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Localized Mechanical Deformation And Dissolution Of 45s5 Bioglass, Ding Li

University of Kentucky Doctoral Dissertations

Bioactive glasses react with the human physiological solution in control of their biofunctionality. The stress state in bioactive glasses determines the chemomechanical reaction and their biofunctionality. Using the microindentation technique, the effect of the indentation deformation on the surface damage and material dissolution of 45S5 bioglass was investigated.

The indentation-induced residual stresses were calculated. Complete anelastic recoveries of the indentation depths and the impression marks were observed for the first time, which was likely driven by the stored strain energy over the anelastic deformation zone. The indentation-induced local surface damages were revealed before and after the immersion tests in phosphate …

Analysis Of The Crmp Gene In Drosophila: Determining The Regulatory Role Of Crmp In Signaling And Behavior, Deanna Hardt Morris

University of Kentucky Doctoral Dissertations

The mammalian genome encodes five collapsin response mediator protein (CRMP) isoforms. Cell culture studies have shown that the CRMPs mediate growth cone dynamics and neuron polarity through associations with a variety of signal transduction components and cytoskeletal elements. CRMP is also a member of a protein family including the presumably ancestral dihydropyrimidinase (DHP) protein that catalyzes the second step in pyrimidine degradation. In Drosophila, CRMP and DHP proteins are produced by alternatively spliced transcripts of the CRMP gene. The alternative protein forms have a 91% sequence identity, but unique expression patterns. CRMP is found exclusively in neuronal tissues and …

The Feminization Of Private Investigation: A Sociological Analysis, Jessica Simpson Pearce

LSU Doctoral Dissertations

This dissertation outlines the occupation of private investigation and the role that females play within that profession. The difficulties women experience in male-oriented occupations remains noteworthy in sociological research today. Progress has been made, yet many barriers still exist for women. These include structural, social, and cultural factors that influence women and/or the jobs that they hold. With the completion of interviews with twenty-six female private investigators, I was able to analyze the existing structural, interactional, and gender barriers which moderate the number of women that work as private investigators. Few studies have examined this occupation and this gap may …

Evolution And The End Of A World, David Edward Long

University of Kentucky Doctoral Dissertations

This dissertation examines college student understanding and attitudes toward biological evolution. In ethnographic work, I followed a cohort of 31 students through their required introductory biology class. In interviews, students discuss their life history with the concept - in school, at home, at church, and in their communities. For some Creationist students, confronting evolution in class has meant confronting existential issues regarding both the basis of science and the basis of faith. For other Creationist students, claims of evolution's theoretical strength are eschewed for its direct challenge to their worldview. For most students, science holds minimal interest against other values …

Function Of Androgen Receptor In Prostate Cancer Epithelial Mesenchymal Transition And Microtubule Targeting, Menglei Zhu

University of Kentucky Doctoral Dissertations

Prostate cancer is the most frequently diagnosed non-skin cancer and the third leading cause of cancer mortality among men in the US. Androgens are functionally required for the normal growth of the prostate gland and play a critical role in prostate tumor development and progression. Epithelial-mesenchymal-transition (EMT) is an important process during normal development, and cancer cell metastasis.

This study examined the ability of androgens to influence EMT of prostate cancer epithelial cells and evaluate the effect of taxol chemotherapy on androgen signaling in prostate cancer cells in prostate cancer. The EMT pattern was evaluated on the basis of expression …

Synthesis And Characterization Of Magnetic Hydrogel Nanocomposites For Cancer Therapy Applications, Samantha Ann Meenach

University of Kentucky Doctoral Dissertations

Currently, cancer is the second leading cause of death in the United States. Conventional cancer treatment includes chemotherapy, radiation, and surgical resection, but unfortunately, all of these methods have significant drawbacks. Hyperthermia, the heating of cancerous tissues to between 41 and 45°C, has been shown to improve the efficacy of cancer therapy when used in conjunction with irradiation and/or chemotherapy. In this work, a novel method for remotely administering heat is presented. This method involves heating of tumor tissue using hydrogel nanocomposites containing magnetic nanoparticles which can be remotely heated upon exposure to an external alternating magnetic field (AMF). The …

