Digital Commons Network^™

Laser Induced Breakdown Spectroscopy For Detection Of Organic Residues Impact Of Ambient Atmosphere And Laser Parameters, Christopher G. Brown

Electronic Theses and Dissertations

Laser Induced Breakdown Spectroscopy (LIBS) is showing great potential as an atomic analytical technique. With its ability to rapidly analyze all forms of matter, with little-to-no sample preparation, LIBS has many advantages over conventional atomic emission spectroscopy techniques. With the maturation of the technologies that make LIBS possible, there has been a growing movement to implement LIBS in portable analyzers for field applications. In particular, LIBS has long been considered the front-runner in the drive for stand-off detection of trace deposits of explosives. Thus there is a need for a better understanding of the relevant processes that are responsible for …

The Effects Of Age On Reproduction In A Citrus Root Weevil Diaprepes Abbreviatus, Heather R. Chasez

Electronic Theses and Dissertations

Understanding the factors influencing mate choice is a major focus of sexual selection. Many factors are potentially involved, including age of the individual. The good genes model and the youth advantage model both make predictions about the effect of age on mate choice. Under the good genes model older mates would be the more preferable due to their proven high survivability. The “youth advantage” model, predicts that young to intermediate age males would be more advantageous as mates because of a decrease in sperm quality and the possibility of increased germ-line mutations in older animals. I examined the effects of …

Glial Differentiation Of Human Umbilical Stem Cells In 2d And 3d Environments, Hedvika Davis

Electronic Theses and Dissertations

During differentiation stem cells are exposed to a range of microenvironmental chemical and physical cues. In this study, human multipotent progenitor cells (hMLPCs) were differentiated from umbilical cord into oligodendrocytes and astrocytes. Chemical cues were represented by a novel defined differentiation medium containing the neurotransmitter norepinephrine (NE). In traditional 2 dimensional (2D) conditions, the hMLPCs differentiated into oligodendrocyte precursors, but did not progress further. However, in a constructed 3 dimensional (3D) environment, the hMLPCs differentiated into committed oligodendrocytes that expressed MBP. When co-cultured with rat embryonic hippocampal neurons (EHNs), hMLPCs developed in astrocytes or oligodendrocytes, based on presence of growth …

The Origins Of Lactase Persistence And Ongoing Convergent Evolution, Beth A. Keller

Electronic Theses and Dissertations

As a primary factor in human evolution, natural selection is an important component of genetic research. Studies of lactase persistence suggest that positive selection has played a powerful role in the adaptation to a lifelong consumption of fresh milk. Using multiple research studies of lactase persistence and suspected corresponding single nucleotide genetic polymorphisms, this study combines data sources to determine whether evidence exists for natural selection of a specific cytosine-to-thymine genetic mutation located 13,910 base pairs (T-13910) upstream from the lactase gene. This polymorphism has potential to be a causal element for lactase persistence, and data suggest that natural selection …

The Portrayal Of Teen Pregnancy In The Tv Series "The Secret Life Of The American Teenager", Erin Lovell

Electronic Theses and Dissertations

The aim of the current study was to investigate the way teen pregnancy is portrayed in Seasons 1 and 2 of the television drama The Secret Life of the American Teenager. Framing theory and social cognitive theory were used as guiding frameworks for exploring the way the main character’s pregnancy was presented and the way this presentation may influence the ideas and behaviors of viewers. A qualitative content analysis was conducted to examine portrayals in the first 23 episodes. Results indicated that teen pregnancy was portrayed in five major ways: as Dramatic, as Identity, as Manageable, as Transformative, and as …

The Effectiveness Of Teaching Methods Designed To Improve Student Engagement And Retention Of Physics Subject Matter For Both Science And Non-Science Majors, Dan Maronde

Electronic Theses and Dissertations

The necessity of students’ engagement with the subject matter for successful learning is welldocumented in education research in general, and in physics education research in particular. This study examines the merits of two different programs designed to improve student learning through enhanced student engagement with the material. The target populations of the two programs are different: One is the group of students taking a physical science class as part of the general curriculum required of non-science, non-engineering majors; the other is the group of students, mostly in engineering disciplines, who must take the calculus-based introductory physics sequence as part of …

Understanding The Invasion Of Florida's Intertidal Crassostrea Virginica Reefs By Non-Native Marine Invertebrate Species, Ethan Fletcher Nash

