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Nondrug Reinforcement Loss And Relapse To Alcohol Seeking In Another Context, Adam D. Pyszczynski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Extinguished alcohol-maintained responding has been shown to relapse in a
resurgence preparation when food-reinforced responding is subsequently extinguished within the same context. However, drug and nondrug reinforcers are often specific to different contexts. Accordingly, the present experiments sought to determine whether loss of an alternative source of nondrug reinforcement in one context could produce relapse to drug seeking in a separate context. In one experiment, rats made topographically different responses for food or alcohol in alternating components of a multiple schedule. Both reinforcers were delivered during baseline, alcohol was withheld during the second phase of the experiment, and finally both …

Comparative Studies On Scale-Up Methods Of Single-Use Bioreactors, Emily B. Stoker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was performed to increase knowledge of oxygen mass transfer (kLa) and mixing times in the scale-up of disposable bioreactors.Results of oxygen mass transfer studies showed kLa to increase with increasing agitation and aeration rates. By maintaining a scale-up constant such as gassed power to volume or shear, an almost constant k_La was achieved during scale-up from 50 to 2000 L. Using the scale-up constant P_g/V resulted in statistically higher kLa values at greater reactor volumes. Mixing times were revealed to be significantly affected by agitation, but not by the aeration rates tested. No pattern …

Three Essays On The Economic Impact Of Bovine Spongiform Encephalopathy In The United States, Rachna Gollamudi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The first native-born case of Bovine Spongiform Encephalopathy (BSE or commonly known as Mad Cow Disease) in North American continent was reported on 20 May 2003 in central Alberta, Canada. The first case of BSE in the United States was announced on 23 December 2003.

My dissertation is divided into three essays on the economic impact of the outbreak of Bovine Spongiform Encephalopathy (BSE) in the United States in December 2003. The first essay focuses on quantifying the impact of the outbreak of BSE in the United States and Canada on the stock returns of major publicly traded agribusiness firms …

Animal Performance And Diet Quality While Grazing Corn Residue, Jennifer A. Gigax

Department of Animal Science: Dissertations, Theses, and Student Research

Grazing cattle on corn residue as a winter feed source has become an integral part of many Nebraska producers’ management plans. Utilizing corn residues extends the grazing season and is often more economical than grazing winter range or dry lot situations. Corn residue is high in OM and NDF, moderate in digestibility, and low in CP. Cattle grazing corn residues may need to be supplemented with a protein source to meet requirements. The development and application of DNA technology to create new corn hybrids has improved yields with fewer inputs, leading to a continued low cost food supply for consumers. …

The Logic Of The ‘As If’ And The Existence Of God: An Inquiry Into The Nature Of Belief In The Work Of Jacques Derrida, Colby Dickinson

Theology: Faculty Publications and Other Works

The religious thematics at play in the work of Jacques Derrida have often provided an ongoing platform from which to struggle with the entire scope of his work, thus moving the seemingly peripheral discourses on religion within his oeuvre to the center stage. Despite repeated attempts to come to terms both theologically and philosophically with the conditional nature of representations, the problematics of representation are perhaps nowhere more forcefully demonstrated than in the work of Derrida. Indeed, for Derrida, the ‘as if’, as a regulative principle directly appropriated and modified from its Kantian context, becomes the central lynchpin for understanding, …

The Importance Of Undecideds In The Evolution Vs. Creationism Debate, Seth Steinman

Senior Honors Projects

As a scientific theory, evolution has as much empirical support for its core assertions as the heliocentric universe theory or the belief that the Earth is round.  Despite a unanimous consensus in the scientific community about evolution’s validity, the General Social Survey (GSS) consistently reports that 85 percent of Americans are either undecided or do not believe in evolution.

This divide between evolutionists, led by scientists, and creationists, led by religious leaders, has enormous scientific and political implications, which include funding for basic scientific research, acting to stop global warming, and what schools should be teaching our children.

