Life Sciences Commons^™

Mechanism Of Rapid Electron Transfer Reactions Involving Cytochrome Bc1, Cytochrome C And Cytochrome Oxidase, Jeremy Erik Durchman

Graduate Theses and Dissertations

Electron transfer between mitochondrial proteins complexes represents the primary means by which living things acquire the requisite energy for survival. The coupling of electron transfer to proton translocation creates an electrochemical gradient that drives the synthesis of highly energetic compounds such as ATP. The purpose of these studies is to measure rates of electron transfer and elucidate the important governing factors in the redox events involving cytochrome bc1, cytochrome c and cytochrome oxidase. Using rapid initiation of redox events triggered by laser flash excitation of ruthenium compounds, and strategically monitoring unique spectral properties of these proteins in the visible region …

Chromosome-End Knockoff Strategy To Reshape Alkaloid Profiles Of A Fungal Endophyte, Simona Florea, Timothy D. Phillips, Daniel G. Panaccione, Mark L. Farman, Christopher L. Schardl

Plant Pathology Faculty Publications

Molecular genetic techniques to precisely eliminate genes in asexual filamentous fungi require the introduction of a marker gene into the target genome. We developed a novel strategy to eliminate genes or gene clusters located in subterminal regions of chromosomes, and then eliminate the marker gene and vector backbone used in the transformation procedure. Because many toxin gene clusters are subterminal, this method is particularly suited to generating nontoxic fungal strains. We tested this technique on Epichloë coenophiala, a seed-transmissible symbiotic fungus (endophyte) of the important forage grass, tall fescue (Lolium arundinaceum). The endophyte is necessary for maximal …

Identification Of Diverse Mycoviruses Through Metatranscriptomics Characterization Of The Viromes Of Five Major Fungal Plant Pathogens, Shin-Yi Lee Marzano, Berlin D. Nelson, Olutoyosi Ajayi-Oyetunde, Carl A. Bradley, Teresa J. Hughes, Glen L. Hartman, Darin M. Eastburn, Leslie L. Domier

Plant Pathology Faculty Publications

Mycoviruses can have a marked effect on natural fungal communities and influence plant health and productivity. However, a comprehensive picture of mycoviral diversity is still lacking. To characterize the viromes of five widely dispersed plant-pathogenic fungi, Colletotrichum truncatum, Macrophomina phaseolina, Diaporthe longicolla, Rhizoctonia solani, and Sclerotinia sclerotiorum, a high-throughput sequencing-based metatranscriptomic approach was used to detect viral sequences. Total RNA and double-stranded RNA (dsRNA) from mycelia and RNA from samples enriched for virus particles were sequenced. Sequence data were assembled de novo, and contigs with predicted amino acid sequence similarities to viruses in the …

Simultaneous Quantitation Of Oxidized And Reduced Glutathione Via Lc-Ms/Ms: An Insight Into The Redox State Of Hematopoietic Stem Cells, Dustin W. Carroll, Diana Howard, Haining Zhu, Christian M. Paumi, Mary Vore, Subbarao Bondada, Ying Liang, Chi Wang, Daret K. St. Clair

Toxicology and Cancer Biology Faculty Publications

Cellular redox balance plays a significant role in the regulation of hematopoietic stem-progenitor cell (HSC/MPP) self-renewal and differentiation. Unregulated changes in cellular redox homeostasis are associated with the onset of most hematological disorders. However, accurate measurement of the redox state in stem cells is difficult because of the scarcity of HSC/MPPs. Glutathione (GSH) constitutes the most abundant pool of cellular antioxidants. Thus, GSH metabolism may play a critical role in hematological disease onset and progression. A major limitation to studying GSH metabolism in HSC/MPPs has been the inability to measure quantitatively GSH concentrations in small numbers of HSC/MPPs. Current methods …

Cellular And Subcellular Oxidative Stress Parameters Following Severe Spinal Cord Injury, Nishant P. Visavadiya, Samir P. Patel, Jenna L. Vanrooyen, Patrick G. Sullivan, Alexander G. Rabchevsky

Spinal Cord and Brain Injury Research Center Faculty Publications

The present study undertook a comprehensive assessment of the acute biochemical oxidative stress parameters in both cellular and, notably, mitochondrial isolates following severe upper lumbar contusion spinal cord injury (SCI) in adult female Sprague Dawley rats. At 24 h post-injury, spinal cord tissue homogenate and mitochondrial fractions were isolated concurrently and assessed for glutathione (GSH) content and production of nitric oxide (NO^•), in addition to the presence of oxidative stress markers 3-nitrotyrosine (3-NT), protein carbonyl (PC), 4-hydroxynonenal (4-HNE) and lipid peroxidation (LPO). Moreover, we assessed production of superoxide (O₂^•-) and hydrogen peroxide (H₂O …

Circumventing Cisplatin Resistance In Ovarian Cancers Through Reactivation Of P53 By Non-Cross-Resistant Platinum Analogs, Michelle Martinez-Rivera

Dissertations and Theses (Open Access)

Abstract

CIRCUMVENTING CISPLATIN RESISTANCE IN OVARIAN CANCERS THROUGH REACTIVATION OF P53 BY NON-CROSS-RESISTANT PLATINUM ANALOGS

Michelle Martinez-Rivera, B.S.

