Life Sciences Commons^™

The Role Of Mate Preference And Personality On Reproductive Performance In An Ex-Situ Conservation Breeding Program For The Giant Panda (Ailuropoda Melanoleuca), Meghan S. Martin

Dissertations and Theses

Successful captive-breeding and re-introduction programs must have the ability to breed a surplus of genetically suitable animals for release into the wild. Unfortunately, many individuals in captive breeding programs often do not reproduce even when they are apparently healthy and presented with genetically appropriate mates. Mate choice can affect multiple parameters of reproductive sperformance, including mating success, offspring production, survival, and fecundity. We investigated the role of mate preference and personality on the reproductive performance of male and female giant pandas (Ailuropoda melanoleuca) as measured by intromission success and litter production. We conducted these studies on giant pandas at the …

Cascades Island Lamprey Passage Structure: Evaluating Passage And Migration Following Structure Modifications, Siena Marie Lopez-Johnston

Dissertations and Theses

Pacific lamprey (Entosphenus tridentatus), an endemic species to the Columbia River Basin, U.S.A, has experienced staggering decreases in returns to spawning territories in recent decades. As lamprey are threatened severely by a lack of passage at mainstem dams, lamprey specific passage structures have been designed and constructed to address the problem. The Cascades Island Lamprey Passage Structure (LPS) at Bonneville Dam is the longest and steepest structure of its type, following the addition of an exit pipe which allows lampreys to travel from the tailrace of the dam to the forebay. The intent of this study was to …

Agricultural Classification Of Multi-Temporal Modis Imagery In Northwest Argentina Using Kansas Crop Phenologies, Jarrett Alexander Keifer

Dissertations and Theses

Subtropical deforestation in Latin America is thought to be driven by demand for agricultural land, particularly to grow soybeans. However, existing remote sensing methods that can differentiate crop types to verify this hypothesis require high spatial or spectral resolution data, or extensive ground truth information to develop training sites, none of which are freely available for much of the world. I developed a new method of crop classification based on the phenological signatures of crops extracted from multi-temporal MODIS vegetation indices. I tested and refined this method using the USDA Cropland Data Layer from Kansas, USA as a reference. I …

Assessment Of Arbuscular Mycorrhizal Symbiosis On Invasion Success In Brachypodium Sylvaticum, Caitlin Elyse Lee

Dissertations and Theses

The effects that mutualistic soil biota have on invasive species success is a growing topic of inquiry. Studies of the interactions between invasive plants and arbuscular mycorrhizal fungi (AMF) have shown changes in AMF community composition, reductions in AMF associations in invasive plants, and changes in native species fitness and competitive outcomes in invasive-shifted AMF communities. These findings support the degraded mutualist hypothesis, where invasive species alter the mutualist community composition, resulting in detrimental associations with the new mutualist community for native species. Here I present two studies that examine various aspects of the arbuscular mycorrhizal fungal (AMF) mutualism in …

Nuwuvi (Southern Paiute) Ecological Knowledge Of Piñon-Juniper Woodlands: Implications For Conservation And Sustainable Resource Use In Two Southern Nevada Protected Areas, Brian John Lefler

Dissertations and Theses

Nuwuvi (Southern Paiute) have inhabited the southern Great Basin for thousands of years, and consider Nuvagantu (where snow sits) in the Spring Mountains landscape to be the locus of their creation as a people. Their ancestral territory spans parts of Nevada, Utah, Arizona, and California. My research identifies and describes the heterogeneous character of Nuwuvi ecological knowledge (NEK) of piñon-juniper woodland ecosystems within two federal protected areas (PAs) in southeastern Nevada, the Spring Mountains National Recreation Area (SMNRA) and the Desert National Wildlife Refuge (DNWR), as remembered and practiced to varying degrees by 22 select Nuwuvi knowledge holders. I focus …

Characterization Of Functional Domains Of Cul3, An E3 Ubiquitin Ligase, Using Chimeric Analysis, Jennifer Anne Mitchell

