Physical Sciences and Mathematics Commons^™

Microwave-Assisted Synthesis Of Quinoxaline Derivatives, Eric Horsting

Honors Theses

Quinoxaline and its derivatives have been studied extensively for their relevant biological activity and transition metal selectivity. These compounds are commonly used for their antimicrobial, antifungal, antiparasitic activity, and relevance in the treatment of metabolic diseases [6]. More recently, quinoxaline’s ability to inhibit gram-positive bacterial growth has been found especially in oxygen- containing compounds, yielding promising candidates to prevent cancerous tumor growth [5]. The breadth of quinoxaline makes it a valuable tool within the research community However, its synthesis requires complex solvents, extended reaction times, and often produces a low yield. By using a microwave-assisted synthesis, this novel methodology offers …

Isolating And Manipulating Microorganisms Using Ureolysis For Creating Extraterrestrial Microbial Biotechnology Systems, Nina M. Wendel

Honors Theses

The conversion of CO2 into valuable feedstocks, such as high energy sugars would create paradigm shifting technologies for applications on earth and for interplanetary exploration. Microbes and microbe consortia may be one way to accomplish this conversion. Approximately 70% of the Earth’s microorganisms live in the dark marine biosphere (DMB). The DMB, which covers more than two-thirds of the Earth, is known as the most isolated region of the Earth’s largest CO2 sink. Despite its role in reducing CO2 and its vast majority of microorganisms, only about 5% of the sea floor has been explored. Due to the limited knowledge …

Development Of Nucleic Acid Aptamers To Inhibit Bacterial Efflux Pumps, Emilie A. Moses

Honors Theses

Multidrug resistance in bacteria, defined as the ability of a bacterial strain to resist the killing effects of more than one antibiotic, represents a major threat to global healthcare. Every year in the United States, two million people are infected with a multidrug resistant strain of bacteria. According to the Center for Disease Control (CDC), out of those two million people, about 35,000 will die from their infection. Thus, these multidrug resistant diseases are considered by the CDC to be the most dangerous diseases in the world. While multidrug resistance can occur through several different mechanisms, a major contributor to …

A Study On Formal Verification For Javascript Software, Zachary S. Rowland

Honors Theses

Information security is still a major problem for users of websites and hybrid mobile applications. While many apps and websites come with terms of service agreements between the developer and end user, there is no rigorous mechanism in place to ensure that these agreements are being followed. Formal methods can offer greater confidence that these policies are being followed, but there is currently no widely adopted tool that makes formal methods available for average consumers. After studying the current state-of-the-art in JavaScript policy enforcement and verification, this research proposes several new techniques for applying model checking to JavaScript that strikes …

The Tolerance Of Shewanella Woodyi For Electric Potentials And Heavy Metals As Biofilms, Christopher Thomas Mortensen

Honors Theses

Shewanella woodyi is a bioluminescent marine organism that is known to be metal tolerant and modulate the intensity of its luminescence with electrochemical potential. The viability of S. woodyi as a bioreporter for the toxic heavy metal zinc, copper, and silver was analyzed. Biofilms of S. woodyi was grown on marine broth agar plates and then exposed to various concentrations of each metal ion to evaluate biofilm response to the metal ions that were generated from an operating short circuited electrode containing either Zn, Cu, or Ag metal. The ability of the bacteria to tolerate the heavy metals and continue …

Computer-Assisted Graphic Correlation Of Ordovician Conodonts And Graptolites From The Argentine Precordillera And Western Newfoundland Using Constrained Optimization (Conop9), Andrea Marie Bryan

Honors Theses

The correlation of rock units is the foundation of geological research. Correlation is the process of proving two geologic events are time equivalent. Most importantly, it is used to establish time boundaries in the geologic time scale. This paper uses computer assisted graphic correlation (CONOP9) to correlate the ages of graptolites and conodonts from the Ordovician found in rocks from the continent Laurentia, and arranges them in a composite range chart. These two organisms lived in different environments and, therefore, are found in different biofacies. The Argentine Precordillera and the western Newfoundland region are places where these two fossils co-exist …

Tracking Disparate Colony Morphological Trends With Thermus Scotoductus, Matthew P. Leverick

Honors Theses

When plating most mesophilic bacteria, the colony shape, size, and color tends to be uniform when a single strain is present. When plating defined cell densities of T. scotoductus, however, the colonies were not of uniform size and shape while it grew on the surface. In this project, we sought to observe trends in colony morphology (shape and size) changes using the thermophile Thermus scotoductus on nutrient rich agar plates at 60°C. A general planktonic growth curve was also created to help characterize the activity of this bacterium. This project was our first attempt to characterize if this unusual phenomenon …

Analysis And Review Of The Effects Of Bacterial Competition On Efflux Pump Inhibition, Robert Leszcynski

Honors Theses

Multidrug resistant antibacterial strains are a dangerous problem for modern medical professionals. When cells of two different strains are grown together, they must compete with each other for nutrients. This competition can lead to the production of harmful compounds that are toxic to the competing strain. One such compound may be a compound that inhibits the efflux of antibiotics from the cell. When the cells compete with one another, one or both of the cells will produce compounds that are harmful to the competing strain.

