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Full-Text Articles in Physical Sciences and Mathematics

Preparation Of Aminoalcohols And Their Application For The Synthesis Of Heterocycles And As Potential Sensors For Nerve Agents, David L. Sellers Dec 2016

Preparation Of Aminoalcohols And Their Application For The Synthesis Of Heterocycles And As Potential Sensors For Nerve Agents, David L. Sellers

Dissertations

Oxazoles and oxazolines are important heterocyclic scaffolds commonly used in pharmaceuticals and optoelectronic materials. Traditionally these heterocyclic compounds are prepared by condensation methodology that suffers from poor reactivity when using electron deficient or sterically crowded reaction partners. Condensation methods also exhibit low tolerance of many functional groups as the reactions typically use strong acids and high temperatures. This dissertation describes an alternate strategy for the formation of these compounds by employing an epoxide opening followed by oxidation to form these heterocyclic compounds.

Epoxide opening reactions with primary aliphatic, allylic, and benzylic amines, aminolysis reactions, often achieve high yields regardless of …


Pedagogical Moves As Characteristics Of One Instructor’S Instrumental Orchestrations With Tinkerplots And The Ti-73 Explorer: A Case Study, James L. Kratky Dec 2016

Pedagogical Moves As Characteristics Of One Instructor’S Instrumental Orchestrations With Tinkerplots And The Ti-73 Explorer: A Case Study, James L. Kratky

Dissertations

Those supporting contemporary reform efforts for mathematics education in the United States have called for increased use of technologies to support student-centered learning of mathematical concepts and skills. There is a need for more research and professional development to support teachers in transitioning their instruction to better meet the goals of such reform efforts.

Instrumental approaches to conceptualizing technology use in mathematics education, arising out of the theoretical and empirical work in France and other European nations, show promise for use to frame studies on school mathematics in the United States. Instrumental genesis is used to describe the bidirectional and …


Crystallography And Magnetism Of Magnetocalorically Important Ni-Mn-X Based Heusler Alloys, Amila S. B. Madiligama Dec 2016

Crystallography And Magnetism Of Magnetocalorically Important Ni-Mn-X Based Heusler Alloys, Amila S. B. Madiligama

Dissertations

Ni-Mn-X Heusler alloys, demonstrating strong coupling between crystalline structure and magnetic state, were studied. They undergo field-induced, first-order transformations from a low symmetry martensite to a high-symmetry austenitic phase around room temperature. The substantial difference between the entropies of the two phases results in a large adiabatic temperature change, called “Giant Magnetocaloric Effect (GMCE)”. Consequently, these alloys are promising refrigerants for near-room temperature cooling systems. This magnetic cooling is an energy-efficient and eco-friendly technology.

Crystalline structures and magnetic states of these alloys, which determine their magnetocaloric performances, highly depend on their composition. To examine new paths to optimize their magnetocaloric …


An R-Matrix, Quantum Defect Theory Approach To The Photoionization Of Molecular Nitrogen, Gaetan L. Vangyseghem Aug 2016

An R-Matrix, Quantum Defect Theory Approach To The Photoionization Of Molecular Nitrogen, Gaetan L. Vangyseghem

Dissertations

No abstract provided.


Some Nonparametric Ordered Restricted Inference Problems In The Context Of A Statistical Education Study, Bradford M. Dykes Aug 2016

Some Nonparametric Ordered Restricted Inference Problems In The Context Of A Statistical Education Study, Bradford M. Dykes

Dissertations

Over the past 10 years, the Department of Statistics at Western Michigan University has developed a question generating system that can be used for creating multiple forms of exams, quizzes and homework for online and face-to-face use. This system can also be used to provide students with a form of instantaneous feedback. With the goal of analyzing how different levels of feedback in an online learning environment impacts students' performance on assignments, this study presents data collected on two semesters of students enrolled in three different meeting types (strictly online, typical face-to-face, and honors face-to-face) of an introductory Statistics course. …


Chromatic Connectivity Of Graphs, Elliot Laforge Jun 2016

Chromatic Connectivity Of Graphs, Elliot Laforge

Dissertations

No abstract provided.