Dissertations and Theses

Modification of cellular proteins with molecules of ubiquitin is an important process that regulates the activity of cellular proteins. Cullin RING ligases (CRLs) are multi-subunit complexes that act in concert with E2 enzymes to attach molecules of ubiquitin to protein substrates. There are seven CRLs in mammalian cells (Cul1, Cul2, Cul3, Cul4A, Cul4B, Cul5, and Cul7) that are highly homologous in sequence and structure. CRLs possess a highly conserved C- terminal domain that interacts with E2 enzymes, and a more variable N- terminal domain which recruits substrates through distinct substrate adapter molecules. Despite the structural similarity, these CRLs recognize distinct …

The Effect Of Docosahexaenoic Acid (Dha)-Containing Phosphatidylcholine (Pc) On Liquid-Ordered And Liquid-Disordered Coexistence, Yongwen Gu

Dissertations and Theses

Plasma membranes are essential to both the structure and function of mammalian cells. The first unifying paradigm of membrane structure, the Fluid Mosaic Model, is no longer considered adequate to describe the many non-homogeneous lipid structures that have been observed in both natural and model membranes over the past approximately thirty years. The field of membrane biophysics now appreciates that the complex mixture of different lipid species found in natural membranes produces a range of dynamic, laterally segregated, non-homogeneous structures which exist on time scales ranging from microseconds to minutes.

When sphingomyelin (SM), POPC and cholesterol are all present in …

Testing The Ecological And Physiological Factors Influencing Reproductive Success In Mosses, Erin Elizabeth Shortlidge

Dissertations and Theses

As non-vascular, early land plants with an aquatic ancestry, mosses do not regulate internal water conditions separate from that of their environment and as a result, evolved mechanisms to survive in a terrestrial world out of water. Yet, there is a widely accepted dogma that moss reproductive success is solely dependent on rainfall events carrying swimming, bi-flagellate sperm across the landscape to reproductively mature and receptive female mosses--but this classic view of moss reproduction may be too simplistic. In this dissertation I test the assumptions of reproductive limitation in mosses and present novel findings in a basal, yet understudied terrestrial …

Calcium Transport Inhibition, Stimulation, And Light Dependent Modulation Of The Skeletal Calcium Release Channel (Ryr1) By The Prototropic Forms Of Pelargonidin, Thomas Joseph Dornan

Dissertations and Theses

The principle calcium regulator in the muscle cell is the calcium ion release channel (RyR). Improper calcium homeostasis in the muscle cell is the foundation of many pathological states and has been targeted as a contributing factor to ventricular tachycardia, which is known to precede sudden cardiac arrest.

Numerous endogenous and exogenous compounds can affect the way RyR regulates calcium. In this study the anthocyanidin Pelargonidin (Pg), an important natural colorant and dietary antioxidant, is evaluated for its effect on regulating the transport of calcium through the RyR1 of skeletal muscle sarcoplasmic reticulum. Pelargonidin undergoes time dependent structural changes in …

The Orientation Of The Pyrococcus Furiosus Transcription Factor Tfb2 In The Transcription Initiation Complex, Arati Bhattarai

Dissertations and Theses

The hyperthermophile archaeon, Pyrococcus furiosus encodes two eukaryotic TFIIB family proteins, TFB1 and TFB2. TFB1 is very similar to TFIIB in terms of sequence homology and function, whereas TFB2 is unusual as it is missing highly conserved sequences in its N-terminal domain that are present in TFIIB and TFB1. Despite this, TFB2 is effective in transcription process, albeit with lower efficiency compared to TFB1. Other archaea also contain multiple TFBs, but unlike Pyrococcus furiosus TFB2, these multiple TFBs have higher sequence homology to each other and have similar transcription efficiencies. Photochemical cross-linking experiments have shown that the B-reader of TFB …

Behavioral Observation And Paternal Investment Of Eastern Kingbirds At Malheur National Wildlife Refuge, Christopher Michael Chutter