The most …

Child Advocacy Centers And Child Sexual Abuse In Nevada, Chrystal Ruggieri

UNLV Theses, Dissertations, Professional Papers, and Capstones

Child sexual abuse has gained significant attention from the medical, legal and social research communities over the last couple decades. Developed in the 1980s, Child Advocacy Centers (CACs) have been noted as one of the leading developments in combating child sexual abuse. Child Advocacy Centers bring together multi-disciplinary teams in a child friendly environment to improve resources for abused children and their families as well as aid in prosecution. The majority of states across the country have adopted aggressive legislation and funding initiatives to aid in protecting this vulnerable population. This study analyses Nevada's position on childhood sexual abuse and …

Characterization Of The Phytochelatin Synthase Of Schistosoma Mansoni, Debalina Ray, David L. Williams

Faculty Publications – Biological Sciences

Treatment for schistosomiasis, which is responsible for more than 280,000 deaths annually, depends exclusively on the use of praziquantel. Millions of people are treated annually with praziquantel and drug resistant parasites are likely to evolve. In order to identify novel drug targets the Schistosoma mansoni sequence databases were queried for proteins involved in glutathione metabolism. One potential target identified was phytochelatin synthase (PCS). Phytochelatins are oligopeptides synthesized enzymatically from glutathione by PCS that sequester toxic heavy metals in many organisms. However, humans do not have a PCS gene and do not synthesize phytochelatins. In this study we have characterized the …

Examining The Effects Of Reinforcement Context On Relapse Of Observing, Eric A. Thrailkill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Attentional biases occur with various psychological disorders, including drug addiction and anxiety. Conditioned reinforcement likely plays a role in maintaining attentional biases to stimuli associated with reinforcement for unwanted behavior. The observing-response procedure is considered a model of attending as reflected by responding maintained by conditioned reinforcement. Effects of primary reinforcement on the persistence of observing have been studied in the framework of behavioral momentum theory. Studies have shown observing-responses to be more resistant to
change in contexts arranging relatively higher rates of primary reinforcement. Recently, behavioral momentum theory has been extended to describe the effects of primary reinforcement context …

Testing The Efficacy Of Merrill’S First Principles Of Instruction In Improving Student Performance In Introductory Biology Courses, Joel Lee Gardner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

One learning problem is that public understanding of science is limited. Many people blame at least part of the problem on the predominant lecture approach for students' lack of science understanding. Current research indicates that more active instructional approaches can improve student learning in introductory undergraduate biology courses. Active learning may be difficult to implement because methods and strategies, ranging from in-class collaborative problem-solving to out of class multimedia presentations, are diverse, and sometimes difficult to implement. Merrill's First Principles of Instruction (hereafter referred to as "First Principles" or "First Principles of Instruction") provides a framework for implementing active learning …

Graphshop: An Interactive Software Environment For Graph Theory Research And Applications, Aaron Andersen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Graph Theory is the mathematical study of the structure of abstract relationships between objects. Although these constructions (graphs) are themselves purely theoretical, their ability to model pair-wise relationships in systems of arbitrary complexity yields abundant direct correspondence with numerous important physical and societal systems in the real world. Additionally, the simple discrete nature of fundamental graph structures allows for easy pseudo-geometric visualization of graphs in a wide variety of ways. Taken together, these two properties suggest that graph theory teaching, research, and applications would benefit greatly from the use of a unified software environment for graph construction, interaction, and visualization. …

Stress Response And Pathogenesis Of Salmonella Enterica Serovar Typhimurium, Jigna D. Shah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Salmonella is a food-borne pathogen that leads to substantial illness worldwide. The clinical syndromes associated with Salmonella infection are enteric (typhoid) fever and gastroenteritis, in healthy humans. Typhoid fever is caused by host-adapted S. Typhi and S. Paratyphi. Gastroenteritis is caused by serovars usually referred to as non typhoidal Salmonellae (NTS). In recent years, an increasing number of outbreaks due to NTS, despite increased efforts in food safety, were reported because of persistence of Salmonella in the food chain. Thus I hypothesized that Salmonella is able to withstand stresses in the environment and treatments used during food processing …

A Study On The Applications And Toxicity Assessments Of Carbon Nanotubes In Tissue Engineering, Rena Baktur

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Carbon nanotubes (CNTs) are one of the most popular nanomaterials. There has been increasing interest in the development and applications of carbon nanotubes due to their huge potential in industrial and medical applications. Recent applications of carbon nanotubes include development of scaffolds and drug delivery systems. Despite rapidly emerging applications of CNTs, little is known about the impact of CNTs on cellular processes, especially mesenchymal stem cell (MSC)'s differentiation. Also, the effects of nanoparticle exposure under different conditions on cellular responses have not been well characterized yet.

