Digital Commons Network^™

Multifunctional Reactive Nanocomposite Materials, Demitrios Stamatis

Dissertations

Many multifunctional nanocomposite materials have been developed for use in propellants, explosives, pyrotechnics, and reactive structures. These materials exhibit high reaction rates due to their developed reaction interfacial area. Two applications addressed in this work include nanocomposite powders prepared by arrested reactive milling (ARM) for burn rate modifiers and reactive structures. In burn rate modifiers, addition of reactive nanocomposite powders to aluminized propellants increases the burn rate of aluminum and thus the overall reaction rate of an energetic formulation. Replacing only a small fraction of aluminum by 8Al•MoO₃ and 2B•Ti nanocomposite powders enhances the reaction rate with little change …

Understanding The Origin And Rapid Diversification Of The Genus Anthurium Schott (Araceae), Integrating Molecular Phylogenetics, Morphology And Fossils, Monica Maria Carlsen

Dissertations

Anthurium is a strictly neotropical genus of Araceae ranging from southern Mexico to northern Argentina, including ca. 900 species and displaying an enormous variation in leaf morphology, growth habit, leaf venation pattern and inflorescence and fruit colors. Despite its immense diversity, its ecological importance in Neotropical forests, and a very long history of botanical collection, cultivation, and taxonomical research, Anthurium had been almost neglected in molecular phylogenies. This study combines chloroplast (trnG intron, trnH-psbA and trnC-ycf6 intergenic spacers) and nuclear (CHS first intron) DNA sequence data for 102 Anthurium species and uses maximum parsimony, likelihood and Bayesian phylogenetic analysis to …

Synthesis Of (±)-Cyclophostin, (±)-Cyclipostin P, Their Phosphonate Analogs And New Chemistry Of Vinyl Phosphonates, Raj Kumar Malla

Dissertations

This work is divided into 2 parts: a) total synthesis of (±)-cyclophostin, (±)-cyclipostin P and their monocyclic analogs b) development of a metathesis based methodology for transformation of vinyl phosphonates. Cyclophostin (1) and cyclipostins (2) are bioactive natural bicyclic organophosphates. Cyclophostin is a powerful inhibitor of acetyl cholinesterase (AChE), whereas members of the cyclipostins are potent inhibitors of hormone sensitive lipase (HSL). Cyclophostin (1) and cyclipostin (2) have the same structural core unit, but different phosphate ester substituents. While cyclophostin is a methyl ester, the members of the cyclipostins are phosphate esters of different alkyl groups of various length and …

The Impact Of Rap Music On Audience Values Structure, Janet Mignon Kucia

Dissertations

Music has long been an integral part of culture. Identity and leisure are but two of the myriad reasons cited for music consumption. Rap music is a relatively new genre of music that has enjoyed tremendous success as a commercial and underground movement. This particular genre has become an important part of musical culture and has recently become an area of interest from an academic perspective. In this project, research in the areas of media effects and values formation is explored. Additionally, lyrical content, usage and technological implications are discussed. The author reports on original research in which the correlation …

Does The Biofuel Industry, With The Aid Of Certification Programs, Contribute To Sustainable Development?, James Michael Kierulff

Dissertations

Despite being a source of alternative energy and an avenue for broad economic development, a number of biofuel producers have demonstrated that the biofuel industry has significant potential for unleashing social, environmental and economic harm. To largely avoid such perils, the industry must demonstrate that it is operating in a sustainable manner, contributing to the sustainable development of all stakeholders who rely upon the industry‘s responsible operation. Recently minted, internationally developed certification programs have been developed to move the industry into sustainable compliance and to offer a means by which stakeholders can incentivize the industry toward greater levels of sustainability …

Identification And Analysis Of Proteins And Genes Responsible For Microbial Anaerobic Nitrate-Dependent Iron Oxidation And Overexpression In E. Coli Of Perchlorate Reductase, Ming Gao