Dissertations and Theses

We have been studying the population of Eastern Kingbirds breeding in riparian habitats in Malheur National Wildlife Refuge (eastern Oregon) since 2002. These efforts have created an ideal research environment wherein most adults in the population have been color banded and DNA sampled and, as part of other research projects, nearly all broods since 2003 have been paternity tested. I decided to use behavioral video recordings of parental nest behavior undertaken between 2003 and 2010 for two unrelated projects. First, I tested the effectiveness of video sampling nesting behavior (see below and chapter 2). Second, I tested whether male kingbirds …

Seasonal And Sex Differences In The Effects Of Melatonin On Brain Arginine Vasotocin In Green Treefrogs (Hyla Cinerea): Relationship To Melatonin Receptor 1a, Christina Marie Howard

Dissertations and Theses

Critical life history events such as breeding, migration and hibernation must take place in the correct environmental context to minimize deleterious consequences on survival and reproductive fitness. Neuroendocrine mechanisms synchronizing internal physiological states with extrinsic environmental cues are vital to timing life history events appropriately. Secretion of the pineal hormone melatonin is sensitive to light and temperature cues, which provides a physiological indicator of time of day and time of year for organisms. Melatonin influences seasonal reproduction in a variety of vertebrates, likely by altering the synthesis and/or release of reproductive neuropeptides in the brain. The neuropeptides arginine vasotocin and …

Informal Trails And The Spread Of Invasive Species In Urban Natural Areas: Spatial Analysis Of Informal Trails And Their Effects On Understory Plant Communities In Forest Park, Portland, Oregon, Jill Elise Van Winkle

Dissertations and Theses

The risk of spread and establishment of invasive species to interior habitat within urban parks is of great concern to park managers and ecologists. Informal trails as a vector for this transmission are not well understood. To characterize effects of informal trails on understory plant communities, I conducted a study of the informal trail network in Forest Park, Portland, Oregon. The system of 382 informal trails was mapped and evaluated qualitatively, and from this population a systematic sample was selected for analysis. To identify hotspots of informal trail activity, showing the relationship of informal trails to formal trails, other park …

Temperature Dependent Transcription Initiation In Archaea: Interplay Between Transcription Factor B And Promoter Sequence, Ming-Hsiao Wu

Dissertations and Theses

In Pyrococcus furiosus (Pfu), a hyperthermophile archaeon, two transcription factor Bs, TFB1 and TFB2 are encoded in the genomic DNA. TFB1 is the primary TFB in Pfu, and is homologous to transcription factor IIB (TFIIB) in eukaryotes. TFB2 is proposed to be a secondary TFB that is compared to TFB1, TFB2 lacks the conserved B-finger / B-reader / B-linker regions which assist RNA polymerase in transcription start site selection and promoter opening functions respectively. P. furiosus, like all Archaea, encodes a single transcription factor E (TFE), that is homologous to the N-terminus of transcription factor II …

Health And Well-Being Of Young Adults With Cerebral Palsy, Susan Elizabeth Sienko

Dissertations and Theses

Health is a multidimensional, holistic, concept integrating physical and mental health. In childhood, the most common cause of physical disability is Cerebral Palsy (CP). For individuals with CP, health and well-being is impacted by the complex interactions among their physical impairments, activity, participation and environmental barriers. Although CP is considered non-progressive, secondary conditions (pain and fatigue) and their functional consequences have been found to worsen as the individual with CP ages. While preliminary evidence shows that many of the physical impairments (pain, fatigue, depression) reported in adults with CP begin during late adolescence, there is little information about the role …

Mitochondrial Reactive Oxygen Species (Ros): Which Ros Is Responsible For Cardioprotective Signaling?, Anders Olav Garlid

Dissertations and Theses

Mitochondria are the major effectors of cardioprotection by procedures that open the mitochondrial ATP-sensitive potassium channel (mitoK_ATP), including ischemic and pharmacological preconditioning. MitoK_ATP opening leads to increased reactive oxygen species (ROS), which then activate a mitoK_ATP-associated PKCε, which phosphorylates mitoK_ATP and leaves it in a persistent open state (Costa, ADT and Garlid, KD. Am J Physiol 295, H874-82, 2008). Superoxide (O₂^•-), hydrogen peroxide (H₂O₂), and hydroxyl radical (HO^•) have each been proposed as the signaling ROS but the identity of the ROS responsible for this …

