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Modeling Of Flexible Drug-Like Molecules : Qsar Of Gbr 12909 Analog Dat/Sert Selectivity, Kathleen Mary Gilbert

Dissertations

The dopamine reuptake inhibitor GBR 12909 and related dialkyl piperazine and piperidine analogs have been studied as agonist substitution therapies acting on the dopamine transporter (DAT) to treat cocaine addiction. Undesirable binding to the serotonin transporter (SERT) can vary greatly depending on the specific substituents on the molecule. This study uses Comparative Molecular Field Analysis (CoMFA) and Comparative Molecular Similarity Indices (CoMSIA) techniques to determine a stable and predictive model for DAT/SERT selectivity for a set of flexible GBR 12909 analogs.

Families of analogs were constructed from six pairs of naphthyl-substituted piperazine and piperidine templates identified by hierarchical clustering as …

Mechanics Of Biocell Landfill Settlements, Chamil Hiroshan Hettiarachchi

Dissertations

Prediction of landfill gas generation and settlements are of concerns in design and maintenance of biocell landfills. Accurate settlement prediction is essential for design of piping systems used for the delivery of re-circulated leachate and recovery of landfill gas. Landfill settlement is the result of change in overburden stresses and biodegradation of waste. Biodegradation-induced settlement results from the re-arrangement of waste skeleton in response to the decomposition of waste mass.

Current practice of landfill settlement modeling is predominantly empirical, thus most of the available techniques make no attempt to simulate the real mechanisms of waste settlement. Traditionally compressibility index is …

Direct Numerical Simulations And Experimental Investigation Of Dielectrophoresis, Arun Thankamony John-Kadaksham

Dissertations

This dissertation deals with the numerical and experimental studies of the phenomenon of dielectrophoresis, i.e., the motion of neutral particles in nonuniform electric fields. Dielectrophoresis is the translatory motion of neutral particles suspended in a dielectric medium when they are subjected to an external nonuniform electric field. The translatory motion occurs because a force called the dielectrophoretic force, which depends on the spatial variation of the electric field, acts on the particles. As the generation of force involves no moving parts and the particles can be moved without touching them, dielectrophoresis can be used in many applications, including manipulation and …

Evaluating Rhizodegradation Of Petroleum Hydrocarbons And Polycyclic Aromatic Hydrocarbons In Wetland Sediments Containing Spartina Patens, Robert J. Lippencott

Dissertations

Biodegradation of petroleum hydrocarbons (PHC) and 16 polycyclic aromatic hydrocarbon (PAH) compounds was evaluated in sediments from a stormwater basin that was a former salt marsh at an active oil refinery. Spartina patens were grown in basin sediments during a field study and a greenhouse study over three consecutive growing seasons. Ninety percent (90%) survival was observed in field study plots containing sediments with <12% PHC. In the greenhouse study, planted and bulk sediments were monitored for PHC, PAH, microbial density, nutrients, pH, redox and root biomass at 2.5 and 7.5 cm in sediments with <12% PHC. The sediments contained on average 6.5% to 9.5% PHC and 56 to 124 parts per million (ppm) total PAH. The plants exhibited a 95% survival rate and added from 1% to 2% root biomass to the sediment. Microbial densities in planted sediments were significantly higher than in bulk sediments (p<0.05). Oxidizing conditions were prevalent in all treatments at both depths; however, reducing conditions developed in the planted sediments at 7.5 cm. PHC was 35% to 37% lower in the planted sediments vs. bulk sediment at the end of the study. Planted sediment PAH concentrations were generally lower than in bulk sediments. Low MW PAHs (2 and 3-Rings) were either absent or at relatively low concentrations in all treatments. Phenanthrene concentrations in bulk sediments did not change, but were reduced by 95% in planted sediments (p<0.01), with half-life estimates of 141 to 165 days at 2.5 cm. Temporal changes in high MW PAHs ( 4-Rings) were not observed over the greenhouse study period. Differences in PAH concentrations between planted and bulk sediments exhibited a decreasing trend with PAH molecular weight. Evaluation of differences in planted and bulk sediment PAH concentrations suggests that lower MW PAHs degrade better under oxidizing conditions, and higher MW PAHs under reducing conditions in the planted sediments. Comparison of planted and bulk sediment PAH concentrations links depth and redox conditions to decreases in PAH as a function of PAH MW. Therefore, it was concluded that spatio-temporal variations and cycling of redox conditions should be considered to properly evaluate biodegradation of PAH.