Dissertations

SECTION 1 Iron is the fourth most abundant element on the earth crust as well as an essential nutrient for all living organisms. The cycling of iron between the environment and biological systems and the microbial-mediated transformation between Fe2+ and Fe3+ has a significant impact on the biogeochemistry of the environment. The recently discovered microbially-mediated anaerobic nitrate-dependent oxidation of Fe2+ has been shown to play an important role in global iron biogeochemical cycling. Furthermore, the formation of iron oxide from anaerobic nitrate-dependent Fe2+ oxidation results in the adsorption and precipitation of soluble toxic heavy metals and radionuclides from surrounding environment. …

White Americans' Affect Toward African Americans: Predictive Power On Political Behavior And Measurement Problems, Paul Gerard Gottemoller

Dissertations

The purpose of this study is to investigate the impact white affect toward African Americans has on whites' racial policy opinions. The study also identifies the difficulty of measuring affect in the traditional feeling thermometer. Moreover, the study introduces and tests a new method for measuring affect that improves interpersonal comparability of reported affect by anchoring the respondents' self-placements. The study investigates the changes in the relationship between white affect toward African Americans and racial policy opinions of presidential election years between 1964 and 2008. Furthermore, the study tests a new method for measuring affect by having respondents rate where …

A Som+ Diagnostic System For Network Intrusion Detection, Chester Louis Langin

Dissertations

This research created a new theoretical Soft Computing (SC) hybridized network intrusion detection diagnostic system including complex hybridization of a 3D full color Self-Organizing Map (SOM), Artificial Immune System Danger Theory (AISDT), and a Fuzzy Inference System (FIS). This SOM+ diagnostic archetype includes newly defined intrusion types to facilitate diagnostic analysis, a descriptive computational model, and an Invisible Mobile Network Bridge (IMNB) to collect data, while maintaining compatibility with traditional packet analysis. This system is modular, multitaskable, scalable, intuitive, adaptable to quickly changing scenarios, and uses relatively few resources.

An Examination Of Educators' Perceptions Of The School's Role In The Prevention Of Childhood Obesity, Sharon Harris Johnson

Dissertations

Childhood obesity is a prevalent subject of research currently, and many researchers have studied the effectiveness of school programs in battling obesity among students. This case study, utilizing ethnographic tools of observation, interviews, and investigation of artifacts, examines educators' perceptions of the role of the school in the prevention of this epidemic, how perceptions affect practices, and the barriers to prevention efforts. The lens of caring theory, social justice, and critical theory frame the analysis of how educators in a medium-sized elementary school contend with the problem of childhood obesity. Educators in this setting perceived their role in the prevention …

Investigating Nitrate-Dependent Humic Substance Oxidation And In-Service K-12 Teachers' Understanding Of Microbiology, Nastassia N. Jones

Dissertations

Humic substances (HS) are the humified portions of totally decomposed soil organic matter that are ubiquitous in nature. Although these substances have been studied for more than 200 years, neither their metabolic capabilities nor a specific chemical structure has yet to be determined. HS have been studied as a carbon source in many environments where they are degraded; however, previous studies have shown that some microorganisms are capable of utilizing humic substances as electron acceptors and electron donors in anaerobic respiration. Even though there have been humic-reducing and humic-oxidizing microorganisms isolated and studied in recent years, the mechanism of humics …

The Evolution And Development Of Wing Form, Body Size And Flight In Large- And Small-Bodied Fruit Bats (Artibeus Jamaicensis And Carollia Perspiciillata), Jason B. Shaw

Dissertations

Differences in developmental patterns important to diversification are produced through heritable variation of the onset/offset and timing of juvenile growth. As the size and shape of an organism changes during ontogeny, morphological, and behavioral components must adjust to accommodate proper function. This study explored the ontogenetic pathways of two closely related Phyllostomids differing in flight ability, body size, life history strategies, and developmental state at birth. We hypothesized that Artibeus jamaicensis and Carollia perspicillata will show ontogenetic differences that account for the diversification of morphological, body size, and behavioral patterns. Comparisons between the two species‟ flight development, growth rates, and …

A Moderational Model Investigating Child Temperament, Executive Functioning, And Contextual Predictors Of Externalizing Behaviors In Preschoolers, Ferne Arlene Pinard

