Digital Commons Network^™

Modeling Nitrogen Loss From Regional Switchgrass Agriculture, Saumya Sarkar

All Theses

A water quality modeling study was conducted to determine and compare nitrogen loss from agricultural systems growing switchgrass and cotton in the southeastern USA. The water quality impacts were modeled at the plot scale and at the watershed scale. The Soil and Water Assessment Tool (SWAT) was used to replicate field conditions observed at switchgrass research plots at Pee Dee Research and Educational Center at Florence, South Carolina. The plot scale modeling suggested that in the early years of growth there is significant nitrogen loss from switchgrass to streamflow and groundwater but they are significantly less as the switchgrass matures. …

An Examination Of The Leave No Trace Visitor Education Program In Two Us National Park Service Units, Wade Vagias

All Dissertations

The purpose of this dissertation was to examine overnight National Park Service (NPS) backcountry visitors' behavioral intentions to comply with promoted LNT principles as well as their opinions regarding the efficacy of various LNT education delivery strategies. Leave No Trace is the most pervasive outdoor skills and ethics training program addressing human powered recreationists in existence however, empirical investigations into the efficacy and diffusion of the program have been scant to nonexistent.
The study sample was obtained by intercepting visitors at backcountry permit issuing stations in Glacier National Park (GNP) in northwest Montana and Olympic National Park (ONP) in northwest …

Genomic, Proteomic And Metabolomic Approaches To Study Drought Responses In Aquilegia, David Henry

All Dissertations

Global population is expected to increase 30% by 2040, which will result in an increased need for crop production to feed the growing population. Combined with projected increased drought conditions worldwide, plant genetic research is necessary to gain a deeper knowledge of the molecular factors involved in plant drought response in order to engineer crop species with improved drought tolerance. Aquilegia has been recently developed as a model species for gene exploration based on its ability to thrive in a wide variety of environments including arid locations. An attractive asset of Aquilegia is its evolutionary position, equidistant between rice and …

Creation Of Defined Single Cell Resolution Neuronal Circuits On Microelectrode Arrays, Russell Pirlo

All Dissertations

The way cell-cell organization of neuronal networks influences activity and facilitates function is not well understood. Microelectrode arrays (MEAs) and advancing cell patterning technologies have enabled access to and control of in vitro neuronal networks spawning much new research in neuroscience and neuroengineering. We propose that small, simple networks of neurons with defined circuitry may serve as valuable research models where every connection can be analyzed, controlled and manipulated.
Towards the goal of creating such neuronal networks we have applied microfabricated elastomeric membranes, surface modification and our unique laser cell patterning system to create defined neuronal circuits with single-cell precision …

Influences During Student Teaching On Preservice Teachers' Attitudes Toward The Inclusion Of Students With Disabilities In The General Education Classroom, Jennifer J. Huber

All Dissertations

The purpose of this research project was to explore the influences during fieldwork on preservice teachers' attitudes towards the inclusion of students with disabilities in the general education classroom. An embedded, mixed-methods design was used to examine both qualitative and quantitative data. Preservice teachers completed the Opinions Relative to the Integration of Students with Disabilities (Antonak & Larrivee, 1995) survey before beginning full-time student teaching. This survey measured their attitudes towards the inclusion of students with disabilities in the general education classroom. In addition, student teachers completed the Teachers' Sense of Efficacy Scale (Tschannen-Moran & Hoy, 2001) prior to their …

Reaction-Diffusion Systems With A Nonlinear Rate Of Growth, Yubing Wan

Theses and Dissertations - UTB/UTPA

In the literature there are quite a few elegant approaches which have been proposed to find (he first integrals of nonlinear differential equations. Recently, the modified Prelle-Singer method for finding the first integrals of second-order nonlinear ordinary differential equations (ODEs) has attracted considerable attention. Many researchers used this method to derive the first integrals to various systems. In this thesis, we are concerned with the first integrals for reaction-diffusion systems with a nonlinear rate of growth. Under certain parametric conditions we express the first integrals explicitly by applying an analytical method as well as the modified Prelle-Singer method.

