Life Sciences Commons^™

Ecology, Phylogenetics, And Conservation Of Draba Asterophora Complex: A Rare, Alpine, Endemic From Lake Tahoe, Usa, Emily Ruth Smith Putnam

Theses and Dissertations

Rare, alpine, endemic species are particularly at risk for extinction. Alpine environments are especially vulnerable to climate change and human impacts, such as ski resort development and snowmaking. Draba asterophora Payson is a rare, alpine species that occurs only in three disjunct mountain-top regions surrounding Lake Tahoe. It is currently threatened by human impacts, such as ski resorts, as well as indirect influences of climate change and therefore in need of better understanding for conservation purposes. Draba asterophora may be able to serve as a case study for other similarly vulnerable, rare, alpine, endemic species with conservation needs. We utilized …

Post-Fire Interactions Between Soil Water Repellency, Islands Of Fertility, And Bromus Tectorum Invasibility, Kaitlynn Jane Fernelius

Theses and Dissertations

An intrinsic link exists between soil moisture and soil nitrogen. Factors that increase or decrease soil moisture can have a profound effect on soil nitrogen cycling, which may have later repercussions in the plant community. Post-fire soil water repellency is one factor that can limit soil moisture acquisition and may indirectly affect nitrogen cycling and weed invasion in woody islands of fertility. Plots centered on burned Juniperus osteosperma trees were either left untreated or treated with a surfactant to ameliorate water repellency. Two years later, soils were excavated from the untreated and treated field plots. In the greenhouse, half of …

Environmental Regulation Of Tidal Wetland Microbial Communities And Associated Biogeochemistry, Ember Morrissey

Theses and Dissertations

Microbial communities play an essential role in carrying out the biogeochemical cycles that sustain life on Earth, yet we know very little about their ecology. One question of particular interest is how environmental conditions shape microbial community structure (i.e., the types of organisms found in the community and their relative abundance), and whether such changes in structure are related to biogeochemical function. It is the aim of this dissertation to address this question via the examination of carbon (C) and nitrogen (N) cycling in wetland ecosystems, which due to their diverse hydrology have a profound influence on biogeochemical cycles. With …

Certain Agave Species Exhibit The Capability To Be Moderately Productive Under Conditions Of High Salt And Drought Stress, Steven J. Bergsten

Theses and Dissertations

Water availability and arable lands are increasingly limiting resources in many parts of the U.S., particularly in semi-arid and arid regions. As a means of addressing food and fuel demands associated with burgeoning population growth, highly productive and water-use efficient crops need to be identified. One potential crop, Agave, merits consideration and evaluation due to its putative capability to provide sustenance and energy despite growing in water-limited regions and on marginal soils. However, little is known regarding the productivity these succulent plants will have under growing conditions of the Southwest, where high concentrated saline soils are abundant, and water is …

Identification Of The Binding Partners For Hspb2 And Cryab Reveals Myofibril And Mitochondrial Protein Interactions And Non-Redundant Roles For Small Heat Shock Proteins, Kelsey Murphey Langston

Theses and Dissertations

Small Heat Shock Proteins (sHSP) are molecular chaperones that play protective roles in cell survival and have been shown to possess chaperone activity. As such, mutations in this family of proteins result in a wide variety of diseases from cancers to cardiomyopathies. The sHSPs Beta-2 (HspB2) and alpha-beta crystalline (CryAB) are two of the ten human sHSPs and are both expressed in cardiac and skeletal muscle cells. A heart that cannot properly recover or defend against stressors such as extreme heat or cold, oxidative/reductive stress, and heavy metal-induced stress will constantly struggle to maintain efficient function. Accordingly, CryAB is required …

Synthesis, Characterization, And Application Of High Surface Area, Mesoporous, Stabilized Anatase Tio2 Catalyst Supports, Rebecca Elizabeth Olsen

Theses and Dissertations

Nanomaterials have attracted substantial attention in the area of catalysis due to the unique properties they exhibit such as high surface areas, intricate pore networks and unique morphologies. TiO2 has attracted attention as a catalyst since the discovery of its high photocatalytic activity by Fuishima and Honda in 1972. Given its high thermal stability, low cost, low environmental impact, and versatility, TiO2 is a widely used commercial catalyst and catalyst support. TiO2 is used in many applications such as photocatalysis is also an excellent support material for noble metals in a number of oxidative synthesis and pollution-control reactions. Though TiO2 …

Discovering Driver Somatic Mutations, Copy Number Alterations And Methylation Changes Using Markov Chain Monte Carlo, Bokhari Yahya

