etiologic agent. Although the interaction of the bacterium with the host is of major importance for the understanding of the disease mechanisms, both the host as well as the pathogen components involved in the interaction remain poorly understood. One of the bacterial components capable of eliciting a host response is unmethylated CpG DNA motifs found in bacteria. Thus, the first aim was to determine the response of oral epithelial …

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Plumage Ornamentation As An Indicator Of Female Age And An Influence In Male Mate Choice In Protonotaria Citrea, The Prothonotary Warbler In Virginia., Terry Smith Jun 2008

Plumage Ornamentation As An Indicator Of Female Age And An Influence In Male Mate Choice In Protonotaria Citrea, The Prothonotary Warbler In Virginia., Terry Smith

Theses and Dissertations

Flamboyant plumage and ornamentation is common and well-known in male birds; it serves as a sexual display to attract potential mates. While flamboyant plumage is less common and usually more subtle in female birds, it does occur in some species such as Dark-Eyed Juncos (Junco hyemalis) and Prothonotary Warblers (Protonotaria citrea). Prothonotary Warblers display relatively subtle sexual dimorphism. This study examines variations in tail spot patterns in Prothonotary Warblers and relates those variations to age in females. Females with fewer than six spots tend to be two years old or younger; females with six spots or more tend to be …

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Intravenous Administration Of Perfluorocarbon Emulsions As A Non-Recompression Therapy For Decompression Sickness, Cameron Smith Jun 2008

Intravenous Administration Of Perfluorocarbon Emulsions As A Non-Recompression Therapy For Decompression Sickness, Cameron Smith

Theses and Dissertations

Decompression sickness (DCS) results from a sudden decrease in ambient pressure leading to super-saturation of tissues with inert gas and subsequent bubble formation within both tissues and blood. Perfluorocarbons (PFC) are able to dissolve vast amounts of non-polar gases. The administration of intravenous (I.V.) PFC emulsions reduce both morbidity and mortality of DCS, but the mechanism of this protective effect has not yet been demonstrated. Juvenile Dorper cross sheep between 16 and 24 kg (n=31) were anaesthetized and instrumented for physiological monitoring, the administration of I.V. fluids and sampling of arterial and mixed venous blood. Animals were placed in a …

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Motor Function Responses To Induced Pain And Cryotherapy, Blaine Cletus Long May 2008

Motor Function Responses To Induced Pain And Cryotherapy, Blaine Cletus Long

Theses and Dissertations

Objective: Establish and validate an experimental pain model that will create pain for at least 20-minutes and then use the model to determine if: 1) cryotherapy decreases experimentally induced pain, 2) experimentally induced pain contributes to arthrogenic muscle inhibition, and 3) cold application influences pain or arthrogenic muscle inhibition. To answer these questions we conducted two experiments, the results of which are presented in two manuscripts. Methods: Seventy (n = 30 for experiment I and n = 40 for experiment II), physically active healthy male subjects participated. Interventions: Independent variables used for experiment I were condition (5% hypertonic saline infusion/cryotherapy, …

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Effect Of Hemoglobin-Based Oxygen Carriers On Arterial Pressure And Vasoactivity In The Rat Mesentery, Michael Kim May 2008

Effect Of Hemoglobin-Based Oxygen Carriers On Arterial Pressure And Vasoactivity In The Rat Mesentery, Michael Kim

Theses and Dissertations

Hemoglobin-based oxygen carriers provide a promising future as an alternative to human blood transfusions. Hemoglobin-based oxygen carriers, HBOCs, provide a lowcost, easy to maintain, and safe solution. They require no refrigeration and are universally compatible, and the required transfusion volume is less than that of a normal transfusion. HBOCs have been known to have adverse side effects such as renal toxicity, gastrointestinal dismotility, and hypertension. Many of these problems stem from the lack of a membrane, which protects the hemoglobin from dissociating and extravasating into the blood vessel wall. Extracellular hemoglobin, like that found in HBOCs, has a greater affinity …

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The Effect Of Nacl On Akinete Differentiation In The Cyanobacterium Nostoc Punctiforme, Jonathan Heekin Apr 2008

The Effect Of Nacl On Akinete Differentiation In The Cyanobacterium Nostoc Punctiforme, Jonathan Heekin

Theses and Dissertations

Nostoc punctiforme is a nitrogen-fixing, symbiotic/free-living cyanobacterium. There has been a great deal of research conducted on the genomic nature of N. punctiforme as it pertains to its ecologically important role in the nitrogen cycle in varied environments around the world. My study concentrated on the dormant cell type known as the akinete. Increasing concentrations of NaCl were used to follow the growth phases from germination to akinete formation (lag phase-logarithmic growth phase-stationary phase). I found that increased salt concentrations caused N. punctiforme to form akinetes faster when compared to the control. Germination rates were not greatly increased or shortened …

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Effects Of Hemoglobin-Based Oxygen Carriers On The Vasoactivity Of The Spinotrapezius Muscle Of The Rat, Pete Meliagros Apr 2008

Effects Of Hemoglobin-Based Oxygen Carriers On The Vasoactivity Of The Spinotrapezius Muscle Of The Rat, Pete Meliagros