Dissertations

Child externalizing behavioral problems (e.g., ADHD symptoms and aggressive behaviors) often appear early in life, are relatively stable, and are associated with maladaptive outcomes in many domains of functioning. Research has shown that, for a subset of children who demonstrate these early behavioral patterns, the course is often more pervasive and persistent. Consequently, a better understanding of externalizing behavioral problems during the preschool period is essential. The current study examined whether biologically-based correlates (i.e., child temperament and executive functioning/neurocognitive attention; EF/Attention) would moderate the relation between the contextual correlates (i.e., socioeconomic status and parenting practices) and externalizing behaviors (i.e., ADHD …

Is There A Relationship Between Positive Behavior Supports And Student Achievement?, Todd Edward Boucher

Dissertations

The purpose of this study was to determine whether a relationship exists between a school’s behavior program and student achievement. This study explored the many facets of school behavior plans from across the state of Mississippi and compared the responses of high school principals to the schools’ U.S. history standardized test scores.

School discipline has become an issue that schools find themselves dealing with on a daily basis. While school discipline issues are not new to the educational arena, the way in which some schools are handling them is changing. Some of the changes are as a result of changes …

Dissolved And Colloidal Element Transport Through The Coastal Transition Zone, Moo Joon Shim

Dissertations

There are several factors (e.g., hurricanes, floodplain, and anthropogenic sources) that could modify trace element behavior through the coastal transition zone (CTZ). However, there is still a lack of information about these variables in affecting trace elements in the CTZ. For this study, water samples were collected in the Pearl River (PR), Bay of St. Louis (BSL), and the Mississippi River plume to study the effects of these factors on trace element.

A possible effect of Hurricane Katrina on water quality was examined in the East Pearl River (EPR). Hurricane Katrina could have resulted in increased inputs of organic matter …

Latent Growth Modeling Of A Nutrition And Physical Activity Intervention, Alicia Dea Sample

Dissertations

The health, economic, and social impacts of physical inactivity and unhealthy dietary patterns are quite significant and evidenced by the fact that only 3-4% of American adults follow all the dietary advice recommended by the Dietary Guidelines for Americans (DGA; Kohatsu, Robinson, & Torner, 2004), and specific subpopulations, including the rural South, are affected even more drastically (McCabe-Sellers et al., 2007). Furthermore, the majority of the people in the United States do not currently meet recommended amounts of physical activity (PA) and have not since the mid 1980s (U.S. Department of Health and Human Services [USDHHS], 2008). To address the …

Self-Repairable Polymeric Networks: Synthesis And Network Design, Biswajit Ghosh

Dissertations

This dissertation describes the design, synthesis and development of a new class of polymeric networks that exhibit self-repairing properties under UV exposure. It consists of two parts: (a) modification and synthesis of oxetane (OXE), and oxolane (OXO) substituted chitosan (CHI) macromonomer, and (b) design, and synthesis of self-repairing polyurethane (PUR) networks consisting of modified chitosan. Unmodified CHI consisting of acetamide (-NHCOCH₃), primary hydroxyl (-OH), and amine (-NH₂) functional groups were reacted with OXE or OXO compounds under basic conditions in order to substitute the 1° –OH groups, and at the same time, convert -NHCOCH₃ functionalities …

The Relations Among Laterality, Cortisol, And Approach-Avoidance Behavior In Garnett's Bushbaby (Otolemur Garnettii), David Burton Hanbury

Dissertations

Many studies to date have demonstrated that approach and avoidance behaviors are processed asymmetrically in the brain and may be reflected in measures such as handedness. The purpose of this study was to extend work in primates on this topic to Garnett’s bushbaby, a prosimian species. Furthermore, to determine whether measures in addition to handedness relate to approach-avoidance behavior, lateralized differences in tympanic membrane temperature were assessed. Cortisol measures were also obtained to determine whether it was related approach-avoidance behavior and handedness. Eleven captive-born Garnett’s bushbabies (Otolemur garnettii) were evaluated for handedness and responsiveness to novelty. Moreover, the …

Precision Synthesis Of Functional Materials Via Raft Polymerization And Click-Type Chemical Reactions, Joel Diez Flores