Improvement Of New Oil Crops For Kentucky, Watchareewan Jamboonsri

University of Kentucky Doctoral Dissertations

Three oil crops, chia (Salvia hispanica L.), flax (Linum usitatissimum L.), and castor (Ricinus communis L.), were studied because of their nutritional and industrial values. Chia and flax are rich in an ω3 fatty acid, α-linolenic acid, and castor is a very high oil producer and high in a hydroxy fatty acid. Ethyl methanesulfonate (EMS) and gamma rays were employed to mutagenize chia seeds to produce early flowering mutants. The M₁ population was grown and induced to flower by short-day photoperiods. The M₂ population was planted in the field in Lexington, KY in 2008. Early …

In Vivo Oxidative Stress In Alzheimer Disease Brain And A Mouse Model Thereof: Effects Of Lipid Asymmetry And The Single Methionine Residue Of Amyloid-Β Peptide, Miranda Lu Bader Lange

University of Kentucky Doctoral Dissertations

Studies presented in this dissertation were conducted to gain more insight into the role of phospholipid asymmetry and amyloid-β (Aβ)-induced oxidative stress in brain of subjects with amnestic mild cognitive impairment (aMCI) and Alzheimer disease (AD). AD is a largely sporadic, age-associated neurodegenerative disorder clinically characterized by the vast, progressive loss of memory and cognition commonly in populations over the age of ~65 years, with the exception of those with familial AD, which develop AD symptoms as early as ~30 years-old. Neuropathologically, both AD and FAD can be characterized by synapse and neuronal cell loss in conjunction with accumulation of …

Edaphic And Vegetative Controls On Mercury Cycling In Oligohaline Wetlands, Jonathan M. Willis

LSU Doctoral Dissertations

With the expansion of the human population and associated industries there is a concomitant increase in both resource utilization and the production of waste and deleterious by-products. Mercury is a naturally-occurring toxic metal with a complicated and unique biogeochemical cycle, and is often a contaminant of ecotoxicological concern in unindustrialized aquatic habitats. The research described herein was designed to elucidate multiple aspects regarding the behavior of mercury in oligohaline wetland habitats, particularly with respect to edaphic and vegetative effects, through a monitoring and characterization study as well as a series of manipulative experiments. The observational study, conducted in the wetlands …

Parent Education In A Child Welfare Setting: Understanding Maltreatment Following An Intervention For Parents And Their Infants, Toddlers, And Pre-School Children, Rhenda Hotard Hodnett

LSU Doctoral Dissertations

Child abuse and neglect is a complex, multi-faceted problem that often has lifelong, negative consequences for its victims; most significantly affecting infants, toddlers and pre-school age children. Parenting classes are the most common intervention used by child welfare agencies as a means to prevent repeat maltreatment, yet there is very little research involving these targeted families. Prior research has primarily focused on the prevalence of and risk factors for child maltreatment, with much less attention on specific parenting program outcomes as implemented in a child welfare setting. In 2005, focusing on a more deliberate and systematic approach in the use …

Model Based Analysis Of Some High Speed Network Issues, Suman Kumar

LSU Doctoral Dissertations

The study of complex problems in science and engineering today typically involves large scale data, huge number of large-scale scientific breakthroughs critically depends on large multi-disciplinary and geographically-dispersed research teams, where the high speed network becomes the integral part. To serve the ongoing bandwidth requirement and scalability of these networks, there has been a continuous evolution of different TCPs for high speed networks. Testing these protocols on a real network would be expensive, time consuming and more over not easily available to the researchers worldwide. Network simulation is well accepted and widely used method for performance evaluation, it is well …

Seventh-Grade Curriculum In Probability (A Guide For Teachers), David Nganga Njenga

LSU Master's Theses

A review of the literature indicates that teachers try to make connections between experimental and theoretical probabilities while teaching their students, but these connections are often not very clear. This greatly increases misconceptions students have about probability. This thesis presents a treatment of teaching probability that is geared for seventh grade and intended to minimize the misconceptions that both teachers and students may have. We present a concise mathematical exposition of finite probability models as well as collection of examples and activities, so as to help teachers and students organize their thinking and minimize misconceptions. The various examples and activities …

Effects Of Serum Addition To Culture Medium On Gene Expression In Day-7 And Day-14 Bovine Embryos, Jaime Manuel Angulo Campos