Boron Dipyrromethenes: Synthesis And Computational Analysis, Eduardo Rivé Lockwood

Honors Theses

Recently, there has been a growing interest in the boron dipyrromethene (BODIPY, 4,4′- difluoro-4-bora-3a,4a-diaza-s-indacene) compounds. BODIPY compounds have fascinating properties that allow for the absorption and emission of light in the near infrared region of the electromagnetic spectrum. These molecules are highly modifiable making them ideal chemicals for the use of photoelectric energy conversion such as for commercial use in dye sensitized solar cells (DSSCs). It has been previously shown that different meso compounds have only a slight effect on the absorptive capabilities of these BODIPY compounds. We believe that the BODIPY compounds’ lack of planarity is one of the …

Nitrate Contaminant Tracing In Surface And Groundwater In The Great Miami River Watershed: Environmental Isotope Approach, Rachel Kristine Buzeta

Honors Theses

The global population has increased exponentially causing several challenges surrounding sustainability, including greater food production needs. To meet these demands and boost agricultural productivity, more efficient practices and fertilizers are used. Synthetic fertilizers and other nutrient sources have resulted in water quality degradation and pollution. Much of the Great Miami River Watershed’s streams and aquifers in southwestern Ohio are affected by nitrate contaminants originating from anthropogenic sources including synthetic and organic fertilizer used for agriculture, human wastes (domestic, industrial, and municipal wastes), and urbanization. High nitrate concentrations cause ecological disturbances across all trophic levels. Nitrate levels greater than 10 mg/L …

The Number Of Fixed Points Of And-Or Networks With Chain Topology, Lauren Geiser

Honors Theses

Boolean networks are sets of Boolean functions, which are functions that contain Boolean variables and the logical operators AND, OR, and NOT. In the simple case, the variables can be in one of two states—either 1 or 0, which can be interpreted in different ways such as ON or OFF, or TRUE or FALSE, depending on the application. Arranging model systems into Boolean functions, we can study steady states of these networks. This refers to the overall state of the dynamical system given an initial condition and another theoretical condition such as a subsequent point in time. Boolean networks have …

Topology Of Fractals, Amelia Pompilio

Honors Theses

No abstract provided.

Identifying Natural Inhibitors Of Bacterial Efflux Pumps, Marrisa Therriault

Honors Theses

Antibiotic resistance is a constantly progressing epidemic. Many strains of bacteria have developed a resistance to antibiotics, resulting in prolonged sickness and death. Resistance can be to a specific drug (single drug resistance) or to multiple drugs (multi-drug resistance). This resistance can be caused by a tripartite protein pump called an efflux pump that extends through the inner and outer membranes of the bacterium to pump antibiotics from the inside of the cell to the extracellular environment. In E. coli the efflux pump is called AcrAB-TolC. In the efforts to combat this problem, this experiment focuses on the inactivation of …

The Impact Of The 515nm Effect On 1o2 Quenching In Photosynthesis: Model System Studies Using Β-Carotene–Acid Complexes, Lauren A. Hoody

Honors Theses

β-carotene (βC) is an orange pigment present in the photosynthetic reaction center (PRC) of green plants, where it plays a vital role in photosynthesis: It quenches singlet oxygen (1O2 , a toxic oxidizing species generated during photosynthesis) before the 1O2 damages chlorophyll and other components of the PRCs. During photosynthesis, βC temporarily converts from its native orange–450 state to a pink–515 state via the so–called 515nm Effect. Because of the differences between the electronic structures of orange–450 and pink–515, I hypothesize that pink–515 will quench 1O2 less efficiently than orange–450. This hypothesis has not been tested to date because orange–450 …

Probabilistic Modeling Of Student Interactions During A Passing Period At The University Of Dayton, Allyson Pacifico

Honors Theses

The University of Dayton is composed of five colleges and schools: College of Arts and Sciences, School of Law, School of Business Administration, School of Education and Health Sciences, and School of Engineering. The University of Dayton is composed of about 11,000 students on campus who all have distinct class schedules and paths they take between their classes. In this study, I wanted to know the probability of meeting my friends with a different class schedule as I walk between classes. The data consisted of one to two students from each college, except for the School of Law, who documented …

Revising The Geological Time Scale: A Conop9 Graptolite Composite From The Middle Ordovician Rocks Of Newfoundland, Katherine Michel

Honors Theses

The Geological Time Scale is a fundamental tool for geoscientists that is revised and republished every eight years. It is a representation of the geologic record - a system composed of radioisotope dates interpolated into fossil successions that can be used to correlate rocks. The current Geologic Time Scale for the Ordovician Period (GTS 2012) is composed of a sequence of species ranges from a group of fossils called graptolites with interpolated radiometric dates. Building a global geologic time scale requires correlating between different biofacies.