Simulation Of Creep In Nickel Based Single Crystal Superalloys, Yunhong Pang

Dissertations

Nickel based single crystal Superalloys are finding wide spread use in high temperature gas turbines and other similar applications because of their superior high-temperature strength and creep properties as compared to the other materials. This is due to two factors: solid solution and precipitation strengthening of the gamma (γ) and gamma prime (γ') phases, and the elimination of grain boundaries. Creep of Nickel based single crystal Superalloys are caused by two primary mechanisms, dislocation creep and diffusion creep. Several factors that affect the creep life of Nickel based single crystal Superalloys are the specific microstructure, stress, temperature and rafting. Also, …

Bioinformatics Study Of Mammalian Mrna Polydenylation, Haibo Zhang

Dissertations

Messenger RNA polyadenylation is one of the key post-transcriptional events in mammalian cells, which have influences on many aspects of mRNA metabolism. Several human diseases have been shown to associate with abnormal polyadenylation, highlighting the importance of this process. The availability of the complete sequence of human and mouse genomes, together with their gene expression data provides valuable resources to study mRNA polyadenylation on a system level. This dissertation addresses the following issues of mammalian mRNA polyadenylation through bioinformatics approaches: (1) the extensive documentation of several key aspects of polyadenylation sites in humans and mice on a genomic level; (2) …

High-Dimensional Indexing Methods Utilizing Clustering And Dimensionality Reduction, Lijuan Zhang

Dissertations

The emergence of novel database applications has resulted in the prevalence of a new paradigm for similarity search. These applications include multimedia databases, medical imaging databases, time series databases, DNA and protein sequence databases, and many others. Features of data objects are extracted and transformed into high-dimensional data points. Searching for objects becomes a search on points in the high-dimensional feature space. The dissimilarity between two objects is determined by the distance between two feature vectors. Similarity search is usually implemented as nearest neighbor search in feature vector spaces. The cost of processing k-nearest neighbor (k-NN) queries via a sequential …

The Control Of Frequency Of A Conditional Oscillator Simultaneously Subjected To Multiple Oscillatory Inputs, Christina L. Ambrosio

Dissertations

A conditional oscillator is one that requires input to oscillate. An example of such is the gastric mill network of the stomatogastric ganglion of the crab Cancer borealis which requires modulatory input from outside the stomatogastric ganglion and fast input from the pyloric network of the animal in order to become active. This dissertation studies how the frequency of the gastric mill network is determined when it is simultaneously subjected to two different rhythmic inputs whose timing may be mismatched. We derive a mathematical model of the gastric mill network and deduce that the difference in timing between the pyloric …

Characterization Of Mismatch Between Behavioral Stimuli And Frmi Data Using The Kalman Filter, Jason Steffener

Dissertations

The advance of blood oxygen level dependent function magnetic resonance imaging, (BOLD fMRI), allows researchers to non-invasively investigate the functioning human brain. The BOLD fMRI response to brief stimuli is called the hemodynamic response function (HRF), which can vary across brain regions and across subjects.