Theses and Dissertations

Nowadays we have tremendous amount of genetic data needing to be interpreted. Somatic mutations, copy number variations and methylation are example of the genetics data we are dealing with. Discovering driver mutations from these combined data types is challenging. Mutations are unpredictable and have broad heterogeneity, which makes our goal hard to accomplish. Many methods have been proposed to solve the mystery of genetics of cancer. In this project we manipulate those above mentioned genetics data types and choose to use and modified an existing method utilizing Markov Chain Monte Carlo (MCMC). The method introduced two properties, coverage and exclusivity. …

Nonlinear Spectroscopic Investigation Of Adsorption To C-18 Model Stationary Phase, Anthony D. Peterson

Theses and Dissertations

Reversed-phase liquid chromatography (RPLC) is a commonly used separation technique in chemistry. Nevertheless, the mechanistic interactions at the molecular level among the eluent, analyte, and the stationary phase are not fully understood. Because of this limited understanding, optimization of the separation must be done experimentally. Learning more about molecular interactions should aid in improving separations. We are currently using second-harmonic generation (SHG) spectroscopy to investigate how analytes adsorb to the surface. SHG is a spectroscopic technique that produces signal only at places of non-isotropic symmetry; this typically occurs at surfaces. SHG can be used to produce surface isotherms of test …

Understory Vegetation Response To Mechanical Mastication Of Piñon And Juniper Woodlands, Jordan Ann Bybee

Theses and Dissertations

Piñon and juniper encroachment and infilling can alter ecosystem processes and decrease resilience and resistance in sagebrush grasslands. Land managers employ a variety of techniques to eliminate these trees and mitigate their negative effects. Mechanical mastication or shredding is an increasingly popular method of removing these trees in Utah. It is a versatile treatment that can reduce canopy fuels, increase infiltration, and reduced sediment loss. We compared vegetation cover for annual and perennial vegetation functional groups on shredded and adjacent unshredded areas across a range of sites. Our approach was to categorize sites by ecological site type (encroachment or tree) …

The Response Of Naive Channel Catfish To Chemical Cues Associated With Predation, Marinda Coulter

Theses and Dissertations

The chemosensory abilities of fishes, are important in order to understand how prey can perceive and avoid predators. Predator-naïve Channel catfish were exposed to four extracts over eight sessions (naïve bass water (NBW), bass that were fed catfish water (BFCW), catfish skin extract (CS), and naïve bass water paired with catfish skin extract (CO)) to determine whether they have an innate predator response to potential chemical cues indicating possible predation risk. Movement was quantified as grid squares crossed, directional changes, and tail beats. Response increased during the first minute following stimulus injection and decreased during the second minute. Channel catfish …

Who's Your Daddy? A Study Of Extra-Pair Copulation And Mating Behaviors Of Protonotaria Citrea, Morton Catherine Heidrich

Theses and Dissertations

Mating behavior has a profound impact on reproductive success and the resulting genetic structure of offspring. Extra-pair copulation is a widely observed behavior within avian species. This study explored the genetic effects of mating behaviors of Prothonotary warblers, Protonotaria citrea (Parulidae), using co-dominant microsatellite markers. Prothonotary warblers are migratory songbirds that build nests in cavities, commonly found in wetland habitats. A set of artificial nest boxes were initiated by Dr Robert Reilly in 2002 in Dutch Gap, Chesterfield County Virginia, USA, a tidal tributary off the James River. From this population, 28 nest boxes were surveyed yielding 47 adults and …

The Acute Effects Of Whole-Body Vibration Training On Passive And Dynamic Flexibility In Gymnasts, Caisa Nicole Brooks

Theses and Dissertations

Gymnasts must attain extreme ranges of flexibility to execute performance requirements, thus effective stretching proves vital to advancement in the sport. This study examined the acute effects of whole-body vibration (WBV) on passive and dynamic flexibility in young, female gymnasts. Participants (n = 27, Junior Olympic levels 5-10) served as their own control. Measurements of passive and dynamic flexibility were obtained using the TOPS forward split testing method to examine passive flexibility and dynamic flexibility was measured via split jumps that were analyzed with video and Dartfish software. According to randomized order, all participants completed a stretching protocol either with …

Pharmacokinetics Of Dexamethasone Delivered Via Iontophoresis, Justin Holbrook Rigby

