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Exploring Autism Prediction Through Logistic Regression Analysis With Corrections For Rare Events Data, Jennifer Hunter
Exploring Autism Prediction Through Logistic Regression Analysis With Corrections For Rare Events Data, Jennifer Hunter
Electronic Theses and Dissertations
The study of rare events data in which observations of non-event outcomes far outnumber event outcomes makes inference under these circumstances quite difficult. Ideally, for a binary dependent variable, one would like sample data to contain enough observations from both outcome categories. With rare events data, however, this is usually impossible and/or costly to achieve with random sampling. This exploratory research aims to find a set of potential predictors that could be used to quantify a person's risk for developing autism spectrum disorder. A more efficient data collection strategy will be employed that allows for a smaller sample size of …
Monoamine Transporter Photoaffinity Ligands Based On Methylphenidate And Citalopram: Rational Design, Chemical Synthesis, And Biochemical Application, Nageswari Yarravarapu
Monoamine Transporter Photoaffinity Ligands Based On Methylphenidate And Citalopram: Rational Design, Chemical Synthesis, And Biochemical Application, Nageswari Yarravarapu
Electronic Theses and Dissertations
Monoamine transporters (MATs) are a family of proteins that include the dopamine transporter (DAT), serotonin transporter (SERT), and norepinephrine transporter (NET). Specifically, dysregulation of MAT function is associated with a host of disease states including drug abuse, major depressive disorder, and anxiety. Additionally, several drugs acting as MAT inhibitors are clinically available to treat multiple disorders. However, details regarding the transport inhibition mechanism created by these drugs, as well as their discrete ligand-binding pockets within their target MAT proteins, remains poorly understood. This knowledge gap in turn hinders rational development of novel therapeutics for numerous MAT-associated disorders. The objective of …
Development Of Extraction Method For Persistent Organic Pollutants In Water And Dietary Supplement Using Stir Bar Sorptive Extraction And Isotope Dilution Mass Spectrometry, Weier Hao
Electronic Theses and Dissertations
Persistent organic pollutants (POPs) in drinking water and dietary supplements can be sources of xenobiotic pollutants in human body and cause detrimental impacts on human health. In this study, an accurate, precise, sensitive, reproducible, and green method was developed to quantify POPs in water and dietary supplements using stir bar sorptive extraction- gas chromatography- mass spectrometry and isotope dilution mass spectrometry. Different analytical parameters were tested for method optimization. Based on efficiency as well as recovery of the analytes, stirring at room temperature for one hour with water and methanol as solvent was selected as the optimal method. After validation, …
The Effects Of Molecular Chaperones On Tau Fibril Assembly, Ahmed Omran
The Effects Of Molecular Chaperones On Tau Fibril Assembly, Ahmed Omran
Electronic Theses and Dissertations
The accumulation of microtubule-associated protein tau into fibrillar aggregates is the hallmark of Alzheimer’s disease and other neurodegenerative disorders, collectively referred to as tauopathies. Fibrils can propagate from one cell to the next and spread throughout the brain. However, a study shows that only small aggregates can be taken up by cultured neuronal cells. The mechanisms that lead to the breakage of fibrils into smaller fragments remain unknown. In yeast, the AAA+ chaperone HSP104 processes the reactivation of protein aggregates and is responsible for fragmentation of fibrils. This study focused on investigating the effects of molecular chaperones on tau fibrils …
Behrens-Fisher Analogs For Discrete And Survival Data, S.M. Khurshid Alam
Behrens-Fisher Analogs For Discrete And Survival Data, S.M. Khurshid Alam
Electronic Theses and Dissertations
Discrete data often exhibit variation greater or smaller than predicted by a simple model. Negative binomial distribution and beta-binomial distribution are popular and widely used to accommodate the extra-Poisson and extra-binomial variations respectively in analyzing discrete data. Weibull distribution is one of the most popular distributions in survival data analysis. Often both discrete and survival data appear in groups and it may be of interest to compare certain characteristics of two groups of such data. The purpose of this dissertation is to deal with Behrens-Fisher analogs for data that follow negative binomial, beta-binomial and Weibull distributions. We first develop six …
Representations Of Banach Algebras Subordinate To Topologically Introverted Subpaces, Julan Al-Yassin
Representations Of Banach Algebras Subordinate To Topologically Introverted Subpaces, Julan Al-Yassin
