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Effect Of Clinically Relevant Mechanical Forces On Smooth Muscle Cell Response In Model Of Balloon Angioplasty, Kara Acampora

All Dissertations

Restenosis remains a common problem affecting the patency of endovascular intervention such as balloon angioplasty and stent placement as treatments for atherosclerosis. Denudation of the endothelial layer and the increased injury from balloon deployment can cause phenotypic changes in surrounding vascular smooth muscle cells (SMCs) in vivo. The presented work modeled this mechanical environment in vitro to investigate the role of the altered mechanical environment on the phenotypic response of SMCs. Through the system design and CFD channel characterization, a six-independent-channel system providing low oscillating wall shear stress (WSS) was manufactured to apply concurrent shear and tensile forces with uniform …

Wild Pig Habitat Use, Substrate Disturbance, And Understory Vegetation At Congaree National Park, Scott Zengel

All Dissertations

Substrate disturbance by wild pigs ( Sus scrofa L.), mainly wild pig rooting, was evaluated bi&ndashmonthly over three years in fixed 1,000 m2 plots at Congaree National Park, South Carolina, USA. The study compared hog substrate disturbance among four habitats: three mature wetland floodplain forest types (mixed bottomland hardwoods, cypress&ndashtupelo swamp, seepage floodplain forest), and successional upland pine flatwoods adjacent to the floodplain (including former pine plantation). New disturbance included fresh signs of hog substrate disturbance. Total disturbance included both new and older hog disturbance still visible on the landscape (equivalent to all disturbance that would be recorded under less …

Modeling And Control Of Piezoactive Micro And Nano Systems, Saeid Bashash

All Dissertations

Piezoelectrically-driven (piezoactive) systems such as nanopositioning platforms, scanning probe microscopes, and nanomechanical cantilever probes are advantageous devices enabling molecular-level imaging, manipulation, and characterization in disciplines ranging from materials science to physics and biology. Such emerging applications require precise modeling, control and manipulation of objects, components and subsystems ranging in sizes from few nanometers to micrometers. This dissertation presents a comprehensive modeling and control framework for piezoactive micro and nano systems utilized in various applications.
The development of a precise memory-based hysteresis model for feedforward tracking as well as a Lyapunov-based robust-adaptive controller for feedback tracking control of nanopositioning stages are …

Optimization Of Biodiesel Production From Crude Cottonseed Oil And Waste Vegetable Oil:Conventional And Ultrasonic Irradiation Methods, Xiaohu Fan

All Dissertations

Biodiesel, derived from the transesterification of vegetable oils or animal fats with simple alcohols, has attracted more and more attention recently. As a cleaner burning diesel alternative, biodiesel has many attractive features including: biodegradability, nontoxicity, renewability and low emission profiles.
Although cottonseed oil was the first commercial cooking oil in the U.S, it has progressively lost its market share to some vegetable oils that have larger production and less cost. However, regarding the active researches on biodiesel production from vegetable oils, there is a promising prospective for the cottonseed oil as a feedstock for biodiesel production, which may enhance the …

Novel Xanthine And Oxanine Dna Glycosylase Activities In Yeast And Mammalian Systems, Liang Dong

All Dissertations

DNA that stores genetic information is frequently damaged in cells. The DNA bases carrying an exocyclic amino group [adenine (A), guanine (G), cytosine (C)] encounter deamination even under physiological conditions. Xanthine (X) and the newly discovered oxanine (O) are derived from deamination of guanine; they are potentially cytotoxic and mutagenic lesions. However, in yeast and eukaryotes, studies on the enzymatic repair of these lesions are limited.
In the yeast, Schizosaccharomyces pombe thymine-DNA glycosylase (Spo TDG) is homologous to human thymine-DNA glycosylase (hTDG), an enzyme that removes thymine from T/G pair. It was reported that Spo TDG contains uracil DNA glycosylase …

Agritourism As A Viable Strategy For Economic Diversification: A Case Study Analysis Of Policy Options For The Bahamas, Erecia Hepburn

All Dissertations

This research examines the prospects for developing an economic diversification policy for The Bahamas, utilizing agritourism. The Bahamas is plagued with the dominance of one traditional sector, tourism combined with the lack of economic innovation and the inability to maintain domestic demand for food security, which has the potential for economic crisis if there are any serious 'external shocks' or setbacks in mainstream tourism. Such a possible drop in tourism is most evident from experiences in 2001 with the Straw Market fire of Sept 4th, and the terrorist attacks in America on September 11th, coupled with the escalating cost of …