Theses and Dissertations

Study Design: Controlled laboratory study. Objectives: To determine the time course of dexamethasone sodium phosphate (Dex-P) iontophoresis delivery to underlying tissues using microdialysis. Background: The efficacy of iontophoresis at delivering Dex-P through the skin is unknown in humans because of the lack of minimally invasive measurement techniques. Methods: Sixty-four healthy male participants (age = 24.4 ± 3.3 yrs, height = 71.8 ± 2.5 in, weight = 181.8 ± 26.1 lbs) were randomly assigned into one of six groups: 1) 1 mA current, 1 mm probes depth ; 2) 1 mA current, 4 mm probes depth; 3) 2 mA current, 1 …

Metabolic Remodeling And Mitochondrial Dysfunction In Maladaptive Right Ventricular Hypertrophy Secondary To Pulmonary Arterial Hypertension, Jose Gomez-Arroyo

Theses and Dissertations

Right ventricular dysfunction is the most frequent cause of death in patients with pulmonary arterial hypertension. Although abnormal energy substrate use has been implicated in the development of chronic left heart failure, data describing such metabolic remodeling in failing right ventricular tissue remain incomplete. In the present dissertation we sought to characterize metabolic gene expression changes and mitochondrial dysfunction in functional and dysfunctional RV hypertrophy. Two different rat models of RV hypertrophy were studied. The model of right ventricular failure (SU5416/hypoxia) exhibited a significantly decreased gene expression of peroxisome proliferator-activated receptor- coactivator-1α, peroxisome proliferator- activated receptor-α and estrogen-related receptor-α. The …

Regulation Of Satiety Quiescence: Cyclic Gmp, Tgf Beta, And The Asi Neuron, Thomas Gallagher

Theses and Dissertations

The worm Caenorhabditis elegans is a well-studied model organism in numerous aspects of its biology. This small free living nematode has less than 1,000 cells, but shows clear conservation in both signaling and behavior to mammals in aspects of appetite control. This is of importance to humans, where failure of appetite control is a major factor in the unprecedented obesity epidemic that we see today. In general, worm behavior reflects its internal nutritional state and the availability and quality of food. Specifically, worms show a behavioral state that mimics aspects of the mammalian behavioral satiety sequence, which has been termed …

Formation And Analysis Of Zinc Oxide Nanoparticles And Zinc Oxide Hexagonal Prisms And Optical Analysis Of Cadmium Selenide Nanoparticles, Jared M. Hancock

Theses and Dissertations

In this dissertation, methods to synthesize ZnO are reported. First, zinc oxide nanoparticles were synthesized with small amounts of transition metal ions to create materials called dilute magnetic semiconductors (DMS). We employed a low temperature sol-gel method that produces ZnO nanoparticles of reproducible size and incorporates cobalt, nickel, and manganese ions into the nanoparticles. Conditions were controlled such that a range of amounts of Co, Ni, and Mn were incorporated. The incorporation was tracked by color changes in the white ZnO powder to blue for Co, green for Ni and yellow for Mn. XRD measurements showed the nanoparticles were on …

Structure And Function Of Proteins Investigated By Crystallographic And Spectroscopic Time-Resolved Methods, Namrta Purwar

Theses and Dissertations

Biomolecules play an essential role in performing the necessary functions for life. The goal of this thesis is to contribute to an understanding of how biological systems work on the molecular level. We used two biological systems, beef liver catalase (BLC) and photoactive yellow protein (PYP). BLC is a metalloprotein that protects living cells from the harmful effects of reactive oxygen species by converting H2O2 into water and oxygen. By binding nitric oxide (NO) to the catalase, a complex was generated that mimics the Cat-H2O2 adduct, a crucial intermediate in the reaction promoted by the catalase. The Cat-NO complex is …

Transcending Microbial Source Tracking Techniques Across Geographic Borders: An Examination Of Human And Animal Microbiomes And The Integration Of Molecular Approaches In Pathogen Surveillance In Brazil And The United States, Amber Mae Koskey

Theses and Dissertations

Waterborne illnesses, attributed to the ingestion or contact with contaminated water, present a significant global health concern. Surface water sources can be impacted by wide array of pollution inputs, but fecal pollution generates the most significant and acute threat to human health. Therefore, the detection of fecal bacteria in surface water sources remains an important public health objective. Current surface water monitoring employs the use of fecal indicator bacteria (FIB) including E. coli and enterococci as proxies for pathogenic organisms carried in fecal pollution. These traditional indicators, detected by culture-based microbiological methods, do not discriminate fecal sources from another. New …