Theses and Dissertations

Hemoglobin-based oxygen carriers (HBOCs) offer a safe, more plentiful and long term alternate to blood banks. However, they have been found to increase blood pressure which can be attributed to an increase in total peripheral resistance (TPR). Lumenal nitric oxide (NO) scavenging by these HBOCs seems to be responsible for this hypertensive effect. In addition, it is believed that hemoglobin (Hb) tetramers and dimers may extravasate and consume additional nitric oxide in the perivascular and interstitial space. The purpose of the present study was to elucidate the role of NO scavenging and to confirm extravasation as a contributor to HBOC …

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The Ecology Of Fear: Oviposition And Colonization In Aquatic Systems, Leeanna Pletcher Apr 2008

The Ecology Of Fear: Oviposition And Colonization In Aquatic Systems, Leeanna Pletcher

Theses and Dissertations

Amphibians and aquatic invertebrates have complex life histories that link aquatic and terrestrial food webs. It has been suggested that amphibian reproduction is an important source of carbon to some aquatic systems. This process of energy flow may be shaped by shifts in habitat selection in response to predators. We hypothesized that predators decrease colonization and oviposition of prey, reducing active inputs. Thus predation risk is expected to shift the relative amounts of active and passive subsidies. We manipulated the presence of fish predators in aquatic mesocosms. Results suggest hylid treefrog eggs and hydrophilid beetles were less abundant in predator …

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Expression Of Nicotinic Acetylcholine Receptor Mrna As A Function Of Age In Whole Hippocampus Preparations From Wistar Rats, Kasey C. Welch Apr 2008

Expression Of Nicotinic Acetylcholine Receptor Mrna As A Function Of Age In Whole Hippocampus Preparations From Wistar Rats, Kasey C. Welch

Theses and Dissertations

Whole hippocampus preparations, isolated bilaterally, from untreated Wistar rats at various ages (10-90 days old) were analyzed for the mRNA expression of the alpha 2, alpha 3, alpha 4, alpha 5, alpha 7, beta 2, beta 3, and beta 4 neuronal nicotinic acetylcholine receptor subunits. To do so, RNA was isolated from acutely isolated hippocampal samples, converted to cDNA by means of a reverse transcription reaction, then analyzed with quantitative real-time PCR to determine the relative levels of the mRNAs the cells were expressing at the age when the samples were obtained. The relative expression of the levels of RNA …

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Effects Of Predation Risk, Density And Disease On Energy Efficiency In A Larval Anuran, Sarah Crane Apr 2008

Effects Of Predation Risk, Density And Disease On Energy Efficiency In A Larval Anuran, Sarah Crane

Theses and Dissertations

Predation, density and disease affect behavior, morphology and growth. There is a lack of information on how these changes relate to efficiency of energy transfer in anuran larvae, although previous studies suggest that predation should decrease and competition should increase efficiency. Using a 2 x 2 factorial design, we manipulated predation presence and larval density to test how predation risk and density affect energy efficiency. During the experiment, approximately half of the tadpoles were infected by an unknown disease. Neither predation risk nor density affected assimilation or growth efficiency, despite changes in growth and development. Disease, however, decreased gut length …

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Biological Functions Of The Novel Lysophosphatidic Acid (Lpa) Receptor, Lpa4/P2y9/Gpr23, Peilun Lee Apr 2008

Biological Functions Of The Novel Lysophosphatidic Acid (Lpa) Receptor, Lpa4/P2y9/Gpr23, Peilun Lee

Theses and Dissertations

Lysophosphatidic acid (LPA), a naturally occurring phospholipid present in serum and malignant effusions, elicits diverse biological functions through binding and activating specific cell surface G-protein coupled receptors. In addition to the conventional LPA1/Edg2, LPA2/Edg4 and LPA3/Edg7 receptors of the endothelial differentiation gene (Edg) family, LPA4/p2y9/GPR23 of the purinergic receptor family and the related LPA5/GPR92 and LPA6/p2y5 have been identified as novel LPA receptors. These newly identified LPA receptors are structurally distant from the Edg LPA1-3 receptors and couple to Gq, G12/13 and probably Gs subunits. However, the roles of the LPA4-6 receptors in LPA signal transduction and physiology are poorly …

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Children's Perceptions Of The Fitnessgram Fitness Test, Barbara Boone Sampson Mar 2008

Children's Perceptions Of The Fitnessgram Fitness Test, Barbara Boone Sampson

Theses and Dissertations

FITNESSGRAM is a battery of fitness tests that assess if a child's fitness level is, according to a health standard, enough to be considered healthy. These tests include the five components of health-related fitness: aerobic endurance, muscular strength and muscular endurance, flexibility, and body composition. Students are not compared to each other, but to health fitness standards specific to their age and gender that indicate good health. The purpose of this qualitative study was to identify children's perceptions of FITNESSGRAM and determine if self-administration of this fitness test provides a positive experience for the students. Specifically, this study evaluated (a) …

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Physiological Differences Between Land And Water Treadmill Running, Rachel Kemp Rife Mar 2008

Physiological Differences Between Land And Water Treadmill Running, Rachel Kemp Rife

Theses and Dissertations

Objective: To determine if water treadmill running with (WTR-S) or without water shoes (WTR-NS) could produce similar cardiorespiratory responses as land treadmill running (LTR). Design and Setting: A repeated measures design was used to assess the differences between LTR and WTR-S and WTR-NS. All testing was done in either a research laboratory or an athletic training hydro-therapy room. Subjects: Eighteen trained runners (9 men and 9 women) volunteered for this study. All 18 subjects participated in three running conditions. Measurements: Treadmill speed, HR, and SF were assessed at four exercise intensities representing 50%, 60%, 70%, and 80% of land VO2max …

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