In this thesis I will attempt to combine stratigraphic range data from different kinds of …

The Effects Of Structural Modification Of The Wing Helix Domain Of Pria On Bacterial Dna, Erich Auer

Honors Theses

During a cell’s life it must copy itself or face death. For the cell to form a new copy it must replicate its DNA, this DNA is the blueprint for the essential components of the cell. The replication process does not always go to completion, which is necessary for the cell to survive, so there are mechanisms to keep the replication process running smoothly. In bacteria, PriA is used to restart replication after damage to the DNA. By looking at the structure of PriA we can start to determine how exactly it works with the damaged DNA and restart the …

Preparation, Analysis And Derivatization Of Benzotris(Thiazole) Triamine, Jonathan Patrick Peter Alessi

Honors Theses

Multiple fields are areas of active research where organic materials hold considerable promise, such as thermoelectrics or photovoltaics. In an effort to design and prepare a new system which would exhibit a set of promising features such as high thermal stability, high degree of planarity, rigid skeleton and strong electron accepting properties, we have undertaken the preparation and characterization of benzotrithiazole and its derivatives. Our work has led to a reproducible and scalable protocol for the generation of one particular structure: benzo[1,2-d:3,4-d':5,6-d"]tris(thiazole)-2,5,8-triamine. We have also conducted further attempts to functionalize this structure, leading to other derivatives of the target compound.

Synthesis Of Bis(Quinoxalino) Ligand For The Removal Of Transition Metal Contamination, Alexander J. Farmer

Honors Theses

Transition metal contamination is a constant concern both in the environment and in chemical reaction mixtures. One proposed solution, is the use of peraza-crown macrocycles to selectively bind and remove transition metals. The aim of our project is to determine the novel synthesis of bis(quinoxalino) peraza-crown macrocycles for use as ligands to bind to transition metals. Our proposed molecules incorporate the rigid quinoxaline subunit into an aza-crown macrocycle which can improve binding properties. The synthesis route is novel and overcomes several limitations of the existing methods of aza-crown macrocycle preparation. We have designed the synthesis in such a way that …

Extending Uniqueness Implies Existence Results To Fractional Differential Equations, Tyler Masthay

Honors Theses

In 1967, Andrzej Lasota and Zdzisław Opial proved that under sufficient conditions, uniqueness of solutions for boundary value problems for a second-order ordinary differential equation implies their existence. Lloyd Jackson and Keith Schrader then proved an extension of this result for boundary value problems of third order. In proving the third-order case, this compactness theorem is applied as a key part of the proof. It states that under sufficient conditions, uniform boundedness of a sequence of solutions on a compact domain implies existence of a subsequence which converges uniformly with respect to its zeroth, first, and second derivatives. We present …

Star Decompositions Of The Complete Split Graph, Adam C. Volk

Honors Theses

A graph is a discrete mathematical structure that consists of a set of vertices and a set of edges between pairs of vertices. A problem of interest in graph theory is that of graph decomposition, partitioning the set of edges into disjoint sets, producing subgraphs which are isomorphic to each other. Here we consider the problem of decomposing a class of graphs called complete split graphs into stars of a fixed size. We present conditions for the decomposition as well as an algorithm for the decomposition when it is possible.

Global And Regional Chitinozoan Biodiversity Dynamics In The Ordovician: Relationships To Sea-Level, Carbon Cycling And Tectonics, Jordan Watson

Honors Theses

Fossil species provide extensive information about the past history of life on Earth. This thesis focuses on the global and regional biodiversity dynamics of the extinct fossil group Chitinozoa, and analyzes the impact and influences of sea-level, global carbon cycling and tectonics on their biodiversity. Biodiversity curves were generated from three different paleo-continents, Laurentia, Baltica, and Gondwana using the automated graphic correlation computer program CONOP9. Traditional methods of biodiversity analysis count fossil taxa in individual intervals of geologic time. The results of these methods are highly dependent upon interval length and the relationship of taxon range to interval boundaries. CONOP9 …