Agricultural Management Decisions Impact Isoprene Emission And Physiology Of Arundo Donax, An Emerging Bioenergy Crop, Jason Charles Maxfield

Dissertations and Theses

Arundo donax (Giant Reed) is quickly being developed as a rapidly-growing, robust, and highly productive bioenergy crop, with large scale cultivation of this species planned for the Columbia River basin of the Pacific Northwest (USA). Despite its potential as a next generation biomass crop, relatively few studies have examined the physiological performance of A. donax under agricultural conditions. Unlike traditional crops, A. donax is known to be a high-emitter of the volatile compound isoprene, which may significantly impact regional air quality, but it has not been widely cultivated in North America and little is known about how this species will …

Investigating A Role For The Ccaat/Enhancer-Binding Protein Δ In The Developing Zebrafish, Alisha Jennifer Beirl

Dissertations and Theses

The CCAAT/enhancer-binding protein delta (C/EBPδ) is a highly conserved transcription factor capable of regulating numerous cell fate processes, such as cell growth, differentiation, proliferation and apoptosis. C/EBPδ is inducible during cellular stress responses, including inflammation and responses to growth factor deprivation or thermal stress. C/EBPδ is stress-inducible in a diversity of fishes, including the zebrafish Danio rerio; however, little is known about its role in fish development. Here I show that overexpression of C/EBPδ leads to severe developmental defects, including reduced body length, edema, liver malformation and retinal abnormalities. The proportion of individuals that display developmental abnormalities is significantly …

Effects Of Arbuscular Mycorrhizal Fungal Infection And Common Mycelial Network Formation On Invasive Plant Competition, Rachael Elizabeth Workman

Dissertations and Theses

Understanding the biotic factors influencing invasive plant performance is essential for managing invaded land and preventing further exotic establishment and spread. I studied how competition between both conspecifics and native co-habitants and arbuscular mycorrhizal fungal (AMF) impacted the success of the invasive bunchgrass Brachypodium sylvaticumin early growth stages. I examined whether invasive plants performed and competed differently when grown in soil containing AMF from adjacent invaded and noninvaded ranges in order to determine the contribution of AMF to both monoculture stability and spread of the invasive to noninvaded territory. I also directly manipulated common mycelial network (CMN) formation by AMF …

The Boiling Springs Lake Metavirome: Charting The Viral Sequence-Space Of An Extreme Environment Microbial Ecosystem, Geoffrey Scott Diemer

Dissertations and Theses

Viruses are the most abundant organisms on Earth, yet their collective evolutionary history, biodiversity and functional capacity is not well understood. Viral metagenomics offers a potential means of establishing a more comprehensive view of virus diversity and evolution, as vast amounts of new sequence data becomes available for comparative analysis.
Metagenomic DNA from virus-sized particles (smaller than 0.2 microns in diameter) was isolated from approximately 20 liters of sediment obtained from Boiling Springs Lake (BSL) and sequenced. BSL is a large, acidic hot-spring (with a pH of 2.2, and temperatures ranging from 50°C to 96°C) located in Lassen Volcanic National …

Abundance And Distribution Of Major And Understudied Archaeal Lineages At Globally Distributed Deep-Sea Hydrothermal Vents, Alexander Fenner Rutherford

Dissertations and Theses

Deep-sea hydrothermal vents are some of the most biologically productive ecosystems on Earth, yet receive little to no input of photosynthetically derived organic matter. The trophic system at hydrothermal vents is based primarily on the reduction-oxidation (redox) of inorganic chemicals by Bacteria and Archaea. However, the distributional patterns of the microorganisms that colonize deep-sea hydrothermal vent deposits and their link to the geologic setting are still not deeply understood.