Electronic Theses and Dissertations
We show the existence of a natural bijection between continuous representations of a Banach algebra A on a reflexive Banach space Y subordinate to a topologically introverted subspace X of A * , and normal representations of X * on Y . We define the spaces ap(A) and wap(A) and study some of their properties. We show that if A has a bounded approximate identity, then a functional on A is in wap(A) if and only if it is a coordinate function of a continuous representation of A on a reflexive Banach space. We prove that whenever A has a …
Modern Applications Of Novel Electroless Plating Techniques, Robert Andrew Petro
Modern Applications Of Novel Electroless Plating Techniques, Robert Andrew Petro
Electronic Theses and Dissertations
This dissertation is composed of three distinct but closely related topics on the electrochemical metallization of substrates. The first topic solves the longstanding problem of galvanic corrosion in connection with exploiting the advantageous properties of magnesium {Mg} alloys and is of vital interest to the automotive and aerospace sectors. The second topic provides a new approach to the selective electroless metallization of silicon {Si} in connection with solar cells and other electronic devices. The third topic details a novel method of metal thin film formation using wet chemistry techniques which allow for the deposition of alternating metal layers of different …
Optimal Inference Methods In Linear Models With Change-Points, Fuqi Chen
Optimal Inference Methods In Linear Models With Change-Points, Fuqi Chen
Electronic Theses and Dissertations
In this dissertation, we consider an estimation problem of the regression coefficients in both multiple regression model and multivariate multiple regression model with several unknown change-points. More precisely, we consider the cases where the target parameters (vectors or matrices) are suspected to satisfy some restrictions. In particular, we generalize in four ways, some recent statistical methods in the literatures. First, we relax some assumptions about the dependance structure of the noise and the regressors given in recent literature. Namely, in this dissertation, the dependance structure is as weak as that of an L 2 -mixingale arrays of size -1/2. Second, …
Novel Coordination Cages From T-Shaped Ligands, Ismail Khalafalla Elguraish
Novel Coordination Cages From T-Shaped Ligands, Ismail Khalafalla Elguraish
Electronic Theses and Dissertations
The coordination bond is very useful for supramolecular chemists because of its directionality and reversibility which lead to stable compounds. This thesis describes the synthesis and characterization of new right-angled benzimidazole-based pyridyl ligands and the resulting assemblies that are formed when these ligands were combined with a cis -protected platinum(II) complex. Chapter one gives a brief introduction about how coordination chemistry interfaces with supramolecular chemistry by utilizing coordination bonding in self-assemblies. Chapter two describes the preparation and characterization of new T-shaped bipyridine ligands with a benzimidazole core and the surprising folded tetramers resulted from the combination of these ligands with …
The Development Of Polymer-Coated Electrodes For Chemical Detection, Xuefeng Hu
The Development Of Polymer-Coated Electrodes For Chemical Detection, Xuefeng Hu
Electronic Theses and Dissertations
This research focuses on the development of simple and cost effective approaches for making electrochemical sensors with a great sensitivity and selectivity. As an economic and abundant starting material, organic substrates were investigated to making conductive polymers that showed promising electrocatalytic activities. Firstly, a poly(4-bromoaniline) film was successfully synthesized on a gold electrode and the porous film which was made up of nano-ribbons on the Au electrode was used for the recognition of amino acids enantiomers. Secondly, different halogen ions were introduced to manifest the properties of the synthesized polymers. The results show that bromide ions have significantly inhibited the …
Computational Studies Into Iron-Based Biocatalysis, Rami Gherib
Computational Studies Into Iron-Based Biocatalysis, Rami Gherib
Electronic Theses and Dissertations
Iron-containing enzymes are ubiquitous in nature and play several key roles in living organisms. Unfortunately, like many other types of enzymes, their catalytic mechanisms are often elusive. The work presented herein investigates computationally the catalytic processes of three iron-containing enzymes: glycerophosphosdiesterase from Enterobacter aerogenes (GpdQ), coral allene oxide synthase (cAOS) and S-ribosylhomocysteinase (LuxS). While some were investigated primarily using density functional theory (DFT), others used quantum mechanics/molecular mechanics (QM/MM) and molecular dynamics (MD) simulations in a complementary fashion.