LSU Master's Theses

The addition of serum to embryo culture media may alter gene expression and trigger development of Large Offspring Syndrome. The objectives of this study were to determine gene expression levels in embryos cultured in the absence or presence of 5% calf serum and compare these expression patterns to in vivo derived embryos (IVD), and to determine the effects of serum on the length of day-14 embryos. Abattoir derived oocytes were fertilized and cultured in mSOFaa. At 72 hours post-insemination (hpi), embryos were randomly allocated into two treatments: mSOFaa without and with 5% calf serum. Embryos were then cultured to 168 …

Macular Pigment Optical Density During Pregnancy And Its Relationship To The Diet, Alicia Page

LSU Master's Theses

Women, compared to men, are at higher risk for age-related macular degeneration (AMD), the leading cause of blindness in the elderly. The accumulation of dietary carotenoids, lutein (L) and zeaxanthin (Z) within the macula make up macular pigment and provide important protection to the retina. Macular pigment optical density (MPOD) gives a measure of macula pigment density. MPOD has been shown to be influenced by fruit and vegetable L and Z and docosahexanoic acid (DHA, 22:6n-3), cold water marine fish being the dietary source. A high MPOD may protect against AMD. Intake of DHA by women is low (40-120 mg/d) …

Design And Development Of Chiral And Achiral Molecularly Imprinted Stationary Phases, Jason Paul Lejeune

LSU Doctoral Dissertations

Although the cross-linker can comprise over 80% of the polymer composition, improving the nature of the cross-linker in molecularly imprinted polymers has not been studied extensively. The goal of this research is to develop novel cross-linking monomers to either use in the One MoNomer Molecularly Imprinted Polymer system (OMNiMIP) or use in conjunction with other commercially available cross-linkers and functional monomers. Chapter 2 contains research into the understanding of the performance of a new cross-linking monomer (N, O - bismethacryloyl ethanolamine, NOBE) discovered in the Spivak Research Group. The ability of this monomer to outperform traditional two monomer systems in …

Urate Responsive Marr Homologs, Inoka Chinthana Perera

LSU Doctoral Dissertations

Differential gene expression in response to internal and external stimuli is studied in detail to understand the intricate mechanisms underlying response to various environmental stressors in microorganisms. MarR family transcriptional regulators have been studied for their involvement in such mechanisms. This work elucidates the mechanism of urate-induced attenuation of DNA binding of HucR, a MarR homolog, and extends this mechanism to describe a novel subfamily of MarR homologs responsive to urate, proposing a physiological relevance of utilizing urate as a signaling molecule.

HucR (hypothetical urate regulator) binds to the shared promoter region between uricase and hucR genes. It has high …

The Role Of Old-Fashioned Racism: Disaggregating Symbolic Racism In The United States, Leslie Curtis Cox

LSU Master's Theses

Old-fashioned, biological, or "Jim Crow" racism is viewed by many in the political science and psychology literature to be largely a relic of the past. In the post-segregation era it has been replaced as a political force by symbolic racism, although its residual effect still operates within symbolic racism as negative racial affect. Symbolic racism is thought of as a coherent belief system that describes whites‘ attitudes not only in the United States, but in some European democracies as well. This conceptualization of symbolic racism ignores the differences in the historical legacy of racism across different regional and demographic contexts. …

Revealing The Role Of Receptor Wsx1: A Double-Edged Sword In Tumor Progession, Denada Dibra

LSU Doctoral Dissertations

Tumor initiation and progression are dependent on both aberrant gene expression in tumor cells and the communication between tumor cells and its micro- and systemic microenvironment. Many tumor suppressor genes and oncogenes have been characterized to suppress or promote tumor growth, but fewer genes in tumors are well-characterized as interacting with immune cells in the host to promote or inhibit tumor growth. The interleukin (IL) 27 receptor WSX1 is expressed in immune cells and induces an IL27-dependent immune response. Opposing this conventional dogma, our initial results reveal a much higher level of WSX1 expression in multiple types of epithelial tumor …

Solid-Liquid Separation Technologies In The Conversion Of Bagasse To Liquid Fuel, Keith Miller

LSU Master's Theses

Development of liquid biofuels has entered a new phase of large scale pilot demonstrations. A number of plants in operation or under construction face the engineering challenges of creating a viable plant design, scaling up, and optimizing various unit operations. It is well-known that separation technologies account for 50-70% of both capital and operating costs. Processes vary in terms of selection of unit operations; however, solid-liquid separations are likely to be a major contributor to the overall project costs. A typical process for ethanol production from biomass includes several solid-liquid separation steps. The nature of biomass derived materials makes it …