Dissertations

The need to tailor polymeric architectures with specific physico-chemical properties via the simplest, cleanest, and most efficient synthetic route possible has become the ultimate goal in polymer synthesis. Recent progress in macromolecular science, such as the discoveries of controlled/“living” free radical polymerization (CRP) methods, has brought about synthetic capabilities to prepare (co)polymers with advanced topologies, predetermined molecular weights, narrow molecular weight distributions, and precisely located functional groups. In addition, the establishment of click chemistry has redefined the selected few highly efficient chemical reactions that become highly useful in post-polymerization modification strategies. Hence, the ability to make well-defined topologies afforded by …

An Electrophysiological Investigation Of The Cognitive Processes Underlying Provoked Aggression In Humans, Jennifer Renee Fanning

Dissertations

Recently, the event-related potential (ERP) technique has been applied to questions of social information processing. Several studies have examined standard and social information processing variables in aggressive individuals, but little is known about the neurophysiological processes that take place in real-time during an aggressive encounter. In this study, 48 men and women high and low in aggression history exchanged noise blasts of varying intensity with a (fictitious) opponent in a modified version of a well-validated laboratory-controlled behavioral measure of aggression, the Taylor Reaction-time Task (Taylor, 1967), while ERPs were simultaneously being recorded at scalp sites. Mixed model ANOVAs were used …

Circadian Rhythm And Vigorous Activity: Do They Make A Difference In Executive Function?, Janie Sue Ryland

Dissertations

PL 107-110, the No Child Left Behind Act of 2001, a federally mandated accountability system based on standards, attendance, and dropout rates has forced educational leaders to explore new avenues of student improvement. Research suggests that all three factors are impacted by scheduling preferences that are relative to time of day. The aim of this study was to extend evidence of executive function as it is impacted by time of day and diurnal preference when exposed to vigorous exercise conditions. Data were collected from a sample that included 100 sixth graders (60 females and 40 males) during the spring semester …

The Relationship Between Response To Intervention Implementation And Student Achievement, Carla Moran Mccaleb

Dissertations

The purpose of this study was to determine if there was a relationship between Response to Intervention (RTI) implementation and student achievement in reading. The study used primary data derived from the winter STAR reading diagnostic screener collected from third, fourth and fifth grade students in the RTI process. These scores were then compared to the archival data collected in the fall STAR reading diagnostic screener from the same students.

Paired-tests were performed in order to determine if there was a relationship between RTI implementation and student achievement in reading. The study sample represented in this investigation was 125 students …

The Impact Of Shrimp Farming On Mangrove Ecosystems And Local Livelihoods Along The Pacific Coast Of Ecuador, Stuart Edward Hamilton

Dissertations

This manuscript examines the expansion of Ecuador’s shrimp aquaculture industry since 1970 and the implications of this expansion on coastal residents’ food security and livelihood options. Shrimp aquaculture expanded from essentially nothing in 1970; to account for 26% of all Ecuadorian private exports by 1998. The rapid expansion of shrimp aquaculture in Ecuador’s estuaries has caused a fundamental shift in livelihoods among those who live and work in the immediate vicinity of the newly created shrimp farms. This research not only details the important land use change that has occurred within Ecuador’s estuaries during the transition from mangrove estuary to …

The Black Plumb Line: Re-Evaluating Race And Africanist Images In Non-Black Authored American Texts, Lashondra Vanessa Robinson

Dissertations

This study evaluates Africanisms (representations of racialized or ethnicized blackness) within three contemporary non-black authors’ texts: Jewish American Saul Bellow’s novel Henderson the Rain King, white southerner Melinda Haynes’ novel Mother of Pearl, and Nyurican poet Victor Hernández Cruz’s works “Mesa Blanca” and “White Table.” Though not entirely unproblematic, each selection somehow redefines black identity and agency to challenge denigrated representations of Africanist people and culture. In the process, each author subverts faulty components of American myths of racial purity, particularly stratifying black-white dualisms that promote whiteness, racial supremacy, and resulting undue privilege. This study also traces how Bellow, Haynes …

An Analysis Of Fringed Myotis (Myotis Thysanodes), With A Focus On Colorado Distribution, Maternity Roost Selection, And Preliminary Modeling Of Population Dynamics, Mark Andrew Hayes