Neural Responses During Trace Conditioning With Face And Non-Face Stimuli Recorded With Magnetoencephalography, Nicholas Lee Balderston

Theses and Dissertations

During fear conditioning a subject is presented with an initially innocuous stimulus like an image (conditioned stimulus; CS) that predicts an aversive outcome like a mild electric shock (unconditioned stimulus; UCS). Subjects rapidly learn that the CS predicts the UCS, and show autonomic fear responses (CRs) during the presentation of the CS. When the CS and the UCS coterminate, as is the case for delay conditioning, individuals can acquire CRs even if they are unable to predict the occurrence of the UCS. However when there is a temporal gap between the CS and the UCS, CR expression is typically dependent …

Lake Michigan Hydrodynamics: Mysis And Larval Fish Interactions, Yutta Wang

Theses and Dissertations

I studied the interactions between Lake Michigan hydrodynamics (the spring thermal bar) and Mysis, deepwater sculpin, and burbot larvae. The thermal bar is a zone of sinking 4º С water that separates warmer inshore water from colder offshore water. Mysis was a major bycatch of sampling for larval fishes. The density of Mysis did not differ statistically between inshore (about 6º С) and offshore of the thermal bar, but the percentage of Mysis that were newborns was significantly higher inshore (P = 0.007). These "early start" coastal Mysis may have an advantage in growth and survival, but with the risk …

The Role Of The Amygdala, Retrosplenial Cortex, And Medial Prefrontal Cortex In Trace Fear Extinction And Reconsolidation, Janine Lynn Kwapis

Theses and Dissertations

A wealth of research has outlined the neural circuits responsible for the consolidation, reconsolidation, and extinction of standard "delay" fear conditioning, in which awareness is not required for learning. Far less is understood about the neural circuit supporting more complex, explicit associations. "Trace" fear conditioning is considered to be a rodent model of explicit fear because it relies on the cortex and hippocampus and requires explicit contingency awareness in humans for successful acquisition. In the current set of studies, we aimed to better characterize the neural circuit supporting the consolidation, reconsolidation, and extinction of trace fear in order to better …

Evaluation Of Vdr-Coactivator Inhibitors Using Biochemical And Cell-Based Assays, Athena Marie Baranowski

Theses and Dissertations

ABSTRACT

EVALUATION OF VDR–COACTIVATOR INHIBITORS USING BIOCHEMICAL AND CELL–BASED ASSAYS

by

Athena Baranowski

The University of Wisconsin–Milwaukee, 2013

Under the Supervision of Dr. Alexander Arnold

The vitamin D receptor (VDR) is a ligand–dependent transcription factor, which belongs to the nuclear receptor superfamily. VDR–mediated gene regulation is governed by coregulators (coactivators and corepressors). VDR coregulator binding inhibitors (CBIs), which were discovered using high throughput screening (HTS), were evaluated using cell–based assays and biochemical assays to determine their ability to inhibit the interaction between VDR and steroid receptor coactivator–2 (SRC–2). Determining their ability to inhibit the VDR–SRC–2 interaction can lead to the …

Arabidopsis Serk1 And 2 Regulate Anther Development As Co-Receptors Of Ems1, Yao Wang

Theses and Dissertations

In flowering plants, male reproductive cell differentiation, one of the most critical events in the early stage of sexual reproduction, occurs during anther development. In the model plant species Arabidopsis, anther development in each lobe results in the differentiation of five highly organized cell layers with unique identities, including the central male reproductive cells and four somatic cell layers. These features make the Arabidopsis anther an ideal system in which to investigate the mechanisms of cell fate determination and differentiation. Previous studies have demonstrated that a leucine-rich repeat receptor-like kinase (LRR-RLK), EXCESS MICROSPOROCYTES1 (EMS1/EXS1), plays an important role during Arabidopsis …

Phylogeographic Inference Of Insular Mule Deer (Odocoileus Hemionus) Divergence In North America's Desert Southwest, Ona Alminas

Theses and Dissertations

Though mule deer (Odocoileus hemionus) persist in robust populations throughout most of their North American distribution, nearly 60% of their historic range in México has declined due to habitat loss and unregulated hunting. Two of the six subspecies inhabiting México's deserts and Baja California peninsula are of conservation concern, occurring on land bridge islands in the Pacific Ocean (O. h. cerrosensis on Cedros Island: threatened) and in the Sea of Cortés (O. h. sheldoni on Tiburón Island: endangered). Focusing on the desert southwest (n=449 deer), we obtained 1,611 bp of mtDNA sequence (control region: 583 bp; cytochrome b gene: 1,028 …