The Radiosensitization Effect Of Parthenolide In Prostate Cancer: Implications For Selective Cancer Killing By Modulation Of Intracellular Redox State, Yulan Sun

University of Kentucky Doctoral Dissertations

Parthenolide (PN), a major active component of the traditional herbal medicine feverfew, has been shown to have anti-inflammatory and anti-tumor properties. More remarkably, the cytotoxicity of PN seems selective to tumor cells but not their normal cell counterparts. In the present study, we investigate whether and how PN selectively enhances tumor sensitivity to radiation therapy by using prostate cancer cells LNCaP, DU145 and PC3, as well as normal prostate epithelial cells PrEC.

Our study demonstrates that inhibition of NF-κB pathway and suppression of its downstream target MnSOD are common mechanisms for the radiosensitization effect of PN in prostate cancer cells. …

Immobilization Of Mercury And Arsenic Through Covalent Thiolate Bonding For The Purpose Of Environmental Remediation, Lisa Y. Blue

University of Kentucky Doctoral Dissertations

Mercury and arsenic are widespread contaminants in aqueous environments throughout the world. The elements arise from multiple sources including mercury from coal-fired power plants and wells placed in natural geological deposits of arseniccontaining minerals. Both elements have significant negative health impacts on humans as they are cumulative toxins that bind to the sulfhydryl groups in proteins, disrupting many biological functions. There are currently no effective, economical techniques for removing either mercury or arsenic from aqueous sources. This thesis will demonstrate a superior removal method for both elements by formation of covalent bonds with the sulfur atoms in N,N’-Bis(2-mercaptoethyl)isophthalamide (commonly called …

Effects Of Meal Timing On Anabolic Hormone Status And Energy Metabolism In Neonatal Dairy Calves, Katherine Claire Simon

LSU Master's Theses

Twelve neonatal Holstein bull calves (38.52 ± 5.87 kg) were fed milk replacer at a fixed or varied meal time to determine the effects on metabolic hormone secretion, average daily intake, growth, and energy metabolism. Body weights were measured every two weeks from birth to 8 weeks. Rumen fluid was collected every two weeks from week 2 through 8. Serial blood collections were conducted every two weeks from week 2 through 8. Blood was collected, beginning at 0530, at 0, 15, 30, 45, 60, 75, 90, 105, 120, 135, and 150 minutes. Plasma was analyzed for ghrelin, leptin, growth hormone …

Hydrogen Production From Molasses Using Chlorinated Alkane-Contaminated Groundwater As An Inoculum, Hector Narez

LSU Master's Theses

The Scenic Highway area of the PetroProcessors of Louisiana, Inc. (PPI) Superfund site located near Baton Rouge, LA, has groundwater contaminated with a variety of chlorinated alkanes (e.g., 1,2-dichloroethane, 1,2-dichloropropane) and alkenes (e.g., trichloroethene and vinyl chloride). In March 2009, a field-scale pilot test was conducted to evaluate the efficacy of injecting diluted agricultural feed grade molasses into the groundwater in an effort to stimulate in-situ reductive dechlorination of these chlorinated contaminants. Because H2 plays an important role as an electron donor in the metabolism of reductively dechlorinating bacteria, in support of the pilot-scale effort, experiments described in this thesis …

Modulation Of Cholinergic Signaling In Embryonic Zebrafish: Anatomical And Behavioral Consequences, Evdokia Menelaou

LSU Doctoral Dissertations

Smoking during pregnancy remains a major health concern in the United States. Nicotine is one of the main ingredients of cigarettes and a neurotoxicant which has been purported to affect many aspects of nervous system development causing long-term abnormalities in the offspring. We took advantage of the zebrafish model to investigate the effects of nicotine in nervous system anatomy and function. It was previously reported that embryonic nicotine exposure causes pathfinding errors in secondary motoneuron (SMN) axons through the activation of nicotine acetylcholine receptors (nAChRs). However, the nicotine-induced effects on SMN pathfinding coincided with muscle degeneration. We hypothesized that nicotine …