Results On Some Generalizations Of Interval Graphs, Jonathan David Ashbrock

Honors Theses

An interval graph is the intersection graph of a family of intervals on the real line. Interval graphs are a well-studied class of graphs. Path graphs are a generalization of interval graphs and are defined to be the intersection graphs of a family of paths in a tree. In this thesis, we study path graphs which are representable in a subdivided K_{1, 3}. Our main results are a characterization theorem and a polynomial time algorithm for recognition of this class of graphs. The second section of this thesis provides a bound for a graph parameter, the boxicity of …

Domain Representability And Topological Completeness, Matthew D. Devilbiss

Honors Theses

Topological completeness properties seek to generalize the definition of complete metric space to the context of topologies. Chapter 1 gives an overview of some of these properties. Chapter 2 introduces domain theory, a field originally intended for use in theoretical computer science. Finally, Chapter 3 examines how this computer-scientific notion can be employed in the study of topological completeness in the form of domain representability. The connections between domain representability and other topological completeness properties are subsequently examined.

Synthesis Of Phosphorus-Based Hemiacetals For Potential Flame Retardants, Sara Alakkad

Honors Theses

Flame retardants which contain a phosphorus moiety attached to a carbohydrate backbone were developed. To synthesize the flame retardants, carbohydrates and polyols were used as the starting materials which occur in nature and are environmentally and toxicologically safe materials. The two target structures include one with a triose substructure and one with a pentose substructure. For both situations, however, multiple steps were taken for the synthesis of the flame retardant, as the carbohydrate needed to be generated into its protected form. The protected carbohydrate then interacted with a dialkyl phosphite, resulting in a phosphorous hemiacetal. This hemiacetal was then deprotected …

Exploration Of Protein-Protein Interactions Involving Deinococcus Radiodurans Pria, Dnab And Ssb, Christopher S. Morrow

Honors Theses

Deinococcus radiodurans is a species of bacteria that has sparked a lot of interest since its discovery due to its incredible resistance to ionizing radiation. When exposed to ionizing radiation the genome of D. radiodurans will sustain over one hundred double stranded breaks. D. radiodurans demonstrates the ability to repair its genome and restart replication after sustaining, typically lethal, DNA damage. This project examined the mechanism of replication restart in D. radiodurans by investigating primosome protein PriA interacting with replicative helicase DnaB and single stranded binding protein. Many different types of gel electrophoresis were employed to investigate potential protein complex …

Root Cover Pebbling On Graphs, Claire A. Sonneborn

Honors Theses

Consider a graph, G, with pebbles on its vertices. A pebbling move is defined to be the removal of two pebbles from one vertex and the addition of one pebble to an adjacent vertex. The cover pebbling number of a graph, γ(G), is the minimum number of pebbles such that, given any configuration of γ(G) pebbles on the vertices of G, pebbling moves can be used to place one pebble on each vertex of G. We define the root vertex of a graph and fix an initial configuration of pebbles on G where we place all pebbles on the root …

Chitinozoan Biodiversity In The Ordovician Of Gondwana: An Interval-Free Approach Using The Quantitative Stratigraphic Correlation Program Conop9, Rachel Sales

Honors Theses

The purpose of this study is to examine the biodiversity patterns of a group of fossil organisms called chitinozoans. Chitinozoans are organic-walled, planktonic microfossils that first appear in the Early Ordovician Period (488 million years ago) and diversify rapidly through the Paleozoic Era. The Ordovician Period was a time of great global climate change, and by studying this group of fossil plankton, we hope to better understand how modern plankton, which are the base of the marine food chain, might respond to climate change. We used a method called constrained optimization (CONOP9) to construct a composite range chart of 152 …

Synthesis Of Potential Phosphorus-Nitrogen Containing Flame Retardants, Colin Kloock

Honors Theses

Production of extremely efficient flame retardants is ideal because, in many instances, the amount of flame retardants that are added to pre-production to the mixture are so large that they can have an effect on the physical properties of the material. In addition, these types of polymers, when added during production, are homogenously mixed throughout the mixture which means not only uniform distribution and therefore function, but a less concentration of the retardants need to be used. Using Phosphorus-Nitrogen containing flame retardants in mixtures can have two means by which they function. First is the ability of P-N compounds to …

Kinetic Characterization Of B-Carotene In N-Hexane At Various Oxygen Concentrations, Katelyn Mary Arnold

Honors Theses

We have characterized the photo – degradation of ẞC in oxygenated and deoxygenated n–hexane solvent and in the solid phase using broadband (BB; λ ≥ 200 nm) and 313 nm filtered output of a 100 W Hg Arc lamp. Oxygen concentrations of 0, 10, 20, and 100% were used in the solution phase studies. ẞC(s) did not photo – degrade upon exposure to BB light under air atmospheres; the mass and appearance of the samples, TLC chromatograms, and the absorption spectra were all identical pre- and post-irradiation. In the solution phase, the order of the photo – degradation with respect …