Dissertations

The purpose of my research was to describe the distribution and roosting ecology of Myotis thysanodes in Colorado, and to initiate preliminary population dynamics modeling of the potential impacts of a changing climate on forest dwelling Myotis in the Southern Rocky Mountains. Seven hundred and twenty-nine Colorado capture and occurrence records of M. thysanodes were documented. I used 546 M. thysanodes records that included information about sex and reproductive status in an analysis of variance comparing elevational distribution among sex and reproductive classes. There were significant differences among reproductive classes, but not between sex classes. Sixteen actual or probable M. …

Experimental Infection Of Jamaican Fruit Bats (Artibeus Jamaicensis) With Tacaribe Virus, Ann C. Hawkinson

Dissertations

No abstract provided.

Evaluating The Role Of Perceived Access To Support And School Safety In Adolescent Exposure To Trauma: A Mixed Methods Study, Amanda H. Stoeckel

Dissertations

This mixed methods study evaluated lifetime trauma exposure, protective factors, and current psychological functioning among 78 adolescents from two public middle schools in rural and suburban communities. One hundred percent of adolescents reported experiencing at least one traumatic event at some point during their lives. After controlling for gender, ethnicity, socioeconomic status, and special education/general education placement, more trauma exposure was associated with more post-traumatic stress and depressive symptoms, more teacher-rated externalizing behaviors, and lower teacher-rated adaptive functioning. Perceived access to support and factors of school safety demonstrated protective effects in the relationship between trauma exposure and domains of psychological …

The Effect Of Exercise On Cardiac Function And Doxorubicin Accumulation In Left Ventricular Tissue Of Rats, Brock Thomas Jensen

Dissertations

Doxorubicin (DOX) is an anthracycline antibiotic that has cytotoxic actions. The therapeutic use of DOX to treat a wide array of cancers is limited by a dose-dependent cardiotoxicity. Although DOX is known to have several adverse side-effects, acute and chronic cardiotoxicity have received the most attention as both may eventually lead to heart failure. While exercise has been shown to protect against DOX cardiotoxicity, a clear and consistent mechanism to explain its cardioprotective effects is lacking. High performance liquid chromatography (HPLC) is a valuable instrument that can be used to evaluate cardiac DOX accumulation. We hypothesized that a reduction in …

Power Dynamics And Questioning In Elementary Science Lessons, Lori Ann Reinsvold

Dissertations

Discourse interactions between a teacher and students in an inquiry-based fourth-grade science classroom were analyzed to investigate how power dynamics and questioning strategies within elementary science lessons help support students in building their science understanding. Five inquiry-based classroom sessions were observed; verbal interactions were audio- and video-recorded. Research data consisted of observation transcripts, teacher interviews, student work, and instructional materials. Analyses were conducted on the frequencies of utterances, participation roles, power categories, and questioning categories. Results revealed that when students used more frequent power, (a) no significant differences were noted between frequencies of teacher and student talk, (b) the teacher …

Qualitative Study: People With Disabilities And Internal Barriers To Work, Patricia Ann Yeager

Dissertations

A great deal of work has been done over the past 40 years to make the built environment more accessible. Public awareness activities have been conducted to begin to change society's attitudes toward people with disabilities. Changes in government benefits now allow individuals to retain benefits while working. However, people with disabilities are still woefully unemployed. This study examined internal barriers to work that some people with disabilities on government benefits may experience. Using qualitative methods, the researcher uncovered internal barriers to work among people with disabilities on government disability benefits. Data were collected through telephone interviews with six individuals …

Transformation Of Arabidopsis Thaliana With Heat Stress-Related Genes From A Copaifera Officinalis Expressed Sequence Tag Library, Samuel R. Zwenger

Dissertations

This dissertation has three components: (1) discovery of genes involved in heat stress-related processes derived from a tropical plant known as the diesel tree (C. officinalis) by means of an expressed sequence tag (EST) library, (2) stable transformation of Arabidopsis thaliana with C. officinalis heat stress-related genes and (3) assessing the degree to which C. officinalis heat-stress associated genes provide thermotolerance in transgenic A. thaliana. This dissertation project has important plant biotechnological components as well as agriculturally important themes. Global climate change is predicted to result in elevated temperatures over the next century and so studying the influence of heat …