Computational Insights Into The Accuracy And Editing Of Aminoacyl Trna Synthetases, Grant B. Fortowsky
Computational Insights Into The Accuracy And Editing Of Aminoacyl Trna Synthetases, Grant B. Fortowsky
Electronic Theses and Dissertations
Proteins are ubiquitous in nature, carrying out many of life's functions. However, for these biomolecules to function correctly they must be accurately synthesized. The task of ensuring the desired accuracy is achieved falls to Aminoacyl tRNA Synthetases (aaRS). These enzymes catalyze the activation and transfer of amino acids to tRNA. In addition to carrying out these reactions, they also edit against the incorporation of incorrect amino acids. Within this thesis the many facets of aaRS editing and accuracy are examined in detail. In particular, the editing mechanism of Hcy and Hse in MetRS is elucidated in detail. These results allow …
Plasmon-Enhanced Raman And Fluorescence Spectroscopy With Gold And Silver Nanoparticles, Ariel Rodrigo Guerrero Hernandez
Plasmon-Enhanced Raman And Fluorescence Spectroscopy With Gold And Silver Nanoparticles, Ariel Rodrigo Guerrero Hernandez
Electronic Theses and Dissertations
This thesis contains five major contributions to the field of plasmon-enhanced spectroscopy. We start with the report of a unique SERS study of the amino acid hydroxyproline and a deuterated analogue. Later, we move on to the exploration of a major new research path known as shell-isolated nanoparticle-enhanced fluorescence (SHINEF), consisting in the application of silica-shelled noble metal nanoparticles to achieve surface-enhanced fluorescence. The proof of concept of this technique is explained in one chapter. The two following chapters are devoted to the exploration of the plasmonic properties of SHINEF: spectral profile modification showing the close relationship between the observed …
Development And Optimization Of Thermographic Techniques For Non-Destructive Evaluation Of Multilayered Structures, Dmitry J. Gavrilov
Development And Optimization Of Thermographic Techniques For Non-Destructive Evaluation Of Multilayered Structures, Dmitry J. Gavrilov
Electronic Theses and Dissertations
Quality control of modern materials is of the utmost importance in science and industry. Methods for nondestructive evaluation of material properties and the presence of defects are numerous. They differ in terms of their sensitivity and applicability in various conditions, and they provide different kinds of data such as the speed of sound in the material, its hardness, radiation absorption, etc. Based on measured characteristics an analyst makes a decision on the material studied. This work addresses a class of methods known as active thermographic analysis. Thermography analyzes the temperature of the surface of the sample under different external conditions. …
High Precision Three-Body Variational Method For Critical Nuclear Charge, Michael A. Busuttil
High Precision Three-Body Variational Method For Critical Nuclear Charge, Michael A. Busuttil
Electronic Theses and Dissertations
For an atom there exists a critical nuclear charge Z c that is just sufficient to bind the nucleus and its electrons into a stable configuration. A study of the critical charge for two-electron atoms is presented with the purpose of improving accuracy for Z c . To this end, high precision techniques involving the variational method with multiple basis sets in Hylleraas coordinates are employed. The method is particularly well adapted to the case where one electron is strongly bound and the other is at the limit of becoming unbound. The results are analysed in terms of fractional powers …
Metal Organic Rotaxane Polyhedra (Morps), Elizabeth Viljoen
Metal Organic Rotaxane Polyhedra (Morps), Elizabeth Viljoen
Electronic Theses and Dissertations
This thesis presents the design and synthesis of [2]pseudorotaxane and [2]rotaxane ligands and their incorporation into Metal Organic Polygons to form Metal Organic Rotaxane Polygons. Chapter 1 introduces the concepts of supramolecular chemistry and coordination-driven self-assembly, as well as interpenetrated and interlocked molecules and discrete self-assembled architectures with definitions and representative examples from the literature. Chapter 2 presents the incorporation of the bis(pyridinium)ethane/24-crown-8 macrocycle recognition motif into molecular squares and molecular necklaces. It describes the synthesis as well as characterization by means of 1D 1 H, 13 C, and 31 P NMR of a series of molecular polygons incorporating a …