To characterize the effects of CNTs on creating nanoscale scaffolds for tissue engineering, …

15n Tracer And Modeling Analyses Of Nutrient Transport Through Lakes In A Subalpine Watershed, David M. Epstein

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lakes have historically been overlooked as important nutrient processors within their watersheds. In general ecologists have focused on streams as zones of uptake and transformation, while viewing lakes as simple nutrient traps. However, recent research has highlighted the large influence that lakes may have on water chemistry within their watersheds. Within the field of limnology, researchers have traditionally focused on the pelagic zone for in-lake production. Further research in shallow lakes has highlighted the role benthic production within the littoral zone plays in the lake ecosystem. The greater influence of lakes is highlighted when comparing watersheds containing lakes with watersheds …

Preventative Behavioral Parent Training: A Preliminary Investigation Of Strategies For Preventing At-Risk Children From Developing Later Conduct Problems, Jessica L. Malmberg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Children exhibiting conduct problems comprise the largest source of referrals to children's mental health services in this county. Significant research has been conducted in an attempt to identify specific risk factors that result in increased vulnerability of a child developing conduct problems. Knowledge of these factors increases our ability to identify young children who are at greater risk for developing conduct problems. The treatment for conduct problems that possesses the greatest amount of empirical support is behavioral parent training. Yet behavioral parent training fails to address behaviors and risk factors that are present during a child's early development. Preventative behavioral …

Basic Concepts In Early Education Programs For Children With Hearing Loss In Listening And Spoken Language Classrooms, Katherine L. Powell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mastery of basic concepts is an academic building block for preschool children in early education programs. Research shows that understanding basic concepts (e.g. top, under, fast, now, all, behind, full and short) is important for academic success and higher order thinking. Experts in the field of concept acquisition agree on six strategies for teaching basic concepts. These strategies include: using positive examples and negative examples, highlighting critical features of concepts through continuous conversion, isolating the concept, the order in which the examples are presented, and teaching generalization. This study investigated the extent to which nine preschool teachers of children with …

Investigating The Strategies To Improve The Quality Of Low-Fat Mozzarella And Cheddar Cheeses, Ranjeeta Wadhwani

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ranjeeta Wadhwani in supervision of Dr. D. J. McMahon, has worked on investigating the various strategies to improve three qualities of low-fat cheeses. These three qualities were meltability, color, or feasibilities to incorporate dietary fiber into the low-fat cheese with its simultaneous effect on texture. There has been an ongoing research on improving the quality of low-fat cheese. In our study, low-fat Mozzarella cheese curds of 4 different fat content (1.5, 3.0, 4.5, and 6.0%) were comminuted and externally added with melted butter in the amount to get 6% fat in final cheese for low-fat claim. Addition of melted butter …

Exploring The Relationship Between Place Identity And Personalization Of Space In Temporary Student Housing, Joshua H. Rowley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study is to better understand the relationship between the personalization of one’s physical environment and the degree of place identity the person has toward their space, specifically those living in temporary student housing. There have been several studies on peoples’ inherent need to personalize their space. While previous research has identified key factors that help to define place identity in general, this study addresses the fact that not much has been said about how people in temporary housing, specifically student housing, actually go about creating their living spaces.