Electronic Theses and Dissertations

Predicting the locations of new biological invasions has become a high priority for biologists as well as trying to predict if newly introduced species will become damaging to native ecosystems. Reefs of the eastern oyster Crassostrea virginica in Mosquito Lagoon, Florida have been highly disturbed in recent years resulting in dead reefs (piles of dead, disarticulated shells) some of which have been restored. I conducted oyster reef surveys for non-native invertebrates to determine if disturbance on these oyster reefs might assist invasion by two species, Mytella charruana and Perna viridis, recently introduced to the southeastern coast of the United States. …

Encountering Questions Of Religion In Psychotherapy: A Hermeneutical-Phenomenological Study Of Religious Patients' Experiences, Jonathan Ahern

Electronic Theses and Dissertations

This dissertation presents a hermeneutical-phenomenological investigation of having one's religious or spiritual views called into question in psychotherapy. A review of the literature revealed very few studies exploring the experiences of religious or spiritually devoted psychotherapy patients and a complete lack of studies describing the lived phenomenon of having one's religious or spiritual views called into question in psychotherapy. Three self-described "religious" or "spiritually devoted" former psychotherapy patients provided in-depth descriptions of having their religious views or practices called into question in psychotherapy. Participants' descriptions--gathered first in writing and then by way of a hermeneutic interview--comprised the empirical qualitative data …

Nitrate Metabolism In The Epsilonproteobacteria: Campylobacter Jejuni And Sulfurospirillum Barnesii, Courtney Sparacino-Watkins

Electronic Theses and Dissertations

In this study the nitrate metabolism of Campylobacter jejuni and Sulfurospirillum barnesii will be examined, specifically the periplasmic nitrate reductase (Nap) enzyme which is transforms of nitrate to nitrite. The catalytic subunit, NapA, is a molybdenum dependent enzyme. Isolation of molybdenum containing enzymes is not straightforward as co-factor can be lost during protein purification procedures. This study used two protein purification methods to isolate NapA. First, NapA was isolated directly from S. barnesii using protein fractionation and anion exchange chromatography. Second, molecular cloning was used to express the recombinant affinity-tagged S.barnesii and C. jejuni NapA proteins from E. coli. Immobilized …

Living With Schizophrenia: A Phenomenological Investigation, Andri Yennari

Electronic Theses and Dissertations

This study investigated the experience of living with schizophrenia through seven participants' accounts of the way they have been perceived and treated by others, as well as the way they viewed themselves after having been identified with the diagnosis of schizophrenia. Participants were recruited through psychologists at the mental health facility where they received treatment and were interviewed by the researcher in that facility.

To analyze the data of this study, an empirical phenomenological method was used to explicate the meaning of schizophrenia as it was experienced and lived by participants. A hermeneutic component was included to interpret the data …

Studies On The Preparation And Luminescence Properties Of Cadmium Selenide Quantum Dots, Their Immobilization, And Applications., Travis Justin Heath

Electronic Theses and Dissertations

Quantum dots are semiconductive particles whose properties are highly influenced by the presence of at least one electron. Cadmium selenide quantum dots were synthesized via colloidal synthesis. Contrary to previous preparations, more focus was placed on the temperature rather than the duration of time at which they form. A series of colored solutions were obtained because the excited quantum dots of various sizes emitted specific wavelengths of light. The emission spectra showed that the temperature-dependent quantum dots were successfully synthesized. The quantum dots were also immobilized on various surfaces, and the luminescence properties were examined. The quantum dots that were …

Perceptions Of Maternal Stress And Neonatal Patient Outcomes In A Single Private Room Versus Open Room Neonatal Intensive Care Unit Environment., Lisa M. Smithgall

Electronic Theses and Dissertations

Limited clinical evidence exists regarding whether the single private room Neonatal Intensive Care Unit (NICU) environment of care delivery has a positive, negative, or neutral impact on health outcomes for the high risk neonate and on maternal stress as compared to the open room design. The study purpose was to examine whether a difference exists in health outcomes in the open room versus single private room NICU environment. The factors considered were weight gain, ventilator days, hospital length of stay, incidence and grade of intraventricular hemorrhage (IVH), the number of parental visits, and perceptions of maternal stress. Infants hospitalized in …

An Analysis Of Monitoring The Future: A Look At The Relationship Between Juvenile Delinquency And Involvement In School., Thomas Theodore Zawisza

Electronic Theses and Dissertations

The purpose of this study was to examine the relationship between juvenile delinquency and involvement with various school activities. In order to do so data from the Monitoring the Future survey of high school seniors in 2008 were used. Univariate measures included descriptive statistics of the variables, while bivariate analysis determined if a relationship exists between the dependent and independent variables. Results of the analysis suggested mixed support for the relationship between adolescent delinquency and involvement in school activities.