Dna Deamination Repair Enzymes In Bacterial And Human Systems, Rongjuan Mi

All Dissertations

DNA repair enzymes and pathways are diverse and critical for living cells to maintain correct genetic information. Single-strand-selective monofunctional uracil DNA glycosylase (SMUG1) belongs to Family 3 of the uracil DNA glycosylase superfamily. We report that a bacterial SMUG1 ortholog in Geobacter metallireducens (Gme) and the human SMUG1 enzyme are not only uracil DNA glycosylases (UDG), but also xanthine DNA glycosylases (XDG). Mutations at M57 (M57L) and H210 (H210G, H210M, H210N) can cause substantial reductions in XDG and UDG activities. Increased selectivity is achieved in the A214R mutant of Gme SMUG1 and G60Y completely abolishes XDG and UDG activity. Most …

Vascular Tissue Engineering: The Creation Of Living, Non-Thrombogenic, Functional Blood Vessels Based On Elastin Scaffolds, Aditee Kurane

All Dissertations

Cardiovascular diseases are the leading cause of death worldwide. Blood vessel replacement is a common treatment for vascular diseases such as atherosclerosis, restenosis and aneurysm, with over 300,000 bypass procedures performed each year. However, vein grafts are limited due to their availability. Although synthetic vascular replacements have been successful for large diameter arteries, they have shown minimal success in arteries with diameters <6mm. This is because most synthetic materials induce thrombus formation which, within a few months of implantation, causes failure of the vascular graft due to occlusion. Tissue engineering is a promising approach to the fabrication of non-thrombogenic vascular grafts, but a reliable and expandable cell source for tissue-engineered vascular graft (TEVG) has not been established.
The work presented here is motivated by the current unavailability of an ideal tissue engineered blood vessel replacement. Our overall goal is to create a living tissue engineered vascular graft that is biodegradable, non-thromobogenic, presents low antigenicity and …

Experimental And Modeling Studies For Optimizing Flocculant-Aided Sediment Retention Ponds, Byung Joon Lee

All Dissertations

Attempts to control sediment-containing runoff and associated water quality problems have involved the establishment of many small to medium sediment retention ponds and the injection of nonionic and anionic polyacrylamide (PAM) flocculants to enhance colloid removal. However, to date use has been driven more by practicing engineers and trial-and-error approaches than by logical and consistent design approaches. Therefore, the purpose of this research was to optimize colloidal clay removal in PAM-aided sediment retention ponds by applying experimental and theoretical methodologies.
Initially, simple measurement techniques for the molecular weight (MW) and charge density (CD) of various PAMs were tested and their …

Development And Evaluation Of A Minimally Invasive Sampling Technique To Estimate The Age Of Living Birds, Crissa K. Cooey

Graduate Theses, Dissertations, and Problem Reports (ETD)

Using pest species in initial studies of pentosidine (Ps) aging research for birds may be the catalyst to discovering more effective population control strategies for pest, invasive, and hard to manage birds. Pentosidine is an irreversible, stable, fluorescent, collagen cross-link, created through the Maillard reaction, which has been found to accumulate throughout the lifetime of an organism in various body parts such as skin, lens crystalline, and dura matter. Pentosidine assays are more accurate at determining the age of adult birds in comparison to plumage coloration, eye and mouth color, feather wear, and molt sequences due to the discovery that …

Effects Of The Antimicrobial Agent Triclosan On Bacterial Resistance To Disinfection In Wastewater Treatment Processes, Meilin Liu

Graduate Theses, Dissertations, and Problem Reports (ETD)

2-(2,5-Dichlorophenoxy)-5-chlorophenol or Triclosan is a widely used antimicrobial agent included in a multitude of products, such as soap, toothpaste, and personal care products.;The objective of this research was to investigate the effects of Triclosan on the resistance of activated sludge bacteria to conventional disinfection processes applied in wastewater treatment processes, such as chlorination and UV.;Specific Aim 1. A complex bacterial community collected from an active sludge was acclimated over several sub-cultures in the presence of different concentrations of Triclosan (from 0.0 to 20 mg L-1) and then exposed to sub-lethal doses of chlorine and UV irradiation. Determination of bacterial viability …