Models of the HRF are used to increase sensitivity of statistical maps; however, they often don't account for spatial and temporal variance. Physiological effects, such as learning, fatigue or habituation, introduce mismatch between statistical models and the data. Methods that use minimal a priori information and track time varying signals are able to show the …

Utility Of Remote Sensing Data In Retrieval Of Water Quality Consituents Concentrations In Coastal Water Of New Jersey, Ting Yu

Dissertations

Three important optical properties used for monitoring coastal water quality are the concentrations of chlorophyll (CHL), color dissolved organic matter (CDOM) and total suspended materials (TSM). Ocean color remote sensing, a technique to collect color data by detection of upward radiance from a distance (Bukata et al.,1995), provides a synoptic view for determining these concentrations from upwelling radiances. In the open ocean (Case-I), it is not difficult to derive empirical algorithms relating the received radiances to surface concentrations of water quality parameters. In coastal waters (Case-Il), there are serious unresolved problems in extracting chlorophyll concentration because of high concentration of …

The Role Of Puf3 Protein Interactions In The Regulation Of Mrna Decay In Yeast Saccharomyces Cerevisiae, Shervin Sean Houshmandi

Dissertations

The regulation of messenger RNA (mRNA) metabolism is an important step in proper gene expression. In many eukaryotic organisms this regulation can be mediated by a group of highly conserved RNA-binding proteins known as the Puf family of proteins. The yeast Saccharomyces cerevisiae has several proteins that belong to this family. One of the yeast Puf proteins, Puf3p, binds and regulates the COX17 mRNA, which codes for a protein involved in mitochondrial copper transport. Specifically, Puf3p stimulates the decay of COX17 mRNA. However, the precise mechanism of Puf3p binding and decay regulation is yet unknown. The goal of this research …

Culture And Motivation In Online Learning Environments, Frances A. Clem Edd

Dissertations

In the past, instructional design of online learning has largely ignored culture in the creation of online learning environments. Because research in the interaction of culture and online learning is very sparse, an exploratory, blended study was conducted to assess whether there is evidence that one measurable aspect of learners’ culture interacts with the online learning environment in ways that can be observed and identified, and whether this interaction impacts learners’ motivation and behavior in those environments. “Culture” is a complex concept consisting of many interrelated behaviors and values. For this reason, the study focused on one single aspect of …

Navigating The Change Of Life: The Menopausal Transition Of Thai Immigrant Women, Bulaporn Natipagon-Shah Phd, Msn, Rn

Dissertations

Given that women continue to live more than three decades after menopause and their health and well-being in later life are determined by quality of health during the menopausal transition, menopause has become an important issue in the healthcare arena. The growing number of immigrant women in the United States signifies a need for healthcare providers to develop cultural knowledge and sensitivity toward each immigrant group regarding the issue of menopause. The purpose of this qualitative study was to build a substantive grounded theory of the experiences of menopausal transition among Thai immigrant women in the United States. Data collection …

Cognitive Orthotics For Students With Cognitive Disabilities, James V. Yanna

Dissertations

This study examined the effectiveness of a hand-held computer to guide an individual with a moderate cognitive impairment as he or she completed a complex daily living task. Performance was compared with that occasioned by a human supervisor. A third condition, assistance first from a human supervisor, and then by the computerized orthotic, was also evaluated. The task selected was a baking task.

Subjects were nine students, ranging in age from 17 to 24 years. All subjects were classified as cognitively impaired according to the Michigan Special Education Rules and Regulations. Assessment information showed most to be performing at a …

Reconciling Temporalities: A Substantive Explanation Of The Origins Of Difficulty In The Nurse Patient Encounter, Marilyn Theresa Macdonald Phd

Dissertations

Nurses describe patients as difficult on a regular basis. Nursing research to date has assumed the existence of this phenomenon. Most studies have listed descriptors of the difficult patient and offered interventions for nurses to use to alter patient behavior. Locating of difficulty within the individual and failure to consider the context of the nurse patient encounter is problematic. The practice of locating difficulty in the individual absolves organizations and society of responsibility to work to change factors that contribute to the construction of difficulty. The purpose of this research was to move beyond a focus on the patient as …

Meaningful Learning: Reconciling The Tensions Between Constructivist And Environmentally Sustainable Pedagogy, Nancy Van Kannel-Ray

Dissertations

Critics of constructivism argue, in many ways correctly, that this approach to education is culturally and environmentally damaging because constructivism may not develop an understanding of the interdependence between the human community and the world in which people live. Advocates for environmentally sustainable pedagogy argue the importance of understanding patterns of thinking that allow communities to live sustainably. The purpose of this study is to resolve the tensions between the two pedagogical frameworks: constructivism and environmental sustainability.