Advisory Professor: Zahid H. Siddik, Ph.D.

Cisplatin (cis-Pt), an anticancer platinum (Pt) drug, is used widely in the treatment of several malignancies, such as ovarian cancer. This Pt compound induces DNA damage, which results in p53 activation through post-translational modifications, mainly phosphorylation, culminating in execution of programmed cell-death. However, despite initial therapeutic response to cis-Pt, clinical resistance to this drug emerges leading to disease progression. Pt-resistance phenotypes have been associated with dysfunction in the p53 signaling pathway. Therefore, an effort to understand …

Characterization Of The Arthropod Communities And Aphid Feeding Behavior Associated With Perennial Warm-Season Grasses (Poaceae) Composition In Nebraska And Wisconsin, Kathryn M. Keller

Department of Entomology: Dissertations, Theses, and Student Research

Switchgrass, Panicum virgatum L., along with two other perennial warm-season grasses, big bluestem (Andropogon gerardii Vitman) and indiangrass, (Sorghastrum nutans L), compose a majority of the grasses found in North American tall grass prairies and have recently received attention as potential bioenergy feedstock. Limited research has been carried out on the relationship of arthropods on these three warm-season grasses in North America. Due to this limited research, the first objective of this research was to document the arthropods associated with switchgrass, big bluestem and indiangrass in Nebraska and Wisconsin over three sampling seasons. More than 10 arthropod orders …

Over-Summering Ecology Of The Wheat Curl Mite (Aceria Tosichella Keifer), Anthony J. Mcmechan

Department of Entomology: Dissertations, Theses, and Student Research

The wheat-mite-virus complex is a consistent and significant threat to winter wheat production in the western Great Plains. This complex consists of three viruses (Wheat streak mosaic virus, Triticum mosaic virus, and Wheat mosaic virus that are transmitted by the wheat curl mite (Aceria tosichella Keifer). Yield impacts from this complex are typically associated with the presence of volunteer wheat that emerges prior to harvest as a result of hail occurring during the heading stages of wheat in early summer. Historical literature on pre-harvest germination has been primarily focused on accelerating breeding programs; however, critical gaps in knowledge exist on …

Methods To Account For Breed Composition In A Bayesian Gwas Method Which Utilizes Haplotype Clusters, Danielle F. Wilson-Wells

Department of Statistics: Dissertations, Theses, and Student Research

In livestock, prediction of an animal’s genetic merit using genomic information is becoming increasingly common. The models used to make these predictions typically assume that we are sampling from a homogeneous population. However, in both commercial and experimental populations the sire and dam of an individual may be a mixture of different breeds. Haplotype models can capture this population structure.

Two models based on breed specific haplotype clusters where developed to account for differences across multiple breeds. The first model utilizes the breed composition of the individual, while the second utilizes the breed composition from the sire and dam. Haplotype …

The Influence Of Peer-Led Team Learning On Underrepresented Minority Student Achievement In Introductory Biology And Recruitment And Retention In Science, Technology, Engineering, And Mathematics Majors, Jeremy David Sloane

Dissertations - ALL

Increasing underrepresented minority (URM) participation in science, technology, engineering, and mathematics (STEM) is of increasing national importance as the United States continues to fall behind other nations in global economic competitiveness. These students constitute a large pool of potential STEM majors at the college level, but they have been recruited to and retained in STEM programs at significantly lower rates than students from other populations. As such, President Barack Obama’s President’s Council of Advisors on Science and Technology (PCAST) has called on undergraduate science instructors to diversify their teaching methods and employ active learning strategies to improve students’ success in …

Animal Water Balance Drives Top-Down Effects In A Riparian Forest-Implications For Terrestrial Trophic Cascades, Kevin E. Mccluney, John L. Sabo