Influence Of Genetic Variation In The Biotic Environment On Phenotypic Variation In A Plant-Feeding Insect, Darren Rebar

Theses and Dissertations

While many species spend much of their lives in close association with other organisms, only recently have biologists started to explore the implications of the biotic nature of environments for their role as causes of variation in phenotypes. This means that the genotypes of individuals that constitute the biotic environment may influence the phenotypes of individuals that live in that environment. These are called indirect genetic effects (IGEs) when they occur between conspecifics, and interspecific indirect genetic effects (IIGEs) when they occur between heterospecifics. However, the impact of genetic variation in biotic environments remains largely unknown. I used a member …

Evaluating The Influence Of Environmental Factors On The Rate Of Extra-Pair Matings In Tropical And Temperate Populations Of The House Wren (Troglodytes Aedon), Kaitlin Claire Mckenney

Theses and Dissertations

Considerable variation exists in the rate of extra-pair matings (EPMs) in birds. Environmental variability likely influences EPM rates within species, but the effects of local environmental factors on EPM rates are largely unpredictable. To determine whether broad-scale environmental factors might be better predictors of EPM rates within species, we quantified levels of extra-pair paternity in the house wren (Troglodytes aedon) in four populations spanning a range of latitude, elevation, and primary productivity (measured by actual evapotranspiration rates). Our results indicated an intermediate and variable level of EPM among populations (6 -31% extra-pair young) that was not significantly affected by 3 …

Protein Association In Living Cells Using Fret Spectrometry: Application To G-Protein Coupled Receptors, Suparna Patowary

Theses and Dissertations

Recent advancements in fluorescence microscopy coupled with newly developed fluorescent tags have transformed Fluorescence (Förster) Resonance Energy Transfer (FRET) into a powerful tool studying in vivo molecular interactions with improved spatial (angstrom) resolution. Though widely used to study protein-protein interactions, generalizing and testing the FRET theory for oligomeric complexes containing multiple donors and acceptors has only become possible in recent years. Therefore, many aspects of it are yet unexplored.

In this work, we tested the kinetic theory of FRET using linked fluorescent proteins located in the cytoplasm or at the plasma membrane. We used a novel method developed in our …

Life After Adhesion: L-Selectin Throughout The T Cell Lifespan, Abner Garcia Fernandez

Theses and Dissertations

Lymphocytes require antigenic encounter to activate and proliferate, eventually clearing the source of antigenic challenge. The peripheral lymph nodes (PLN) are the primary sites of antigenic encounter and thus the ability of lymphocytes to migrate to this tissue is a requirement for mounting effective immune responses. The process of lymphocyte migration to the PLN is known as the "adhesion cascade". Specifically, lymphocytes are captured from the blood through the adhesion molecule, L-selectin, followed by CC chemokine receptor 7 (CCR7)-mediated integrin activation, which ultimately results in cell transmigration into the PLN. Because the PLN is the site where antigenic encounter is …

The Role Of Gap-43 Phosphorylation In Axon Behavior In The Developing Zebrafish Visual System, Jennifer Forecki

Theses and Dissertations

Developing neurons extend processes to specific targets and establish connections that are essential for future function of the nervous system. One of these processes, the axon, has a motile tip called a growth cone that rearranges its membrane-associated actin cytoskeleton to turn toward or away from environmental guidance cues. Growth associated protein 43 (GAP-43) is one of the most abundant proteins associated with axonal growth cone membranes and is known to modulate the formation and stability of the actin cytoskeleton during axon guidance. Protein kinase C (PKC)-mediated phosphorylation of GAP-43 on serine 42 regulates its interactions with actin. Phosphorylated GAP-43 …

A Synthetic Biology Approach To Engineering New Anticancer Agents, Shane Robert Wesener

Theses and Dissertations

Histone deacetylase (HDAC) inhibitors are becoming increasingly valuable therapeutic agents in treatment of several types of malignancies. FK228 is a depsipeptde anticancer compound produced by Chromobacterium violaceum no. 968 through a nonribosomal peptide synthetase (NRPS)-polyketide synthase (PKS) hybrid assembly line. In the present study, reconstitution of the biosynthetic pathway responsible for the production of FK228 revealed cross-talk between modular PKS and fatty acid synthase. This pathway contains two PKS modules on the DepBC enzymes that lack a functional acyltransferase (AT) domain, and no apparent AT-encoding gene exists within the gene cluster or its vicinity. We reported through heterologous expression of …