Conjugate Additions And Transposition Of The Allylic Alcohols Of Enol Ethers Of 1, 2-Cyclohexanedione., Barnabas Otoo

Electronic Theses and Dissertations

A variety of protected enolic forms of 1, 2-cyclohexanedione was prepared as substrates for conjugate addition studies using organocopper reagents. The sequence involved the enol ether preparation via the enolate, alkylation with an organometalic reagent, and oxidative rearrangement with pyridinium chlorochromate followed by the conjugate addition reactions. Protection of 1, 2-cyclohexanedione was achieved by reacting with chloro tert-butyldimethyl silane and subjected to alkylation. Steric problems were encountered and so an alternative protective group the methoxymethyl acetal was prepared and studied. Alkylation of these derivatives was successful; however, the oxidation was problematic and although evidence for rearrangement was observed in one …

A Study Of The Effects Of The Length Of Student-Teaching Experiences On New Teacher Efficacy., Alan Wayne Addison

Electronic Theses and Dissertations

This study explores the relationship between the length of student-teaching experiences and new teacher efficacy. Each year thousands of prospective new teachers endure the interview processes to be hired, complete induction programs, and begin their careers only to determine that the teaching profession is not what they assumed it would be. Local school districts spend thousands of dollars each year on orientation for these new teachers only to find them resigning within the first 5 years of service. Increasing new teacher efficacy is imperative to reducing new teacher attrition rates. The more student-teaching experiences an individual collects before entering the …

Neurochemical Levels Correlate With Population Level Differences In Social Structure And Individual Behavior In The Polyphenic Spider, Anelosimus Studiosus., Jennifer Bryson Price

Electronic Theses and Dissertations

Anelosimus studiosus is a socially polyphenic spider. Individuals can be classified as social/tolerant or solitary/aggressive. These behavioral differences are associated with considerable variation in social structure. Here, we begin to examine the physiological differences that may underlie the behavioral dimorphism in this species and possible implications for the evolution of sociality. Octopamine is a neurotransmitter that has been found to elevate aggression in invertebrates. Serotonin has been shown, in some cases, to interact antagonistically with octopamine. We used High Pressure Liquid Chromatography with Electrochemical Detection to quantify levels of these neurochemicals among adult females from social (multi-female) and solitary (single-female) …

Molecular Evidence Suggests Multiple Evolutionary Origins Of Sociality In The Polyphenic Spider Anelosimus Studiosus (Araneae: Theridiidae)., Nathaniel O. Weber

Electronic Theses and Dissertations

Anelosimus studiosus exhibits two behavioral phenotypes: subsocial and social. This is the only documented spider inhabiting a temperate climate exhibiting social behavior. While the subsocial phenotype is most common throughout the range, the social behavior occurs in isolated pockets in northern latitudes. This study examines the origins of the social phenotype within a segment of the spider's range. Two hypotheses are tested: 1) pockets of social behavior represent a single origin or 2) pockets of social behavior represent local evolutions, thus leading to multiple origins of evolution. Microsatellite loci were used to determine genetic structure of the population and to …

Mosaic Analysis With Double Markers (Madm) As A Method To Map Cell Fates In Adult Mouse Taste Buds., Preston D. Moore

Electronic Theses and Dissertations

Taste buds are chemosensory endorgans embedded in the oral epithelium composed of cells that undergo continuous replacement. Mature taste cells live on average 10-14 days and are replaced by new cells when they die. However, the mechanism by which taste cells are produced and integrated into the taste bud as mature taste cells remains unknown. Previous studies approached this issue from either cell cycle gene expression properties or lineage tracing of precursor cells. In our study, we apply a new fate mapping technique that combines these two ideas. This technique, Mosaic Analysis with Double Markers, allows for simultaneous gene knockout …