Biological Sciences Faculty Publications

Despite the clear importance of water balance to the evolution of terrestrial life, much remains unknown about the effects of animal water balance on food webs. Based on recent research suggesting animal water imbalance can increase trophic interaction strengths in cages, we hypothesized that water availability could drive top-down effects in open environments, influencing the occurrence of trophic cascades. We manipulated large spider abundance and water availability in 20 × 20 m open-air plots in a streamside forest in Arizona, USA, and measured changes in cricket and small spider abundance and leaf damage. As expected, large spiders reduced both cricket …

A Review On The Invasion Ecology Of Amur Honeysuckle (Lonicera Maackii, Caprifoliaceae), A Case Study Of Ecological Impacts At Multiple Scales, Rachel E. Mcneish, Ryan W. Mcewan

Biology Faculty Publications

Invasive species are of global importance because of their impacts on ecological communities, habitat structure, native community dynamics, and ecosystem processes and function. Scientists and conservation managers are increasingly focusing on the biological impacts of invasive species and on devising management practices that emphasize the health of ecosystems based on measured biological processes. Amur honeysuckle (Lonicera maackii (Rupr.) Herder) is a highly successful invasive shrub in forests of eastern North America. The scientific literature surrounding this species has grown in the past several decades as researchers have investigated L. maackii impacts across multiple ecological scales. In this review we …

Heparin-Peptide Interactions, Jacqueline Anastasia Morris

Graduate Theses and Dissertations

Heparin is a polydispersed sulfated molecule that is part of the family called glycosaminoglycans found in the extracellular matrix and cell surfaces. This molecule is extremely important for the activation of proteins and protein-receptor interactions that are responsible for downstream cell signaling pathways. Heparin has been isolated from porcine intestine and used as an anticoagulant for the prevention of embolisms, heart thrombosis, and clotting during heart surgeries. This so-called miracle drug was in use until 2008, when isolated batches were found to be contaminated with other glycosaminoglycans similar to heparin. From 2008, there has been a dire need for a …

Behavioral Differences Between Native And Exotic Invertebrate Prey Affect Susceptibility To Predation By A Native Amphibian Predator, Zachary Cava

Biology Theses

Invasive species threaten global biodiversity via mechanisms that include altering the dynamics and structure of native food webs. Whereas much research has focused on how exotic species respond to native predators, less is known about how native predators are affected by invasive prey. Here I investigate the response of a rare and threatened native predator—the Eastern Hellbender (Cryptobranchus alleganiensis) to a high-profile invasive crayfish species, Orconectes rusticus. Hellbenders have declined throughout much of their range, and although the potential for exotic predators (i.e. sport fish) to negatively impact C. alleganiensis has been addressed, effects of exotic prey …

Forest Islands In A Sea Of Urban Habitat, Michael J. Olejniczak

Biology Theses

Urban forests are poorly defined as ecological communities. Substantive links between anthropogenic landscape features and forest ecology are lacking. ‘Urbaness’ is commonly defined by human population density or land use classifications, but their use is inconsistent throughout the literature, and rarely is linked with ecological processes. Furthermore, it is unknown whether urban forests are functioning parts of a patchy urban woodland system or isolated islands amidst an ocean of unsuitable habitat. I first used digital satellite imagery and publicly available U.S. National Park data to link urban land use with forest processes. I then linked those land use classifications with …

Levels Of Confidence In Schmieding Center In-Home Caregiving Training, Morena L. Valdizon

Health, Human Performance and Recreation Undergraduate Honors Theses

Abstract

The Schmieding Center for Senior Health and Education offers a unique approach and program designed to teach their students how to care for an older adult in the home. The purpose of this study was to determine the effectiveness of the in-home assistant course on the participant’s confidence levels. It was hypothesized that the confidence levels of the students that enrolled in the in-home assistant training course would increase with the completion of the 40-hour course and that demographic factors such as gender, age, and economic background would impact the levels of confidence. This study was conducted by the …

Amplified Fragment Length Polymorphism (Aflp) Analysis Of Taeniatherum Caput-Medusae, An Invader Of Western U.S. Rangelands, Elizabeth Catherine Kent

Boise State University Theses and Dissertations

Biological invasions are one of the main drivers of global change, and thus one of the main factors contributing to a loss of biodiversity world-wide. Introduced species can destroy habitat through predation, grazing, and competition for resources; spread disease; alter disturbance regimes; and disrupt ecosystem services. Taeniatherum caput-medusae subsp. asperum (medusahead) is a winter-annual grass native to Eurasia and invasive in the westernUnited States. Medusahead dominates one million hectares of its invasive range and detrimentally affects the areas it inhabits through degradation of foraging value for livestock, increasing fire frequencies, and decreasing biodiversity. Previously, allozyme analyses have suggested this …

Improving The Roadside Environment Through Integrating Air Quality And Traffic-Related Data, Christine M. Kendrick