The tensions are resolved in two ways. First, there are forms of constructivism that align in viable ways with the criteria critics argue …

The Glucose And Insulin Responsiveness Of The Rat Glucose-6-Phosphate Dehydrogenase Promoter, Daryl Arkwright-Keeler

Dissertations

The regulation of expression of some enzymes involved in glucose homeostasis and fat metabolism requires both insulin and glucose to elicit an effect, while the regulation of others requires only one. Glucose-6-phosphate dehydrogenase (G6PDH), an important enzyme involved in glucose homeostasis, has been shown to be transcriptionally regulated by carbohydrate feeding in rat liver, a diet regime that increases the levels of both glucose and insulin. Our lab had previously shown that insulin induces expression of G6PDH, thus we wanted to determine if glucose also induced G6PDH expression and if so, are the glucose and insulin responses mediated through identical …

Understanding Photosynthesis And Plant Cellular Respiration As “Nested Systems”: The Characterization Of Pre-Service Teachers’ Conceptions, Mary H. Brown

Dissertations

This dissertation project focused on pre-service elementary teachers' conceptions of the plant processes of photosynthesis and cellular respiration as being connected, occurring at multiple ecological levels, and working within "nested systems." Participants enrolled in a biology course designed for elementary education majors provided their views of the processes through a series of tasks with a peer, a semi-structured interview, and clarified both photosynthesisand plant cellular respiration directly following classroom instruction on the two topics. The instructor of the course was interviewed after a preliminary analysis of the participants' responses. Data were analyzed using the qualitative analysis computer program The Ethnograph …

Changes In Glial Cell Line Derived Neurotrophic Factor And Nerve Growth Factor Expression With Development, Age, Exercise And Hypertension, Bertha C. Rebimbas-Cohen

Dissertations

Neurotrophic factors are important for neuronal growth, survival, and maintenance of cell phenotype. Glial cell line-derived neurotrophic factor (GDNF) affects sensory, autonomic and somatic motor neurons and nerve growth factor (NGF) affects sensory and sympathetic neurons. NGF and GDNF are produced by cardiac muscle and have potent effects on sensory and autonomic neuronal innervation of blood vessels. Neural innervation plays a key role in blood vessel function. Since neural innervation of blood vessels may be regulated by growth factors, we wanted to determine what changes would occur to NGF and GDNF levels with maturity, exercise and hypertension.

Changes in GDNF …

Bufadienolides In The Chemical Defenses Of The Toads, Bufo Americanus And Bufo Fowleri, Catherine E. Merovich

Dissertations

I investigated the steroidal chemical defenses (bufadienolides) of Bufo americanus and Bufo fowleri. By the nature of their complex, biphasic life cycles, toads, like other amphibians are important components of aquatic and terrestrial habitats and are prey to numerous invertebrates and vertebrates. Bufadienolides are presumed to be important anti-predatory compounds although much of their chemical ecology is poorly understood. I investigated (1) ontogenetic variation in bufadienolides, (2) bufadienolides from adult parotoid secretion, (3) effectiveness of bufadienolides against a terrestrial predator, and (4) effectiveness of bufadienolides against an aquatic predator. I hypothesized that B. americanuswould have a more extensive …

The Feasibility Of Micromachined Dynamic Resonant Beam Coriolis True Mass Flow Meter, Sang Hwui Lee