Caveolin-1 Recruitment To The Trailing Edge Of Motile Cells Results In Focal Adhesion Disassembly And Nascent Interaction With Actin Stress Fibers, Andrew Beardsley

Graduate Theses, Dissertations, and Problem Reports (ETD)

The protein caveolin-1 has been shown to positively affect angiogenesis and vascular remodeling in vivo via studies using knockout mice. In fact, defects in these two processes are among the major hallmarks of an otherwise benign caveolin-null phenotype. Current dogma on the function of caveolin-1 does not predict or account for these deficits. The overall objective of the following studies was to uncover the role of caveolin-1 in angiogenesis and vascular remodeling through study of the protein in cell-substratum remodeling during cell motility in vitro.;In the first study, caveolin-1 and its parent organelle, caveolae, conspicuously polarize to the rear of …

Effect Of Dietary Lysine And Genetics On Indices Of Energy And Protein Metabolism In Rainbow Trout And Alterations In The Mitochondrial Proteome In Broilers Fed A Lysine-Deficient Diet, Stephanie K. Pomeroy

Graduate Theses, Dissertations, and Problem Reports (ETD)

How an organism reacts to consuming a lysine deficient diet was examined in two different circumstances. First, the responses of ten different genetic lines of rainbow trout were observed while consuming a lysine-deficient (LD) diet, used to mimic a soybean meal-containing diet. The aquaculture industry is investigating the incorporation of soybean meal into carnivorous fish diets to alleviate the need for fishmeal. If soybean meal is incorporated into the diet, an assessment of the genetic strains of fish used in the aquaculture industry today must be performed since differences in genetics have been shown to effect growth. When compared to …

Effects Of Rate Of Feedback And Reinforcement On Novel Responding, Vennessa L. Walker

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ten middle-school students were assigned to receive feedback and token reinforcement either every 1 min (HR) or every 15 min (LR). Subjects used a computer program to learn to perform 5 basic algebra skills at high rates and high accuracy. Subjects were yoked with a partner for practice so that each member of the pair completed the same number of items per skill. Subjects were provided with cumulative review worksheets and then were tested for distraction, adduction, and retention. Results suggest that HR facilitates faster acquisition of skills as well as better performance on cumulative reviews, distraction, and retention tests. …

Functional Characterization Of Hexokinase-Like 1 (Hkl1) From Arabidopsis Thaliana, Abhijit Karve

All Dissertations

Arabidopsis hexokinase1 (AtHXK1) is a moonlighting protein with roles in both glucose signaling and catalysis. In this study, we first cloned and characterized the six HXK related genes from Arabidopsis. Three of the six encoded proteins were shown not to phosphorylate hexoses and thus, are designated as hexokinase-like (HKL) proteins. Though they are only 50% identical to HXK1, the amino acid sequences of HKL1 and HKL2 both have well conserved glucose binding domains and other recognized structural elements. The possible basis for their lack of catalytic activity was further probed by site-directed mutagenesis and ultimately was attributed to a suite …

Parental Influences In Child Obesity, Janel Lynn Calinisan

Loma Linda University Electronic Theses, Dissertations & Projects

One of the greatest concerns in American society is peoples’ health. In the past several years there has been an overwhelming increase in obesity in Americans. This concern relates not only to adults, but also to children, as more are found to be overweight. Many factors have been suggested as to why more children are becoming obese, including parenting, demographics, physical activity, nutrition, and biological factors. Studies have shown that parental influence or involvement can be related to child obesity such that neglected children were more likely to be obese in adolescence and sustain it through adulthood. In order to …

Buccal Bone Changes Following Rapid Maxillary Expansion (Rmf), Long-Term Results, Elena S. Iacob

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to use Cone Beam Computed Tomography (CBCT) images to quantitatively evaluate buccal bone changes of maxillary first premolar (P1), second premolar (P2) and first molar (M1) shortly after Rapid Maxillary Expansion (RME) and at the end of orthodontic treatment, as well as to evaluate the variables that may be associated with the short-term and long-term changes. Forty-seven consecutive patients (25 males and 22 females) with a mean age of 14.5years and who required RME as part of their orthodontic treatment and had pre-RME (T1) and post-RME (T2) CBCT images available were used for the …