A Dna Approach To The Road-Coloring Problem, Arindam Roy

Theses and Dissertations - UTB/UTPA

The Road-Coloring Problem in graph theory can be stated as follows: Is any irreducible aperiodic directed graph with constant outdegree 2 road-colorable? In other words, does such a graph have a synchronizing instruction? That is to say: can we label (or color) the two outgoing edges at each vertex, one with “b” or blue color and the other with “r” or red color, in such a manner that there will be an instruction in the form of a finite sequence in “b”s and “r”s (example: rrbrbbbr) such that this instruction will lead each vertex to the same “target” vertex? This …

National Urban Database And Access Portal Tool, Nudapt, Jason Ching, Michael Brown, Steven Burian, Fei Chen, Ron Cionco, Adel Hanna, Torrin Hultgren, Timothy Mcpherson, David J. Sailor, Haider Taha, David Williams

Mechanical and Materials Engineering Faculty Publications and Presentations

Based on the need for advanced treatments of high resolution urban morphological features (e.g., buildings, trees) in meteorological, dispersion, air quality and human exposure modeling systems for future urban applications, a new project was launched called the National Urban Database and Access Portal Tool (NUDAPT). NUDAPT is sponsored by the U.S. Environmental Protection Agency (USEPA) and involves collaborations and contributions from many groups including federal and state agencies and from private and academic institutions here and in other countries. It is designed to produce and provide gridded fields of urban canopy parameters for various new and advanced descriptions of model …

Mechanisms For Temporal Change In Phytoplankton Composition In San Luis Obispo Bay California, Marc T. Tognazzini

Master's Theses

Coastal topography and more specifically, the impact of local hydrography can significantly influence phytoplankton dynamics along the California coast. In San Luis Obispo Bay California, the local hydrography is influenced by the presence of a lee and proposed upwelling shadow in the northwest corner of the bay. These conditions allow for periods of unperturbed phytoplankton growth creating phytoplankton incubation areas. Phytoplankton dynamics including accumulation, advection, and composition were examined in San Luis Obispo Bay California from January to June 2004 using all the primary techniques of ocean monitoring encompassed in the coastal module of the Global Ocean Observing System. These …

H. Pylori Infection In Children: Population-Based Age-Specific Prevalence And Risk Factors In A Developing Country, Wasim Jafri, Javed Yakoob, Shahab Abid, S Siddiqui, Nasim Jafri, Safia Awan, Shaikh Qamaruddin Nizami

Section of Gastroenterology

No abstract provided.

Assessing Recall, Conceptualization, And Transfer Capabilities Of Novice Biochemistry Students' Across Learning Style Preferences As Revealed By Self-Explanations, Jacqueline Hilsenbeck-Farjardo

Dissertations

No abstract provided.

Metamorphism And Putative Bioalteration Of Basaltic Glass : Coast Range Ophiolite, Cynthia E. Schultz

Master's Theses

No abstract provided.

The Role Of Temperature And Desiccation Stress In Limiting The Local-Scale Distribution Of The Owl Limpet, Lottia Gigantea, Luke P. Miller, Christopher D. G. Harley, Mark W. Denny

Faculty Publications, Biological Sciences

1 Small-scale distributions of rocky intertidal organisms may be determined in part by temperature and desiccation stress during low tide and the ability of organisms to resist such stresses. Biophysical modelling techniques, coupled with data on the physiological tolerance of organisms can be used to predict the frequency and severity of abiotic stress events.