Dissertations

The technological advances of micro-electro-mechanical systems (MEMS) in the past two decades have been remarkable for innovations in microfluidic systems as well as automotive applications such as pressure sensors and accelerometers. MEMS flow sensing has emerged as a field of interest in microfluidics, with a variety of sensing methods being miniaturized, such as thermal anemometry, ultrasonic sensing and flow measurement based on the Coriolis effect. Coriolis sensing is particularly attractive since, unlike most other methods which provide volumetric flow information, Coriolis sensing is capable of providing a direct, true mass flow measurement. Because of this advantage, Coriolis flow sensing has …

Development And Application Of Fractionation Procedure For Drinking Water Organic Matters, Yong Pu

Dissertations

USEPA mandates a control of disinfection by-products (DBPs) in finished drinking water and recommends reduction of natural organic matters (NOM), DBP precursors, to achieve this regulatory goal. Studies relating NOM with DBP include fractionation of water samples, characterization of collected organic fractions, fractions' formation potential tests, and jar or similar tests to remove NOM. This study discussed a current resin fractionation procedure on principle, procedure, and its efficiency when applied to water samples of low NOM (< 5mgIL). The primary objective of this research is to develop a fractionation procedure intended for water of low NOM by carefully applying mass balance concept through each fraction's fractionation and a selection of stable ion exchange resins. A new protocol was presented with triple columns of XAD-8 adsorption resin, one column of AG-MP-50 cationic resin, and another column of WA 10 weak anionic resin in sequence. This protocol was experimented and confirmed for its efficiency (±10% loss of mass) with samples from Canal Road (CR) and Raritan Millstone (RM) surface water treatment plants (WTPs) in central New Jersey. The second objective of this study is to develop a statistical model with a potential of online delineation of organic fractions of NOM. The resulting model based on samples of Passaic Valley Water Commission (PVWC) WTP in northern New Jersey was applied to predict organic fractions of samples from CR and RM plants. Paired T-test (paired t ratio 1.15 < t critical 2.02) indicated a good correlation between the predicted and actual fraction concentration. Finally, samples of Middlesex Water Company (MWC) were fractionated and Trihalomethane formation potential tests (THMFP) on collected fraction showed hydrophilic matters possessed a higher potential to produce TTHM in finished water than hydrophobic matter. Jar tests indicated while coagulation was effective in removing hydrophobic matter, it may not be optimum for removal of hydrophilic matter.

This study developed an accurate fractionation procedure for low NOM waters. It provided a better understanding of organic matter transformation at different treatment …

Pattern Discovery In Structural Databases With Applications To Bioinformatics, Sen Zhang

Dissertations

Frequent structure mining (FSM) aims to discover and extract patterns frequently occurring in structural data such as trees and graphs. FSM finds many applications in bioinformatics, XML processing, Web log analysis, and so on. In this thesis, two new FSM techniques are proposed for finding patterns in unordered labeled trees. Such trees can be used to model evolutionary histories of different species, among others.

The first FSM technique finds cousin pairs in the trees. A cousin pair is a pair of nodes sharing the same parent, the same grandparent, or the same great-grandparent, etc. Given a tree T, our …

Tide-Influenced Contaminant Transport In Coastal Aquifers, Yong Peng

Dissertations

Coastal aquifers are distinguished from other aquifers because of tidal effects which cause complicated groundwater flow and contaminant transport phenomena in regions immediately adjacent to the coast. This study is designed to address the significance of tidal influence on contaminant transport by focusing on one-dimensional homogeneous coastal aquifers.

This study formulates a conceptual model and corresponding flow and transport equations, analyzes coastal boundary conditions, solves numerically the transport equation, and uses experiments to verify the numerical results.