Sensory Isolation In Flotation Tanks: Altered States Of Consciousness And Effects On Well-Being, Anette Kjellgren, Fransica Lyden, Torsten Norlander

The Qualitative Report

A qualitative analysis (The Empirical Phenomenological Psychological method) of interviews involving eight patients (depression, burn-out syndrome, and chronic pain) was carried out in order to obtain knowledge regarding the effects of flotation tank therapy. This knowledge might be helpful for both professionals and potential floaters. The analysis resulted in 21 categories, which were summarized as four themes: (a) experiences during flotation, (b) perceived effects afterwards, (c) technical details, and finally (d) the participants ́ background, motivation, and expectations. Floating was perceived as pleasant. An altered state of consciousness was induced, varying from a milder state including profound relaxation and altered …

How Does Emotional Intelligence And Shared Vision Affect Teamwork Performance?, Ed Mahon

Student Scholarship

There is a vast literature on the emotional intelligence (EI) of individuals, but comparatively little on team EI. We report findings of a qualitative inquiry involving 36 members of twelve IT teams – half of them effective and half less so – to explore the relationship between team EI and team performance. Trust, conflict resolution skills and team communication are seen to differentiate effective and less effective teams, as is the ability to adapt shared vision to changes in project specification. The research supports that the teams possess emotional intelligence and that it powerfully influences how they function and to …

The Link, Vol 2, No. 12, December 2008, Illinois State University, Center For Integrated Professional Development

The Link

Newsletter for the Illinois State University Center for Integrated Professional Development

Sense Of Humor, Stress And Coping, And Outcomes In Children's Lives, Lambertha Okhuizen-Stier Phd, Mph, Rn

Dissertations

Children are confronted with many stressors in their environment which may bring about symptoms such as anxiety, sadness, worry, aggressiveness, hyperactivity, restlessness, or low self esteem (Sharrer & Ryan-Wenger, 2002). To prevent the short and long term effects of stress, children may use coping strategies to manage or alter stressful life events (Lazarus & Folkman, 1984). This study explores the relationships between stress and sense of humor among school-age children. A sample of 106 students (and parents/guardians) in the San Diego Unified School District (SDUSD) returned self-report instruments packets containing the Multidimensional Sense of Humor Scale for Children, and the …

Investigation Of The Vesicular Stomatitis Virus Matrix Protein: Uncoating And Assembly, Chad E. Mire

Theses and Dissertations (ETD)

Vesicular Stomatitis Virus (VSV) is a simple, enveloped, nonsegmented negative-strand RNA virus and is the prototype rhabdovirus to study viral entry, transcription, replication, and assembly. The matrix protein (M) of VSV is a central component of the viral replication cycle. While being the smallest of the viral proteins it is multifunctional and is involved in uncoating, cytopathic effects (CPE), and assembly of the virus. M protein interactions involved in the uncoating and assembly of VSV have been examined in this dissertation.

Uncoating of VSV involves dissociation of M from the ribonucleoprotein core (RNPs) of the virus. Current models of VSV …

Regulation Of The Human Parainfluenza Virus (Hpiv3) Fusion Protein, Amanda Ruth Chapman

Theses and Dissertations (ETD)

Paramyxoviruses include a number of important human pathogens, including measles virus, mumps virus, and the human parainfluenza viruses (hPIV) 1-4, as well as several animal pathogens, such as Sendai virus, Nipah virus and Hendra virus. The creation of effective drugs and vaccines against this family of viruses would play an important role in decreasing the prevalence of these viruses and contributing to the health of both humans and animals worldwide. The purpose of this work was to determine how the fusion (F) protein is regulated with a focus on the heptad repeat B (HRB) region of the F protein located …

Role Of The Lpa2 Receptor In Protecting Against Apoptosis, Shuyu E

Theses and Dissertations (ETD)

Lysophosphatidic acid (LPA) is a naturally occurring lipid mediator. It exists abundantly in biological fluids such as serum, saliva, follicular fluid, seminal fluid and malignant effusions and induces a vast array of biological responses affecting cell growth, survival, differentiation, migration and morphology. We recently identified lysophosphatidic acid (LPA) as a potent antiapoptotic agent for the intestinal epithelium. Based on computational modeling octadecenyl thiophosphate (OTP) was synthesized: a novel rationally designed, metabolically stabilized LPA mimic. OTP was more efficacious than LPA in reducing g-irradiation-, camptothecin-, or TNF-a/cycloheximide-induced apoptosis and caspase 3, 8 and 9 activity in the IEC-6 cell line. The …