New Materials, Methods, And Molecules For Microelectronic And Molecular Electronic Devices, Michael Stephen Miller
New Materials, Methods, And Molecules For Microelectronic And Molecular Electronic Devices, Michael Stephen Miller
Electronic Theses and Dissertations
This dissertation reports a variety of new methods and materials for the fabrication of electronic devices. Particular emphasis is placed on low-cost, solution based methods for flexible electronic device fabrication, and new substrates and molecules for molecular electronic tunnel junctions. Chapter 2 reports a low-cost, solution based method for depositing patterned metal circuitry onto a variety of flexible polymer substrates. Microcontact printing an aluminum (III) porphyrin complex activates selected areas of an oxidized polymer substrate to electroless copper metallization. Chapter 3 reports a new transparent conductive electrode for use in optoelectronic devices. A highly conductive, transparent silver nanowire network is …
Synthesis Of Metallic Nanostructures For Applications In Ultrasensitive Detection, Yun Zhang
Synthesis Of Metallic Nanostructures For Applications In Ultrasensitive Detection, Yun Zhang
Electronic Theses and Dissertations
The plasmonic enhancement of fluorescence and scattering is built up by the local field created in nanostructures of silver and gold sustaining localized surface plasmon resonances (LSPR). The plasmon properties in metallic nanostructures depend on their shapes, sizes and the dielectric properties of the metal and the environment. Therefore, the fabrication of nanostructures with controlled plasmon properties is at the heart of practical applications. One of the main objectives of the research work presented in this thesis was to develop reproducible protocols for coating the silver colloids to form shell-isolated nanoparticles, and extend the work to different shapes. The fabricated …
Failure Mechanism Of Coated Biomaterials Under High Impact-Sliding Contact Stresses, Ying Chen
Failure Mechanism Of Coated Biomaterials Under High Impact-Sliding Contact Stresses, Ying Chen
Electronic Theses and Dissertations
This study uses a newly developed testing method-- inclined cyclic impact-sliding test to investigate the failure behaviors of different types of biomaterials, (SS316L, Ti6Al4V and CoCr) coated by different coatings (TiN, DLC and PEO), under extremely high dynamic contact stress conditions. This test method can simulate the combined impact and sliding/rolling loading conditions, which is very practical in many aspects of commercial usages. During the tests, fatigue cracking, chipping, peeling and material transferring were observed in damaged area. This research is mainly focused on the failure behaviors of load-bearing materials which cyclic impacting and sliding are always involved. This purpose …
Ultrasonic Real-Time Quality Monitoring Of Aluminum Spot Weld Process, Waldo Josue Perez Regalado
Ultrasonic Real-Time Quality Monitoring Of Aluminum Spot Weld Process, Waldo Josue Perez Regalado
Electronic Theses and Dissertations
The real-time ultrasonic spot weld monitoring system, introduced by our research group, has been designed for the unsupervised quality characterization of the spot welding process. It comprises the ultrasonic transducer (probe) built into one of the welding electrodes and an electronics hardware unit which gathers information from the transducer, performs real-time weld quality characterization and communicates with the robot programmable logic controller (PLC). The system has been fully developed for the inspection of spot welds manufactured in steel alloys, and has been mainly applied in the automotive industry. In recent years, a variety of materials have been introduced to the …
Vocal Behaviour, Geographic Variation, And The Evolution Of Song In Troglodytes Wrens, Jose Roberto Sosa Lopez
Vocal Behaviour, Geographic Variation, And The Evolution Of Song In Troglodytes Wrens, Jose Roberto Sosa Lopez
Electronic Theses and Dissertations