2 The limpet Lottia gigantea is a major competitor for primary space on rocky shores along the west coast of North America. The goal of this study was to quantify the thermal and desiccation tolerance of this species and to predict the frequency of stressful events …

Physiology, Regulation, And Pathogenesis Of Nitrogen Metabolism In The Opportunistic Fungal Pathogen Candida Albicans, Suman Ghosh

School of Biological Sciences: Dissertations, Theses, and Student Research

Candida albicans is an opportunistic polymorphic fungus that causes clinically important disease candidiasis to humans. Being polymorphic C. albicans can grow in yeast, hyphae, or pseudohyphae forms and the switch from one form to another is required for virulence. The morphological transitions from one phase to another are carefully orchestrated events which are regulated by several signal transduction pathways. Several environmental factors determine the morphology of the fungus C. albicans. For example growth at lower temperature ~30 ºC, in preferred nitrogen sources cause the fungus to grow as yeasts while at higher temperature ~37 ºC and in poor nitrogen …

Self-Actualization In The Lives Of Medieval Female Mystics: An Ethnohistorical Approach, Cherel Jane Ellsworth Olive

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation explores the cultural and psychological factors that permitted six medieval female mystics to assume positions of leadership and innovation in a world marked by extreme gender inequality. Women religious have often been charged with being neurotics, hysterics, narcissists, and nymphomaniacs whereas males with similar experiences are rarely subject to the same degree of criticism. It is argued here that the women may well have been seeking to achieve the form of self-actualization described by humanist psychologist, Abraham Maslow, as a result of the "conversion" experience analyzed by William James. Furthermore, applying modern categories of mental illness to these …

Exploring Erotic Plasticity As An Individual Difference Variable: Theory And Measurement, Lorraine Benuto

UNLV Theses, Dissertations, Professional Papers, and Capstones

Baumeister's theory of female erotic plasticity is supported by a significant body of data suggesting that female sexuality is more malleable and more greatly influenced by cultural and contextual factors than male sexuality. Sex differences notwithstanding, it is reasonable to theorize that erotic plasticity might also vary across individuals. Based on a thematic/conceptual organization of relevant current literature, we explored erotic plasticity as optimally encompassed by six dimensions: (1) changes in sexual attitudes over time, (2) changes in sexual behaviors over time and across context, (3) fluidity of sexual behaviors along a same-sex/opposite-sex continuum (evidence of attraction and/or sexual involvement …

Assessing Threat Of Introduction Of The Parthenogenetic Marbled Crayfish Marmorkrebs Into North American Waters, Stephanie A. Jimenez, Zen Faulkes

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Background/Question/Methods

Marmorkrebs are parthogenetic crayfish in the genus Procambarus. Their provenance is unknown, but they were discovered in hobbyists' aquaria in Germany in the mid 1990s, and have since been introduced into the North American pet trade. Marmorkrebs are a potential invasive pest species. For example, they have already been introduced into Madagascar, where they may threaten endemic crayfish species. We are trying to estimate the risk, and possible consequences, of any accidental introduction of Marmorkrebs into North American waters. First, we conducted an online survey of hobbyists who keep Marmorkrebs as pets to estimate how widely, and how …

Using Bald Eagles To Track Spatial And Temporal Trends Of Contaminants In Michigan's Aquatic Systems, Michael Ray Wierda

All Dissertations

The bald eagle (Haliaeetus leucocephalus) is an extensively researched tertiary predator. Studies have delineated information about its life history and the influences of various stressors on reproduction. Due to the bald eagles position at the top of the food web, it is susceptible to biomagnification of a wide array of xenobiotics. In Michigan the bald eagle population has recovered strongly since the population bottle-neck of the 1960s. In the 1960s when Michigan's eagle population was first being monitored less than 100 nests were occupied yearly (i.e., active breeding pairs existed). Today there are approximately 500 occupied nests each year and …

Teacher-Student Interactions And Domain-Specific Motivation: The Relationship Between Students' Perceptions Of Teacher Interpersonal Behavior And Motivation In Middle School Science, Julie Brockman Smart

All Dissertations

This study examined interactions between middle school science students' perceptions of teacher-student interactions and their motivation for learning science. Specifically, in order to better understand factors affecting middle school students' motivation for science, this study investigated the interactions between middle school students' perceptions of teacher interpersonal behavior in their science classroom and their efficacy, task value, mastery orientations, and goal orientation for learning science. This mixed methods study followed a sequential explanatory model (Cresswell & Plano-Clark, 2007). Quantitative and qualitative data were collected in two phases, with quantitative data in the first phase informing the selection of participants for the …