The Role Of Fgf Signaling In Retinal Development, Abbie A. Hartge

Theses and Dissertations (ETD)

The development of the retina is a precise balance between intrinsic competence and extrinsic factors. This interplay is known to regulate the generation of cell types in the developing retina and similar mechanisms have been found in other regions of the CNS. In the developing retina, FGFs are a large family of secreted polypeptide growth factors. Fgf15 is the major Fgf expressed during retinal development in mice. Fgf15 is an example of an FGF that has been shown to control proliferation, cell fate specification, differentiation and migration during development. In this thesis I used analysis of specific genes throughout retinal …

Synthesis And Evaluation Of Tetramic Acids As Antimicrobial Agents, Jason B. Wilson

Theses and Dissertations (ETD)

As bacterial infectious diseases are a major cause of morbity and mortality throughout the world, and many causative organisms are resistant to currently available antibiotics, the motivation for the development of new drugs is readily apparent. A number of natural products exhibiting antimicrobial activity possess a tetramic acid (2,4-pyrrolidinedione) functional group. As their antibacterial mechanism of action is different from that of many of the currently available antibiotics, these compounds have potential to serve as a basis for a pharmacophore in synthetic compounds. However, toxicity to eukaryotic cells is frequently a problem with currently known tetramic acids. The purpose of …

Studies Of Entry, Reverse Transcription, And Regulation Of Splicing In Retroviruses, Timothy A. Sullivan

Theses and Dissertations (ETD)

The study of retroviruses and their lifecycle has contributed immensely to our knowledge of the world of biology and medicine. The central dogma of the basic flow of genetic information was shattered when the discovery that retroviruses copy their RNA genome into DNA was made. The same enzyme that performs this step, reverse transcriptase (RT), also revolutionized molecular biology when it was used as a tool to generate full length cDNA clones of expressed genes. The impact of retroviruses on the medical field has been extremely exciting as the ideas of using retroviral vectors to deliver genes providing long term …

Torsina And The Pathophysiology Of Dyt1 Dystonia, Yu Zhao

Theses and Dissertations (ETD)

The goal of my dissertation work was to examine the systems biology of torsinA, a DYT1 dystonia-associated protein, by using rodent model systems. TorsinA is a putative ATPase associated with a variety of cellular activities (AAA+). Deletion of glutamic acid residue 302/303 in TOR1A is causally associated with many cases of early-onset primary dystonia.

In our work, transient forebrain ischemia and sciatic nerve transection were used as central and peripheral neural perturbations, respectively, to gain insight into the in vivo role(s) of torsinA. Moreover, transgenic mouse models that overexpress either human mutant torsinA (hMT) or wild-type torsinA (hWT) were used …

Controlled Release Of Insulin And Modified Insulin From A Novel Injectable Biodegradable Gel, Om Anand

Theses and Dissertations (ETD)

The objective of the study was to develop a controlled release dosage form of
insulin, which can provide basal concentrations of insulin in diabetic rats for 1 to 2 weeks after a single subcutaneous injection.
A biodegradable injectable drug delivery gel was prepared by dissolving a
biodegradable polymer, polylactic-co-glycolic acid (PLGA), in biocompatible
plasticizer(s), triethyl citrate (TEC) and/or acetyl triethyl citrate (ATEC). Insulin was
then loaded into the blank gel to form an insulin suspension in the polymer solution.
After the insulin-loaded gel was injected subcutaneously, the plasticizer(s) dissolved in the aqueous media and were gradually taken away from the …

Communicative Functions Of Young Children's Visual Art, Clover Simms Wright

Graduate Theses, Dissertations, and Problem Reports (ETD)

How can young children use visual art to communicate? This study used Halliday's communicative functions of language (Halliday, 1973), to frame the answer to this question; Halliday's categories of communicative functions are: instrumental, regulatory, interactional, personal, heuristic, imaginative, and representational/informative. Five children, between the ages of three and five, were observed and interviewed as they voluntarily created visual art over a six-week period. In that time period, each of the seven functions of language was demonstrated collectively by the participants. The research was conducted by an educator employed in the early childhood setting. Qualitatively, this study confirmed that young children …