Wrongful Convictions As A Result Of Public Defender Representation., Annie Elizabeth Ross

Electronic Theses and Dissertations

Our criminal justice system works very hard to prevent criminals from harming other individuals; however, unfortunately mistakes happen. One wrongful conviction is one too many. There are multiple factors that can be assumed to be the cause of wrongful convictions. However, due to the lack of directly related research, the determents are not well established. The following research addresses wrongful convictions as a result of public defender representation. Through the process of theory construction, the research uses critical race theory and social disorganization theory to show the relationship between court appointed representation and wrongful convictions. A new theory is also …

Fatherhood And Fatherland In Chimamanda Adichie's "Purple Hibiscus"., Audrey D. Peters

Electronic Theses and Dissertations

Purple Hibiscus, a novel by third-generation Nigerian author Chimamanda Adichie, appears at first glance to be a simple work of adolescent fiction, a bildungsroman in which a pair of siblings navigate the typical challenges of incipient adulthood: social ostracism, an abusive parent, emerging desire. However, the novel's setting-a revolutionary-era Nigeria-is clearly intended to evoke post-Biafra Nigeria, itself the setting of Adichie's other major work, Half of a Yellow Sun. This setting takes Purple Hibiscus beyond the scope of most modern adolescent fiction, creating a complex allegory in which the emergence of self and struggle for identity of the …

The Effect Of Sternocleidomastoid Muscle Activation Pattern And Feedback Condition On The Vestibular Evoked Myogenic Potential., Mary Jo Davenport

Electronic Theses and Dissertations

The vestibular evoked myogenic potential (VEMP) has been shown to be clinically useful in providing diagnostic information regarding the function of the otolith receptors, inferior vestibular nerve, and vestibulospinal pathways. The VEMP is a biphasic response elicited by loud clicks or tone bursts and recorded from the tonically contracted sternocleidomastoid (SCM) muscle. Because the VEMP is an inhibitory response, it is important to investigate stimulus and parameter characteristics in order to determine the optimal test protocol and maximize clinical usefulness. The aims of this study were 1) to evaluate the effects of 4 different methods of SCM muscle activation and …

Discovery And Characterization Of An Antibiotic From The Soil Bacterium Bacillus Sp., Thomas S. Barber

Electronic Theses and Dissertations

Many important antibiotics have become nearly obsolete due to the rise of antibiotic resistant pathogens. Rhodococcus, an actinomycete related to the prolific antibiotic producing genus Streptomyces, harbors over 30 genes for secondary metabolism that could be involved in antibiotic production. Several antibiotics have already been reported for Rhodococcus, suggesting the genus may be a good source for new inhibitory compounds. Fifty four soil bacteria were isolated using enrichment culture techniques (including 37 Rhodococcus) and screened for antibiotic producers. BTHX2, a species of Bacillus was found to have activity against Micrococcus luteus and Rhodococcus erythropolis. BTHX2 …

The Correlation Of The Concentration Of Selected Metals Determined In Water And Fish Samples From A Public Pond., Paula Kay Edwards

Electronic Theses and Dissertations

The concentrations of heavy metals (Cd, Cu, Fe, Ni, Pb, Zn) were measured in water, and fish samples caught from the pond at Fishery Park in Unicoi County, TN. The water samples were collected once a week for 8 weeks. The amounts of metals in the muscle tissues, gill, and liver of the two fish species were measured. This was to determine if any correlation exists between the metal contents in water and those in the fish samples. The concentration ranges for the heavy metals found in the water samples are as follows: Zn 0.04-0.13; Cu, 0.00-0.00; Pb, 0.00-0.59; Cd, …

The Sir Model When S(T) Is A Multi-Exponential Function., Teshome Mogessie Balkew

Electronic Theses and Dissertations

The SIR can be expressed either as a system of nonlinear ordinary differential equations or as a nonlinear Volterra integral equation. In general, neither of these can be solved in closed form. In this thesis, it is shown that if we assume S(t) is a finite multi-exponential, i.e. function of the form S(t) = a+ ∑ⁿ_k=1 r_ke^-σ_kt or a logistic function which is an infinite-multi-exponential, i.e. function of the form S(t) = c + a/b+e^wt, then …

Lack Of Rhythmicity In The Honey Bee Queen: An Investigation Of Temporal Behavioral Patterns In Apis Mellifera Ligustica., Jennifer N. Johnson