The key issues this research addressed were the …

Ecology And Conservation Of Cougars In The Eastern Great Basin: Effects Of Urbanization, Habitat Fragmentation, And Exploitation, David C. Stoner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research was designed to investigate cougar response to urbanization, habitat fragmentation, and exploitation from behavioral, demographic, and landscape perspectives. The source-sink model has been proposed as an alternative framework for the management of exploited cougar populations. I addressed the basic question of whether cougars conform behaviorally to the predictions of the source-sink model, and consequently, the applied question of whether the model could be used for the conservation of this species. To achieve this I evaluated three scale-specific questions using radio-telemetry and hunter-harvest data collected from 1996-2010. At the subpopulation scale, I tested the hypothesis that cougars are wildland …

Global 4-H Network: Laying The Groundwork Survey, Jennifer Major

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A descriptive study examining 4-H programs in Africa, Asia, and Europe was conducted for the National 4-H Council. Program size, scope, structure, organization, and funding varied greatly by country and few of the programs were connected to a university, but many partnered with other 4-H organizations around the world. Program participants were found to be primarily male with few programs specifically for women. A list of content areas provided by the 4-H programs was also obtained and compared to top agricultural commodities in their country. Very few content areas offered by the country aligned with their major agricultural commodities even …

Quantitative Genetic Analysis Of Reproduction Traits In Ball Pythons, Benson H. Morrill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although the captive reproduction of non-avian reptiles has increased steadily since the 1970’s, a dearth of information exists on successful management practices for large captive populations of these species. The data reported here come from a captive population of ball pythons (Python regius) maintained by a commercial breeding company, The Snake Keeper, Inc. (Spanish Fork, UT). Reproductive data are available for 6,480 eggs from 937 ball python clutches. The data presented suggest that proper management practices should include the use of palpation and/or ultrasound to ensure breeding occurs during the proper time of the female reproductive cycle, and …

Evaluating The Effects Of Reinforcer Choice And Reinforcer Variation On The Response Rates Of Children With Autism, Alice Ann Keyl Austin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Motivating individuals with autism can be challenging for clinicians and educators seeking to increase skills or decrease problem behaviors. Even when highly preferred reinforcers have been identified, they tend to lose their effectiveness over time. Over the years, several strategies have been developed to maintain the effectiveness of reinforcers. Reinforcer variation has been demonstrated to attenuate decreases in responding associated with repeated exposure to a single reinforcer. Another strategy that has been used to help maintain responding is allowing an individual a choice among reinforcers. Several researchers have suggested that providing choice among several reinforcers may produce the same effects …

Process-Based Management Of Downy Brome In Salt Desert Shrublands: Assessing Pre- And Post- Rehabilitation Soil And Vegetation Attributes, Merilynn Carol Hirsch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As an ecosystem driver, downy brome (Bromus tectorum L.) presents obstacles to land rehabilitation efforts, including restoring desirable species cover. Because damaged ecosystems may have crossed both abiotic and biotic thresholds, ecologically-based control strategies may assist with altering successional trajectories and restoring desirable plant species. My thesis research had three objectives: 1) assess soil and vegetation relationships in degraded salt desert ecosystems prior to implementing downy brome control treatments, 2) determine the effects of control treatments on soil properties and resident plant species, and 3) evaluate the relative importance of shrubland soil type, herbicide type, and herbicide rate on seedling …

Causes, Extent, And Consequences Of Lead-Pellet Ingestion By Chukars (Alectoris Chukar) In Western Utah: Examining Habitat, Search Images, And Toxicology, R. Justin Bingham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lead ingestion adversely affects humans and over 130 species of wildlife. Wild chukars (Alectoris chukar) are documented to ingest lead, but the causes and consequences of this ingestion are poorly understood. The objectives of this research were to 1) examine the influence of habitat use, the hunting season, and seasonal climate on the extent and severity of lead ingestion by chukars in western Utah, 2) assess the effects of habitat use, feeding behaviors, and lead density on the causes of lead-pellet ingestion in captive and wild chukars, and 3) investigate the consequences of lead-pellet ingestion in captive chukars as a …

A Mark–Recapture Technique For Monitoring Feral Swine Populations, Matthew M. Reidy, Tyler A. Campbell, David G. Hewitt

United States Department of Agriculture Wildlife Services: Staff Publications

Techniques to monitor populations of feral swine (Sus scrofa) relative to damage control activities are needed on rangelands. Our objectives were to describe and assess a mark–recapture technique using tetracycline hydrochloride (TH) for monitoring feral swine populations. We established bait stations at study sites in southern and central Texas. During 1 d, we replaced normal soured corn bait with bait containing TH and counted the number of feral swine that consumed bait with observers. We conducted feral swine removal using box-style traps and helicopters, at which time we collected teeth for TH analysis. In southern Texas, we estimated …