N-Terminal Domains Of Copper Atpases In Plasmodium Falciparum, Dictyostelium Dicsoideum, Human Atp7b And A Chimera Of Atox1 With Metal Binding Domain Four Of Atp7b, Javan Kilango Kisaka Jun 2016

N-Terminal Domains Of Copper Atpases In Plasmodium Falciparum, Dictyostelium Dicsoideum, Human Atp7b And A Chimera Of Atox1 With Metal Binding Domain Four Of Atp7b, Javan Kilango Kisaka

Dissertations

Copper transporting ATPases (Cu-ATPases) are essential for mediating copper uptake, maintaining cellular copper levels and prevention of accumulation of toxic copper. The most studied copper ATPases are the Menkes and Wilson proteins in eukaryotes, CopA and CopB found in bacteria. The precise interaction of the metal binding domains with their copper donor, the association of each metal binding domain within the N-terminal portion of the protein, how they communicate with each other, and the eventual metal ion translocation across the membrane, is little known. The variation in number of the cytosolic metal binding domains may also offer clues on the …


Statistical Methodology For Data With Multiple Limits Of Detection, Robert M. Flikkema Jun 2016

Statistical Methodology For Data With Multiple Limits Of Detection, Robert M. Flikkema

Dissertations

Limitations of instruments used to collect continuous data sometimes lead to obtaining observations lower than a limit of detection. These observations are known as nondetects. They could be zeroes, or positive numbers, but they are too small to be recorded by a measuring device. Nondetects frequently occur in environmental data. Trace amounts of chemicals can exist in soil or groundwater and are undetectable by a machine reading. These observations pose a problem to researchers since the true values are unknown.

Simulations in the literature have led to inconsistent conclusions regarding what estimation technique to use with nondetect data when estimating …


Resolving Classes And Resolvable Spaces In Rational Homotopy Theory, Timothy L. Clark Jun 2016

Resolving Classes And Resolvable Spaces In Rational Homotopy Theory, Timothy L. Clark

Dissertations

A class of topological spaces is called a resolving class if it is closed under weak equivalences and homotopy limits. Letting R(A) denote the smallest resolving class containing a space A, we say X is A-resolvable if X is in R(A), which induces a partial order on spaces. These concepts are dual to the well-studied notions of closed class and cellular space, where the induced partial order is known as the Dror Farjoun Cellular Lattice. Progress has been made toward illuminating the structure of the Cellular Lattice. For example: Chachólski, Parent, and Stanley have shown that it …


Empirical Evaluation Of Different Features Of Design In Confirmatory Factor Analysis, Deyab Almaleki Apr 2016

Empirical Evaluation Of Different Features Of Design In Confirmatory Factor Analysis, Deyab Almaleki

Dissertations

Factor analysis (FA) is the study of variance within a group. Within-subject variance (WSV) is affected by multiple features in a study context, such as: the study experimental design (ED) and sampling design (SD), thus anything that influences or changes variance may affect the conclusions related to FA.

The aim of this study was to provide empirical evaluation of the influence of different aspects of ED and SD on WSV in the context of FA in terms of model precision and model estimate stability. Four Monte Carlo population correlation matrices were hypothesized based on different communality magnitudes (high, moderate, low, …


Bivariate Negative Binomial Hurdle With Random Spatial Effects, Robert Mcnutt Apr 2016

Bivariate Negative Binomial Hurdle With Random Spatial Effects, Robert Mcnutt

Dissertations

Count data with excess zeros widely occur in ecology, epidemiology, marketing, and many other disciplines. Mixture distributions consisting of a point mass at zero and a separate discrete distribution are often employed in regression models to account for excessive zero observations in the data. While Poisson models are very popular for count data, Negative Binomial models provide greater flexibility due to their ability to account for overdispersion.

This research focuses on developing a method for analyzing bivariate count data with excess zeros collected over a lattice. A bivariate Zero-Inflated Negative Binomial Hurdle (ZINBH) regression model with spatial random effects is …