Animal acoustic signals are important for mate attraction, resource defense, and species recognition. When vocalizations diverge between closely related groups they can play a key role in speciation. Therefore it is important for biologists to describe the vocalizations of wild animals, to document geographic differences in acoustic signals, and to evaluate the relationship between acoustic variation, genetic variation, and ecological variation. In this dissertation, I study the songs of New World wrens in the genus Troglodytes , small territorial songbirds distributed throughout the Americas, including several oceanic islands, that are well known for their loud, complex songs. I conducted observational …
On The Divided Power Structures In Super-Rings, Reginald F. Robson
On The Divided Power Structures In Super-Rings, Reginald F. Robson
Electronic Theses and Dissertations
Given a super-commutative ring A=A 0 direct summed with A 1 , does (A 0 ,A 1 A 1 ) always have a divided power structure? We give an example proving the answer is no. There exists a super-commutative ring SR=SR 0 direct summed with SR 1 with no divided power structure possible on (SR 0 ,SR 1 SR 1 ). Also, we study super divided power structures and the properties they force onto divided power structures on the even part of a ring-ideal pair. We show that there can exist a divided power structure on the even part that …
Bioacoustic Monitoring Of Nocturnal Songbird Migration In A Southern Great Lakes Ecosystem, Claire Elizabaeth Sanders
Bioacoustic Monitoring Of Nocturnal Songbird Migration In A Southern Great Lakes Ecosystem, Claire Elizabaeth Sanders
Electronic Theses and Dissertations
Many species of birds produce short vocalizations during nocturnal migration. My thesis uses bioacoustic monitoring of these night flight calls to study bird migration through a southern Great Lakes ecosystem. I deployed recording devices around western Lake Erie during spring and fall migrations. Analysis of thousands of hours of recordings revealed that night flight calls accurately predicted both the magnitude of migration, as well as the timing of migrant passage, as assessed by banding. The first arrival dates for 48 species of migratory birds were significantly earlier on Pelee Island than on mainland Ontario in the spring. More flight calls …
Automated Classification Of Medical Percussion Signals For The Diagnosis Of Pulmonary Injuries, Bhuiyan Md Moinuddin
Automated Classification Of Medical Percussion Signals For The Diagnosis Of Pulmonary Injuries, Bhuiyan Md Moinuddin
Electronic Theses and Dissertations
Used for centuries in the clinical practice, audible percussion is a method of eliciting sounds by areas of the human body either by finger tips or by a percussion hammer. Despite its advantages, pulmonary diagnostics by percussion is still highly subjective, depends on the physician's skills, and requires quiet surroundings. Automation of this well-established technique could help amplify its existing merits while removing the above drawbacks. In this study, an attempt is made to automatically decompose clinical percussion signals into a sum of Exponentially Damped Sinusoids (EDS) using Matrix Pencil Method, which in this case form a more natural basis …
Bayesian Spatial Additive Hazard Model, Alexander Chernoukhov
Bayesian Spatial Additive Hazard Model, Alexander Chernoukhov
Electronic Theses and Dissertations
This thesis will be dealing with the problem of Bayesian estimation in additive survival data models accounting for spatial dependencies. We consider the Aalen's additive hazards model in which baseline hazard function, the regression coecients as well as the covariates are all allowed to be time varying processes. We incorporate in this model an extra random vector of frailties accounting for spatial variations among the observations. Consequently, we propose a Bayesian approach to solving the inference problem for such spatial frailty model by assuming piece-wise constant structure on all timevarying functions in the model and hence, imposing appropriately chosen priors …
Cooperative Functions Of Duetting Behaviour In Tropical Wrens, Kristin Ashley Kovach
Cooperative Functions Of Duetting Behaviour In Tropical Wrens, Kristin Ashley Kovach
Electronic Theses and Dissertations