Dissertations and Theses

Urban arterial corridors are landscapes that give rise to short and long-term exposures to transportation-related pollution. With high traffic volumes, congestion, and a wide mix of road users and land uses at the road edge, urban arterial environments are important targets for improved exposure assessment to traffic-related pollution. Applying transportation management strategies to reduce emissions along arterial corridors could be enhanced if the ability to quantify and evaluate such actions was improved. However, arterial roadsides are under-sampled in terms of air pollution measurements in the United States and using observational data to assess such effects has many challenges such as …

Blackbirds, Richard A. Dolbeer, George M. Linz

Wildlife Damage Management Technical Series

The term blackbird loosely refers to a diverse group of about 10 species of North American birds that belong to the avian family Icteridae. The most common species include: Red-winged blackbird (Agelaius phoeniceus) Common grackle (Quiscalus quiscula) Great-tailed grackle (Quiscalus mexicanus) Brown-headed cowbird (Molothrus ater) Yellow-headed blackbird (Xanthocephalus xanthocephalus) Brewer’s blackbird (Euphagus cyanocephalus) Rusty blackbird (Euphagus carolinus) In addition to blackbirds, this family includes orioles, meadowlarks, and bobolinks.

Human-Wildlife Conflicts 1 Damage Identification 3 Management Methods 4 Economics 7 Species Overview 8 Legal Status 11 Glossary …

Double-Crested Cormorants, Brian S. Dorr, Kristi L. Sullivan, Paul D. Curtis, Richard Chipman, Russell D. Mccullough

Wildlife Damage Management Technical Series

The history of conflict between double-crested cormorants (Figure 1) and human interest in fisheries is long and convoluted. Following a low point in the 1970s, populations of cormorants expanded in North America, as did concerns about impacts on fisheries. By the late 1990s, natural resource agencies in 27 states reported losses of free-ranging fish stocks to cormorants. Agencies in 10 states, ranging from the Southwest to the Northeast, considered cormorant predation to be of moderate to major concern to fishery management.

Overall, double-crested cormorants are not major consumers of commercial and sportfish species. However, exceptions have been recorded at specific …

Bird Dispersal Techniques, Thomas W. Seamans, Allen L. Gosser

Wildlife Damage Management Technical Series

Conflicts between humans and birds likely have existed since agricultural practices began. Paintings from ancient Greek, Egyptian, and Roman civilizations depict birds attacking crops. In Great Britain, recording of efforts at reducing bird damage began in the 1400s, with books on bird control written in the 1600s. Even so, the problem persists. Avian damage to crops remains an issue today, but we also are concerned with damage to homes, businesses, and aircraft, and the possibility of disease transmission from birds to humans or livestock. Successful dispersal techniques should capitalize on bird sensory capabilities. If birds cannot perceive the dispersal technique, …

Geese, Ducks And Coots, John L. Cummings

Wildlife Damage Management Technical Series

Canada geese, snow geese, ducks, and American coots all have been implicated in agricultural crop and turf damage. Canada geese and snow geese that graze on winter wheat and rye crops can reduce subsequent grain and vegetative yields. Canada geese also cause serious damage to sprouting soybeans in spring and to standing cornfields in the autumn. The most common damage to agricultural resources associated with geese results from consumption of crops. Other impacts involve unacceptable accumulations of feces in pastures, trampling of emerging crops, and increased erosion and runoff from fields where the cover crop has been grazed. Canada geese …

Identifying And Addressing Soil Property Issues Affecting Roadside Vegetation Establishment, Xu Li, Martha Mamo, Walter H. Schacht, Tala Awada, Humberto Blanco-Canqui

Nebraska Department of Transportation: Research Reports

Attaining adequate vegetation cover along highways is important for NDOR to comply with EPA’s stormwater regulations. However, low plant cover is a common problem on shoulders (first 16 feet off the pavement) of many highways in Nebraska. The ultimate goal of this study is to identify cost-effective engineering solutions that assure adequate seed beds (i.e., soil conditions) for establishment of selected seeding mixtures. The objectives of this study are to (1) characterize the soil properties along roadsides where vegetation stands have not developed well, and (2) verify the effects of select soil property parameters on plant germination and establishment.

Sampling …

The Impact Of Crop Insurance On Indonesian Rice Production, Zaura Fadhliani

Graduate Theses and Dissertations

This study builds a theoretical model of the yield-based MPCI crop insurance policy for a risk averse rice farmer in Indonesia and presents the comparative statics analysis of policy variables on yield through the coupling, wealth, and insurance effects. Moreover, Using yield data from 1979 to 2014 for the Tuban Regency, this study applies numerical optimization to the model and simulates the effects of different policies on input use, certainty equivalents, indemnity payment, and premiums. The theoretical analysis shows that no coupling effect exists for change in the coverage level, while a coupling effect exists for change in the subsidy …

The Update, August-October 2016, University Of Northern Iowa. College Of Humanities, Arts And Sciences.