Use Of Shallow Estuarine Habitats By Nekton In The Mobile-Tensaw River Delta, Alabama, Lawrence P. Rozas, John F. Valentine, Charles Martin, Latina Steele

Biology Faculty Publications

We compared nekton density, composition, and biomass in fall 2009 and spring 2010 among three major habitat types (marsh, SAV=submerged aquatic vegetation dominated by Vallisneria americana, SNB=shallow nonvegetated bottom) commonly found throughout the Mobile-Tensaw River Delta (MTD) using 1-m2drop samplers. In the sampling design, habitat selection was based on vegetation composition. Sample locations (TR=Tensaw River, CB=Chocolatta Bay, and BC=Below Causeway) were selected based on their degree of tidal connectivity with the wider estuary (BC > TR > CB). Nekton distributional patterns varied among both locations and habitat types. Species richness was greater at BC than CB. The young of most …

(Re)Constituting The Immigrant Body Through Policy: A Rhetorical Analysis Of The Narratives Within The Discourses Of The Development, Relief, And Education For Alien Minors Act (Dream Act), Emily Rae Ironside

Graduate Theses and Dissertations

Using the testimonies surrounding the Development, Relief, and Education for Alien Minors Act (DREAM Act) as a primary case study, this project provides a rhetorical investigation of the interplay between narratives, nation building, national identity, policymaking, and the American immigrant. This project first identifies the grand narrative of exclusionary nationalism as the primary narrative constituting the American identity. Then, this project examines the rhetoric of policymakers to demonstrate how an Anglo-Saxonized, elitist notion of American identity is rhetorically constituted by assimilationist, racist, xenophobic, and classist discourses. Moreover, it argues policymakers maintain the narrative dominance of exclusionary nationalism through restrictive immigration …

Synthesis, Characterization, And Reactivity Of Biologically Relevant Copper(I) Selone And Thione Complexes, Martin Kimani

All Dissertations

In Fenton-like reactions, Cu+ localized on DNA reduces hydrogen peroxide to form hydroxyl radical (*OH), resulting in oxidative DNA damage. This DNA damage causes mutation and cell death, which can lead to diseases such as cancer, Alzheimer's, and arteriosclerosis. Sulfur and selenium antioxidants have been investigated for the prevention and treatment of these diseases, and studies have shown that sulfur- and selenium-containing antioxidants prevent DNA damage from copper-generated hydroxyl radical and that metal coordination is required for the observed antioxidant activity.
To determine how copper coordination results in DNA damage inhibition, Cu+ complexes with selone and thione ligands were synthesized …

Cellulose Nanocrystals Properties And Applications In Renewable Nanocomposites, Esteban Urena Benavides

All Dissertations

Development of novel bio-based nanocomposites is fundamental to reduce the dependence on fossil resources and provide a sustainable future. In light of this global problem, cellulose nanocrystals (CNCs) have raised interest due to their remarkable mechanical properties. Adequate design of nanocomposites requires a fundamental understanding of how the structure affects the mechanical properties of the material. However, contradictory results in the literature have revealed a lack of comprehension of this relationship for CNC based composites. Consequently, this work provides an explanation to unusual results for CNC nanocomposites presented in the literature and demonstrates the ability to achieve property enhancements in …

Characterization Of Piedmont Prairie Sites In North And South Carolina, James Benson

All Dissertations

Grassland habitats have essentially disappeared from the Piedmont. This study was conducted to determine which site characteristics in remnant Piedmont prairie sites could be used as indicators of suitable sites. Eight prairie remnant sites located in the Piedmont of North and South Carolina were evaluated based on soil series, slope, aspect, landform index, temperature, and precipitation. Geographic Information System technology was used to create layers of these characteristics to predict potential restoration sites throughout the North and South Carolina Piedmont. It was found that southern aspects, slopes generally less than 15%, upper slope positions, and occurrence on Enon (Fine, mixed, …