Sorption Mechanisms Of Zinc In Different Clay Minerals And Soil Systems As Influenced By Various Natural Ligands, Mohammed Hashem Stietiya

LSU Doctoral Dissertations

The bioavailability and fate of Zinc (Zn) in soils is influenced by reactions occurring at the water-mineral interface. Understanding Zn interaction with mineral surfaces is essential to the understanding of Zn fate and toxicity. In this study, adsorption experiments investigated the impact of ligands and pH on the adsorption of Zn to mineral surfaces. X-Ray Absorption Fine Structure Spectroscopy (XAFS) was used to elucidate the adsorption mechanisms of Zn to mineral surfaces as impacted by ligands. Impact of ligands on Zn adsorption was dependent on mineral type and pH of the system. XAFS analysis showed that adsorption mechanisms of Zn …

Synthesis And Characterization Of Rare Earth-Nickel-Gallium Ternary Intermetallics, Kandace R. Thomas

LSU Doctoral Dissertations

The structural and physical characterization of several early and latter rare earth Ln-Ni-Ga systems, which include Ln2NiGa12 (Ln = Pr, Nd, Sm), alpha-LnNiGa4 (Ln = Y, Gd – Yb) and beta-LnNiGa4 (Ln = Tb – Ho) will be presented in this work. These systems are thermodynamically located within a copious, robust phase space and provide a rich understanding of how slight modifications to synthetic preparations can yield the adoption of different structure types in a Ga-rich regime. Each of these phases is made up of well-studied substructures which lend an additional angle of apperception as to how their structure and …

Pharmaceutical Compounds In Treatment Wetlands: Potential Removal And Effects On Microbial Processes, Jeremy Landon Conkle

LSU Doctoral Dissertations

active compounds (PhACs) have been detected in the aquatic environment as a result of loading from various sources. In Louisiana, USA, many municipalities treat wastewater using natural systems, such as lagoons and wetlands, rather than using conventional wastewater treatment technologies and may discharge PhACs into the environment. These treatment systems are not designed to remove PhACs from wastewater, nor is it currently a regulatory requirement. Research on the fate of PhACs in the environment is needed to understand impacts on Louisiana’s important coastal system. Wastewater sampling for PhACs at the Mandeville, LA wastewater treatment plant (WWTP) determined that this system …

Structure And Organization Of Canopy Bird Assemblages In Lowland Neotropical Rainforests, David Lawrence Anderson

LSU Doctoral Dissertations

Although birds of the forest canopy are an important component of tropical forest ecosystems, difficulty accessing the forest canopy has limited the advancement of knowledge pertaining to this group of species. Here I test methods for the study of canopy birds in lowland Neotropical rainforests, and identify recurring patterns of community structure in canopy bird assemblages as well as processes potentially responsible for these patterns. I used three methods to assess differences in ground-based and canopy-based methods for detecting forest birds in a 100-ha plot of lowland rainforest in northern Honduras: (1) point counts from the ground; (2) repeat censuses …

Caring Attitudes Among Child Welfare Caseworkers: Associations With Client Participation In Services, Karen Faulk

LSU Doctoral Dissertations

The purpose of this study was to determine if there is an association between the caring attitudes and commitment toward clients of child welfare workers and their clients’ completion of a parenting education program. This line of inquiry is intended to expand the scope of research on caring attitudes associated with child welfare workers intent to remain employed. A logical extension of identifying characteristics associated with child welfare workforce retention is to determine if those characteristics are also associated with positive client outcomes. Part of the examination of worker caring attitudes involved testing the Child Welfare Inventory (CWI), a modified …

The Roles Of Transcription Factors In Nucleotide Excision Repair In Yeast, Baojin Ding

LSU Doctoral Dissertations

Nucleotide excision repair (NER) is a conserved DNA repair mechanism capable of removing a variety of helix-distorting lesions, such as UV-induced cyclobutane pyrimidine dimers (CPDs). NER can be grouped into two pathways: global genomic NER (GGR), which refers to repair throughout the genome, and transcription coupled NER (TCR), which refers to a repair mechanism that is dedicated to the transcribed strand (TS) of actively transcribed genes. In yeast S. cerevisiae, Rad7, Rad16, and Elc1 are specifically required for GGR. TCR is believed to be initiated by RNA polymerase II (Pol II) stalled at a lesion in the TS of a …