Investigation Of Ecological Behavior Of Two Coccinellidae Beetle Adults For Biological Control, Folukemi Ebunoluwa Adedipe

Graduate Theses, Dissertations, and Problem Reports (ETD)

The use of natural enemies is an effective strategy to control and suppress pest populations in a given agroecosystem; however farmers are not motivated to adopt this method because of the high cost and temporal unavailability of natural enemies. This thesis reports findings of a series of laboratory experiments carried out to investigate ecological behavioral of two major natural enemies; Harmonia axyridis and Cryptolaemus montrouzieri (Coleoptera: Coccinellidae) Laboratory studies was conducted to determine if H. axyridis could be attracted to companion plants with different olfactory and visual cues, to investigate the within-plant distribution of long-tailed mealybug, Pseudococcus longispinus (Hempitera: Pseudoccoccidae), …

The Development And Nutritional Characteristics Of An Omega-3-Enhanced Egg Product, Nissan Michelle Kassis

Graduate Theses, Dissertations, and Problem Reports (ETD)

Novel, nutritionally-enhanced egg product was developed by substituting saturated fat and cholesterol-containing yolk with omega-3 fatty acids-rich (o-3 FA) flaxseed, menhaden, algae, and krill oils. The o-3 FA-fortified eggs are typically developed through alteration of hen feed. However, the present study aimed at creating such a product via processing. Experimental batters were developed to match composition, color, and texture of hen eggs (whole egg). The batters, whole egg, and liquid egg product (egg beaters) were cooked, analyzed, and compared. Moisture, protein, and fat content of experimental eggs matched (P>0.05) whole egg. Nutritionally, amino acid profile (AAP) analysis showed no …

Improvement Of The Physical And Nutritional Quality Of Pelleted Feed, Curran Kenji Gehring

Graduate Theses, Dissertations, and Problem Reports (ETD)

Experiments were conducted to improve the physical and nutritional quality of pelleted feed. One experiment focused specifically on improvement of pellet quality using functional muscle proteins. A second experiment examined the effects of increasing mixer-added fat (MAF) on feed manufacture variables, broiler performance variables and carcass composition. In experiment 1, muscle proteins (myofibrillar and sarcoplasmic) were recovered using isoelectric/solubilization precipitation, and a functional paste (TPP) was formed by mixing recovered proteins with typical surimi additives. Trout protein paste was included in broiler diets at 0, 2.5 or 5%. A tap water treatment (3.9%) was included to match the moisture added …

Adoption Levels Of Integrated Pest Management Among Corn Producers In West Virginia, Hari K. Vommi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Modernization of agriculture has exponentially increased the use of pesticides in the last six decades. Pesticides were considered to be the only solution to control weeds, insect pests and diseases to enhance and sustain productivity in agriculture. This led to indiscriminate use of pesticides causing severe pollution to air, water, food and fiber. Integrated pest management (IPM) is the use of combinations of several alternative pest control measures to keep the pests under the economic threshold level. The United States Department of Agriculture has promoted the use of integrated pest management for the past three decades with a goal to …

Gender Differences In The Impact Of Perceived Social Support On The Relation Between Disability And Depressive Symptoms, Merideth Smith

Graduate Theses, Dissertations, and Problem Reports (ETD)

Older adults with functional disabilities are at an increased risk for experiencing depressive symptoms. Studies using cross-sectional analyses have reported that social support mediates the relation between depressive symptoms and functional disability in older adults. Nonetheless, few studies have investigated this model over time. Additionally, the role of gender in this mediation relation has not been explored. This study used latent growth curve modeling to investigate the potential mediating role of perceived social support within the relationship between disability and depression and whether gender moderates that relation. Twins (n = 656) and co-twins (n = 678) from the Swedish Adoption/Twin …

Synthesis Of Semiconductor Nanoparticles And Characterization Of Physical And Optical Properties, Mikala Shremshock

Graduate Theses, Dissertations, and Problem Reports (ETD)