Update

Inside This Issue:
--CHAS Briefs
--Spotlight-Student: Tsering Kyi
--Spotlight-Faculty: Nikki Harken
--Science in the Media
--Cornerstone Theatre Performance
--Senior Seminar Service
--NSF at UNL
--Calendar of Events

Als Mutant Sod1 Interacts With G3bp1 And Affects Stress Granule Dynamics, Jozsef Gal, Lisha Kuang, Kelly R. Barnett, Brian Z. Zhu, Susannah C. Shissler, Konstantin V. Korotkov, Lawrence J. Hayward, Edward J. Kasarskis, Haining Zhu

Molecular and Cellular Biochemistry Faculty Publications

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease. Mutations in Cu/Zn superoxide dismutase (SOD1) are responsible for approximately 20 % of the familial ALS cases. ALS-causing SOD1 mutants display a gain-of-toxicity phenotype, but the nature of this toxicity is still not fully understood. The Ras GTPase-activating protein-binding protein G3BP1 plays a critical role in stress granule dynamics. Alterations in the dynamics of stress granules have been reported in several other forms of ALS unrelated to SOD1. To our surprise, the mutant G93A SOD1 transgenic mice exhibited pathological cytoplasmic inclusions that co-localized with G3BP1-positive granules in spinal cord motor neurons. …

Green Tea Polyphenols Inhibit The Growth Of The Dental Cavity Causing Bacteria Streptococcus Mutans, Amy Lynn Melok

Theses, Dissertations and Culminating Projects

An often overlooked disease, dental caries, or cavities, is one of the most prevalent infectious diseases across the globe. Streptococcus mutans (S. mutans) is the main etiological bacteria present in the oral cavity that leads to dental caries. All of the S. mutans in the oral cavity try to pool together to form an intelligent biofilm that adheres to the surfaces of teeth. S. mutans thrive on the sugary foods we eat and release acid by products that aid in the wearing away of the teeth’s enamel. As this enamel begins to wear away, the decaying process begins and cavities …

The Effect Of R382w Mutation On Citrus Paradisi Flavonol Specific 3-O-Glucosyltransferase, Kathleen King

Undergraduate Honors Theses

Flavonoids are a class of plant metabolites with C6-C3-C6 structure responsible for many biological functions, including coloration and defense. Citrus paradisi, grapefruit, contains a wide variety of flavonoids which are grouped by the extent of modification, examples of which are flavonols, flavones, and flavanones. A major modification is the addition of glucose by glucosyltransferases (GTs) to stabilize the structure and provide ease of transport. Glucosyltransferases can be highly substrate and regiospecific. With Cp3OGT, glucose is added at the 3-hydroxy position. This 3GT only accepts flavonols as its substrate; however, a Vitis vinifera (grape) 3-GT can accept both flavonols and …

Reconstitution Of Munc18-Dependent Mast Cell Degranulation, Matthew Grant Arnold

Master's Theses

Mast cells are specialized secretory leukocytes that play diverse roles in the body, mediated by release of histamine and other pharmacologically active substances. Although offering essential protection in innate and adaptive immunity, mast cells are also essential to the progression of inflammatory diseases, including allergy and asthma, (Theoharides et al., 2012). Exocytosis of pro-inflammatory mast cell mediators in response to otherwise innocuous antigens relies on evolutionarily-conserved membrane fusion machinery. These proteins, called SNAREs are regulated by the Sec1/Munc18 (SM) protein family (Axle Lorentz, Baumann, Vitte, & Blank, 2012). Mast cells express three mammalian Munc18 isoforms (a, b, and c), which …

Effects Of Fire On Soil Co₂ Efflux In A Mature Longleaf Pine Forest, Knox Lemee Flowers

Master's Theses

This study was conducted from 2012-2013 in a 96 year old longleaf pine at the Lake Thoreau Environmental Center located Lamar County, MS. Measurements of soil CO₂ efflux (i.e., soil respiration or SR) rates (µmol m^-2 sec^-1) were taken across 8 field plots (4 burned, 4 unburned) before and after a prescribed fire on that occurred in May, 2012. These measurements were taken over diurnal cycles using a LICOR LI-8100A automated soil gas flux system with long term chambers. SR rates and soil temperature measurements were collected during 3 sampling periods in 2012 and 1 sampling period …