Electronic Theses and Dissertations

Little is known about the behavioral patterns of honey bee queens. To determine if mated honey bee queens possess diel rhythmicity in behavior, we observed them in glass-sided observation hives using three types of observation regimes: focal studies consisting of 2-hour and 24-hour continuous observations as well as scan-sampling of multiple queens. All behaviors (active: walking, inspecting, egg-laying, begging for food, feeding, and grooming self; inactive: standing) occurred at all times of day and night, but no queen showed consistent diel rhythmicity in any of the individual behaviors. There were no consistent diel differences in active versus inactive behaviors or …

Modulation Of Alpha-Subunit Visit-Dg Sequence Residues Ser-347, Gly-351 And Thr-349 In The Catalytic Sites Of Escherichia Coli Atp Synthase., Laura Elaine Brudecki

Electronic Theses and Dissertations

Binding of inorganic phosphate (P_i) in ATP synthase catalytic sites is a crucial step for the synthesis of adenosine-5'-triphosphate (ATP). ATP is the fundamental means of cellular energy in almost every organism, and in order to gain insight into the regulation of ATP catalysis, critical amino acid residues responsible for binding P_i must be identified. Here, we investigate the role of highly conserved α-subunit VISIT-DG sequence residues αSer-347, αGly-351, and αThr-349 in P_i binding. Mutations αS347A/Q, αG351Q, αT349A/D/R, βR182A, and αT349R/βR182A were generated via site directed mutagenesis. Results from biochemical assays showed that αSer-347 is required …

Topology And Function Of Nyctalopin In Yeast And In-Vitro Translation Systems., Pasano Pasano Bojang

Electronic Theses and Dissertations

Congenital stationary night blindness 1 (CSNBl) is a genetic disorder characterized in humans by night blindness, low visual acuity and myopia. CSNB 1 is caused by defects in genes that are involved in signaling between photoreceptors and depolarizing bipolar cells (DBCs). DBCs utilize a metabotropic glutamate receptor-6 (Grm6) cascade that modulates the activity of a non-specific cation channel. CSNBI is diagnosed by a reduced b-wave in the electroretinogram (ERG). A b-wave indicates that DBCs are depolarized in response to a flash of light. In the dark, there is a tonic release of glutamate from the photoreceptors into the synaptic cleft. …

Features Extraction Using Random Matrix Theory., Viktoria Borisovna Rojkova

Electronic Theses and Dissertations

Representing the complex data in a concise and accurate way is a special stage in data mining methodology. Redundant and noisy data affects generalization power of any classification algorithm, undermines the results of any clustering algorithm and finally encumbers the monitoring of large dynamic systems. This work provides several efficient approaches to all aforementioned sides of the analysis. We established, that notable difference can be made, if the results from the theory of ensembles of random matrices are employed. Particularly important result of our study is a discovered family of methods based on projecting the data set on different subsets …

Testing The Use Of Molluscs To Infer Climate With Special Reference To The Late Cenozoic Molluscs Of The Meade Basin, Southwest Kansas., Brian William Steffen 1975-

Electronic Theses and Dissertations

Twenty-six fossil assemblages of land and freshwater molluscs from the Pliocene to the present, were collected from locations near the town of Meade, Kansas, U.S.A. and were analyzed (along with the extant molluscan fauna of Meade County, Kansas) to look for changes in molluscan diversity through time. The fossil assemblages were analyzed for two reasons: I) to test the hypothesis that diversity (measured as taxonomic richness, dominance, turnover and habitat type) did not change through the five million years of this study (HOI); and 2) to test the hypothesis that there is no relationship between the taxonomic composition of a …

Signal Processing In The Tectothalamic Pathway., Haiyang Wei

Electronic Theses and Dissertations

The pulvinar is the largest nucleus of the human dorsal thalamus and is affected in a variety of brain disorders, such as schizophrenia. The experiments described in this dissertation elucidate key features of tecto-pulvino-cortical pathways as a first step toward understanding their role in coding visual stimuli and coordinating appropriate responsive actions. The tree shrew is used as the animal model because the visual structures of the tree shrew brain display many of the features of the primate brain, and the tectopulvinar pathways are particularly enhanced in this species. The connections formed between the tectorecipient pulvinar nucleus and cortex were …