Nanoparticles are of great interest to a broad scientific community. Because of quantum effects, nanoscale materials exhibit many unique properties that may be exploited for biomedical, defense, and energy applications. Extensive synthetic effort is described for II-VI semiconductor materials. The materials were morphologically confined to zero- or one-dimensional structures. The nanoparticles discussed herein present similar chemical, optical, and physical properties to previously synthesized materials; however, the processes used to obtain these particles are more environmentally benign and use safer chemicals for the researcher and the laboratory environment. These nanomaterials have been extensively characterized to ascertain high quality optical, morphological, and …

Speech Processing Front-End In Low-Power Hardware, Brandon David Rumberg

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this work is to develop analog integrated circuits to serve as low-power auditory front-ends in signal processing systems. An analog front-end can be used for feature-extraction to reduce the requirements of the digital back-end, or to detect and call attention to compelling characteristics of a signal while the back-end is in sleep mode. Such a front-end should be advantageous for speech recognition, noise suppression, auditory scene analysis, hearing prostheses, biological modeling, or hardware-based event detection.;This work presents a spectral decomposition system, which consists of a bandpass filter bank with sub-band magnitude detection. The bandpass filter is low-power …

Implementation Of Forest Stewardship Plans: Understanding The Extent Of Forestry Practices Applied On Enrolled Properties In West Virginia, Elizabeth K. Tichner

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to understand the extent of forest management that is occurring on private forestlands enrolled in the West Virginia Forest Stewardship Program. To quantify the amount of forest management being applied, 295 telephone interviews were conducted in the Fall of 2005 inquiring participants about ten common forest management practices and extent of their implementation, in terms of acreage or mileage. In addition, this study sought to understand the factors associated with the number of respondents that had implemented practices as well as the amount of forestland on which these practices were applied, including practice recommendation, …

A Daily Process Analysis Of Short -Term Physical Activity Goal Pursuits In Midlife: Changes In Goal Processes, Physical Activity, And Subjective Well -Being, Eric A. Goedereis

Graduate Theses, Dissertations, and Problem Reports (ETD)

The prevalence of obesity in the United States increases with age, with the highest rates corresponding to midlife. Midlife health behaviors may play a contributing role in many of the health problems commonly associated with advanced age. Health psychologists who have embraced a life-span developmental perspective argue that it is important to consider the individual developmental trajectories of health and successful aging. Goal-setting has been shown to account for significant variance in physical activity, which has a variety of health-promoting benefits. In order to investigate individual variability in the daily processes of physical activity goal pursuit within a sample of …

Syntheses Of Fused Pyrroloheterocycles, Isatins, Approach Towards The Indole Fragment Of Nosiheptide And A Base-Mediated Formation Of 3-Hydroxycarbazoles, Sobha Priyadarshini Gorugantula

Graduate Theses, Dissertations, and Problem Reports (ETD)

The nitro group has been and still is one of the few functional groups widely studied in synthetic organic chemistry. The reactivity of the nitro group has had important applications in the syntheses of many complex organic molecules, either through its assistance in the formation of new carbon-carbon bonds or in the formation of carbon-heteroatom bonds. Of late, the nitro group has become an important source of nitrogen in organic molecules, thus spawning the syntheses of a range of nitrogen heterocycles.;This dissertation is one such work, wherein the reactivity of the nitro group has been exploited with respect to the …

Understanding The Expression And Implications Of Deceptive Affectionate Messages, Sean M. Horan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Affectionate messages are important in romantic relationships as they are linked to multiple emotional, physical, and relational benefits (e.g., Floyd, 2006a). When examining affection, it is important to distinguish that feelings of affection and the communication of affection are two unique processes that theorists argue covary. Yet, deception researchers have found that individuals routinely lie to their non-married romantic partners about their feelings (DePaulo & Kasy, 1998; DePaulo, Kashy, Kirkendol, Wyer, & Epstein, 1996). This dissertation, composed of two studies, examined how individuals in non-married romantic relationships communicated deceptive affection and the implications of such messages. Study one used a …