Results of numerical and experimental studies conclude that tides can have a significant impact on contaminant transport, especially when under unconfined conditions, subject …

The Testing Of Semiconductor-Based Adsorption Modified Photosensitive Sensors For Their Response To A Volatile Organic Compound, Oxygen, Humidity, And Heating, Roberta Rosty

Dissertations

Two thin-film sensors, composed of different thicknesses (approximately 0.5 microns and 4.5 microns) of a cadmium sulfide layer coated with Rhodamine B fluorescent dye on a glass substrate, were tested for change in photoconductivity due to exposure to different concentrations of gaseous organic molecules in the parts-per-million (ppm) range.

It was theorized that the gaseous organic molecules would adsorb to the dyed semiconductor surface and that some energy would be transferred to the adsorbed analyte rather than to the cadmium sulfide semiconductor layer through the dye, thereby decreasing the photoconductivity of the surface in an amount proportional to the analyte …

Demographic Characteristics And Academic Measures As Predictors Of Success On The American Society For Clinical Pathology (Ascp) Medical Technologist Certification Examination, Marcia Ann Kilsby

Dissertations

Purpose. This study was undertaken to address the utility of demographic characteristics and academic measures as predictors of success for the American Society for Clinical Pathology Board of Registry Medical Technologist Certification Examination (Certification Examination) Total Score and six Subscores and to find predictive models with relevance to an ethnically and racially-diverse student population.

Method. The research population was the graduates of the Andrews University Program for Clinical Laboratory Sciences. The 233 subjects were from 53 different birth countries. The relationships between Certification Examination scores and both demographic characteristics and academic measures were analyzed by chi square, analysis o f …

Suicide Attempt And Characteristics Of Religiously Affiliated Puerto Rican Adolescents And Young Adults, Saúl Rivera

Dissertations

Problem. Recent research has identified several risk factors associated with attempted suicide among the general population. Puerto Ricans, in general, and Puerto Rican Seventh-day Adventists (SDAs), in particular, may face unique challenges that are related to their familial, social, and religious environment that may affect the suicidal attempts among this group. Therefore, this study examined family-related factors, history of being abused, religiosity factors, sexuality factors, gender, substance abuse, age, and socioeconomic status factors among a sample of religiously affiliated Puerto Ricans (73.2% SDAs) living on the island.

Methodology. The data for the study came from the Avance PR study. Avance …

Intuitive Decision Making And Leadership Style Among Healthcare Executives In The United States, Cherie Whiting

Dissertations

The purpose of this two-phased, sequential, exploratory, mixed-methods study was to survey a sample of Fellows in the American College of Healthcare Executives in the United States and then interview selected individuals who scored in the highly intuitive category on the intuition survey to explore how they made intuitive decisions. In the first phase, quantitative research questions addressed the relationship between leadership style and the potential to make intuitive decisions, as well as the relationship and interaction between the potential to make intuitive decisions and age, gender, and size of company. In the second phase, qualitative interviews were used to …

Aims Of Education In The Writings Of Ellen White, Erling Bernhard Snorrason

Dissertations

Problem. Ellen White’s educational philosophy and its application to the aims of education have not been systematically or thoroughly addressed within the parameters and demands of a graduate thesis. The present dissertation explores the aims of education, especially the ultimate aims of education, in the writings of Ellen G. White, one of the founders of the Seventh-day Adventist Church, and could be of value in assessing the present Seventh-day Adventist educational enterprise.

Method. This dissertation is a description and an analysis of Ellen White’s concept of education as revealed by her understanding of the aims of education. It is a …

Youth Ministry And Beliefs And Values Among 10- To 19-Year-Old Students In The Seventh-Day Adventist School System In North America, A. Barry Gane

Dissertations

Problem. A survey of the literature revealed that there was little by way of empirical study on the relationship between youth ministry and attitudes, beliefs, and values held by young people. We empirically tested the anecdotal evidence that youth ministry is effective in the transmission of beliefs and values. The purpose of this study was to ascertain whether Seventh-day Adventist youth ministry in North America makes any difference in the lives of youth in the Seventh-day Adventist school system.

Method. The sample for this study was 10,832 10- to 19-year old students enrolled in SDA schools in 2001. …