Vocal duets occur when two breeding partners coordinate their songs into a joint display. Duetting serves functions both within and between pairs, and functionality is often context dependent. I explore the function of temporal coordination of male and female songs into duets, testing the hypothesis that coordinated duets are more threatening territorial signals than poorly coordinated duets or solos in three closely related species of wren. Results indicate that birds respond with similar levels of physical aggression to all three levels of coordination; however, they sing more duets in response to both categories of duets. I also explore duets and …
Self-Assembled Monolayers Of Dithiophosphinic Acids On Gold, Ronan Roca San Juan
Self-Assembled Monolayers Of Dithiophosphinic Acids On Gold, Ronan Roca San Juan
Electronic Theses and Dissertations
This dissertation reports the synthesis of derivatives of dithiophosphinic acids (R 1 R 2 DTPAs), and the formation and characterization of DTPA SAMs on gold to build a knowledge base on their nature of binding, organization of the alkyl chains and electrochemical barrier properties. The binding of DTPA molecules on gold depends on the morphology of the gold film: They bind in a mixed monodentate and bidentate modes on standard as-deposited (As-Dep) gold, while they fully chelate on smoother template-stripped (TS) gold. Chapter 2 focuses on van der Waals interactions of various alkyl chain lengths of symmetrical R 2 DTPA …
Investigation Of In-Vehicle Speech Intelligibility Metrics For Normal Hearing And Hearing Impaired Listeners, Nikolina N. Samardzic
Investigation Of In-Vehicle Speech Intelligibility Metrics For Normal Hearing And Hearing Impaired Listeners, Nikolina N. Samardzic
Electronic Theses and Dissertations
The effectiveness of in-vehicle speech communication can be a good indicator of the perception of the overall vehicle quality and customer satisfaction. Currently available speech intelligibility metrics do not account in their procedures for essential parameters needed for a complete and accurate evaluation of in-vehicle speech intelligibility. These include the directivity and the distance of the talker with respect to the listener, binaural listening, hearing profile of the listener, vocal effort, and multisensory hearing. In the first part of this research the effectiveness of in-vehicle application of these metrics is investigated in a series of studies to reveal their shortcomings, …
Radiative Decay Rates Of Metastable Triplet Helium And Heliumlike Ions, Lauren L. Moffatt
Radiative Decay Rates Of Metastable Triplet Helium And Heliumlike Ions, Lauren L. Moffatt
Electronic Theses and Dissertations
The metastable 1 s 2 s 3 S 1 state of helium is the longest-lived neutral atomic state with a lifetime of 7859 seconds. This property has important astrophysical applications in the determination of temperature and density conditions in low density sources such as planetary nebulae. This lifetime is determined by single photon relativistic magnetic dipole (M1) transition rates and is evaluated numerically using large basis size variational Hylleraas wave functions for all the heliumlike ions through the isoelectronic sequence up to Ar +16 . The coefficients of a Z -1 expansion, based on the results from the variational calculation, …
New Directions For Solid-State Nmr Of Insensitive Nuclei: Applications To Metal Nuclei In Inorganic Materials, Bryan Lucier
New Directions For Solid-State Nmr Of Insensitive Nuclei: Applications To Metal Nuclei In Inorganic Materials, Bryan Lucier
Electronic Theses and Dissertations
This thesis is largely devoted to solid-state NMR (SSNMR) studies of insensitive nuclei, which are challenging to study via conventional NMR experiments due to their low natural abundances, low gyromagnetic ratios, and/or anisotropically broadened powder patterns. SSNMR experiments on insensitive nuclei such as 195 Pt, 89 Y, 65 Cu, 35 Cl, and 14 N hold much promise for elucidation of structure and bonding within inorganic and organometallic systems. Herein, I describe the use of novel NMR pulse sequences and acquisition methodologies, in combination with X-ray diffraction (XRD) techniques and quantum chemical calcuations of NMR interaction tensors, for this purpose. This …