The goal of the studies presented in this thesis was to quantify the abundance, and distribution of major and understudied vent colonizing archaeal groups from globally distributed and geochemically distinct hydrothermal …

Managing For Resistance And Resilience Of Northern Great Lakes Forests To The Effects Of Climate Change, Matthew Joshua Duveneck

Dissertations and Theses

Climate change is expected to drastically change the environmental conditions which forests depend. Lags in tree species movements will likely be outpaced by a more rapidly changing climate. This may result in species extirpation, a change in forest structure, and a decline in resistance and resilience (i.e., the ability to persist and recover from external perturbations, respectively). In the northern Great Lakes region of North America, an ecotone exists along the boreal-temperate transition zone where large changes in species composition exist across a climate gradient. Increasing temperatures are observed in the more southern landscapes. As climate change is expected to …

Chytrid Loads, Pathogen Prevalence, And Contemporary Host Source-Sink Dynamics In Dry Vs. Wet Forests; Evaluating Refugia From Disease In Australian Torrent Frogs., Barbara Rizzo

Dissertations and Theses

No abstract provided.

The Impact Of Saccadic Eye Movement Training On Saccade Accuracy And Latency, Stephanie Montenegro

Dissertations and Theses

No abstract provided.

Kos Modulation Of Mitochondrial Fission And Fusion, Herman Kucharavy

Dissertations and Theses

No abstract provided.

Structure-Function Analysis Of Zapc, An Ftsz-Ring Stabilizer, In Escherichia Coli Cytokinesis, Lukasz Tchorzewski

Dissertations and Theses

In Escherichia coli, cell division is defined by the polymerization and constriction of a cytokinetic ring (Z ring) formed by FtsZ, a tubulin-like GTPase, at midcell. Division also involves the formation of a multi-protein complex at midcell known as the divisome. Several divisome proteins promote the assembly/disassembly processes of FtsZ, thereby exercising spatiotemporal control over division. Among FtsZ regulatory proteins are the FtsZ ringassociated proteins (Zap), which either directly or indirectly stabilize the Z-ring by increasing lateral interactions amongst FtsZ protofilaments in the Z-ring. ZapA-D are recruited during early cytokinesis and have overlapping functions in stabilizing FtsZ at midcell, but …

Investigating Innate Immune Signaling Cross-Talk In A Drosophila Tumor-Inflammation Model, Rebecca Moore

Dissertations and Theses

No abstract provided.

Methodological Advancements For Improving Performance And Generating Ensemble Ecological Niche Models, Robert Boria

Dissertations and Theses

This study employs spatial filtering of occurrence data with the aim of reducing overfitting to sampling bias in ecological niche models (ENMs). Sampling bias in geographic space leads to localities that may also be biased in environmental space. If so, the model can overfit to those biases. As a preliminary test addressing this issue, we used Maxent, bioclimatic variables, and occurrence localities of a broadly distributed Malagasy tenrec, Microgale cowani (Family Tenrecidae: Subfamily Oryzorictinae). We modeled the abiotically suitable area of this species using three distinct datasets: unfiltered, spatially filtered, and rarefied unfiltered localities. To quantify overfitting and model performance, …

Screen For Suppressors And Enhancers Of Excitotoxic Neurodegeneration, Anthony Omorodion Edokpolo

Dissertations and Theses

Excitotoxicity is an important and frequently observed neurodegenerative process. Excitotoxicity mediates brain damage in a range of diseases and conditions including stroke, and is triggered by excessive stimulation of glutamatergic synapses. In spite of extensive studies, the molecular mechanisms involved in excitotoxicity following the over-activation of postsynaptic glutamate receptors are not well understood, and clinical trials based on our partial understanding of the process ended with disappointment. Genetic screens in simple animal models offer a powerful alternative approach, since screens are unbiased, analysis is facilitated by strong research tools, and cellular mechanisms are highly conserved through evolution. We produced a …

Caffeine's Attenuation Of Cocaine-Induced Deficiency In Acoustic Startle Response By Inhibition Of Adenosine In A Sex And Dose Dependent Manner, Lauren B. Malave

Dissertations and Theses

No abstract provided.