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Full-Text Articles in Other Physical Sciences and Mathematics

Computational Study Of Radical Cation Rearrangements, Mi'kayla D. Word Jan 2021

Computational Study Of Radical Cation Rearrangements, Mi'kayla D. Word

Theses and Dissertations

A radical cation is a molecule that has one unpaired electron that holds a positive charge. The unpaired electron within a radical cation causes the molecule to be reactive. The high reactivity of these species allows for radical cations to be commonly studied experimentally using mass spectrometry and other multi-mass imaging techniques. However, these methods often cannot resolve the reaction mechanisms for these fast reactions. Specifically, radical cation rearrangement mechanisms are particularly unresolved within experiments. For this reason, radical cation rearrangements are computationally investigated to explain complex reaction pathways for processes to understand reactions leading to the initiation of detonation …


Evaluation Of Five Methods To Develop Latent Prints On Thermal Paper, Jenna Pregent Jan 2021

Evaluation Of Five Methods To Develop Latent Prints On Thermal Paper, Jenna Pregent

Master of Science in Forensic Science Directed Research Projects

Forensic latent fingerprint laboratories determine the proper techniques for fingerprint visualization based on the substrates upon which they are deposited. Typical forensic analysis of thermal paper evidence involves the application of ninhydrin and/or 1,2-indanedione dissolved in a polar solvent. However, polar solvents create an undesirable reaction with the thermal paper’s internal properties and often lead to discoloration of the evidence. When this occurs, not only are the fingerprints less likely to be visible due to the loss of contrast, but the evidentiary print on the receipt may be lost entirely. This research sought to compare five development methods to determine …


Identification Of Compounds Causing Cellular Autofluorescence In Touch Samples, Elora C. Wall Jan 2021

Identification Of Compounds Causing Cellular Autofluorescence In Touch Samples, Elora C. Wall

Master of Science in Forensic Science Directed Research Projects

As DNA analysis has advanced and produced tests with higher sensitivities, attention has turned toward obtaining DNA profiles from cells left with fingermarks. Recent studies have reported that cells deposited within fingermarks can exhibit differences in autofluorescence emission in the ‘red’ region of the visible spectrum (e.g., between 650-670 nm), which can be used to differentiate contributor cell population and separate them before DNA profiles. Interestingly, this emission was not consistent to the individual day-to-day and likely not a genetically-controlled attribute of the contributor. Instead, this emission signature results from extended exposure of the skin to certain materials such as …


Modeling Vegetation Effects On Barrier Island Evolution, Eric W. Schoen Jan 2021

Modeling Vegetation Effects On Barrier Island Evolution, Eric W. Schoen

Theses and Dissertations

Barrier islands play a significant role in protecting coastlines and harboring coastal habitats. In an effort to study and better understand the evolution of barrier island systems, a cellular model capturing various meteorological and environmental processes is proposed. Erosion due to wind, gravity, and marine processes are coupled with plant population effects. We demonstrate the inhibition of plant cover on sediment mobility, island migration, and erosion in the presence of sea level rise.


Modeling The Evolution Of Barrier Islands, Greg Robson Jan 2020

Modeling The Evolution Of Barrier Islands, Greg Robson

Theses and Dissertations

Barrier islands form off the shore of many coastal areas and serve as the first line of defense, protecting littoral communities against storms. To study the effects that climate change has on barrier islands, we use a cellular model of wind erosion, surface dynamics, beach dynamics, marsh dynamics, and vegetation development. We will show the inhibition of movement when vegetation is present.


Kings In The Direct Product Of Digraphs, Morgan Norge Jan 2019

Kings In The Direct Product Of Digraphs, Morgan Norge

Theses and Dissertations

A k-king in a digraph D is a vertex that can reach every other vertex in D by a directed path of length at most k. A king is a vertex that is a k-king for some k. We will look at kings in the direct product of digraphs and characterize a relationship between kings in the product and kings in the factors. This is a continuation of a project in which a similar characterization is found for the cartesian product of digraphs, the strong product of digraphs, and the lexicographic product of digraphs.


Identification Of “Kratom” (Mitragyna Speciosa) Alkaloids In Commercially Available Products, Julia Grzymkowski, Michelle R. Peace, Justin Poklis Jan 2017

Identification Of “Kratom” (Mitragyna Speciosa) Alkaloids In Commercially Available Products, Julia Grzymkowski, Michelle R. Peace, Justin Poklis

Undergraduate Research Posters

“Kratom” is the common name for the botanical mitragyna speciosa. It is a tree native to Southeast Asia in which leaves contain the psychoactive alkaloids mitragynine and 7-hydroxymitragynine. Kratom is often ingested as teas, chewed, or smoked. It acts as a stimulant in small doses and as an opioid in large doses. Overdoses can result in vomiting, seizures, and death. Recently the Drug Enforcement Agency (DEA) placed Kratom on Schedule 1, but, due to public outcry, it was almost immediately removed.

Eleven kratom based products were obtained from various tobacco shops, “headshops” and via the internet including: Choice brand …


Forensic Chemical Analysis Of Synthetic Cathinones Using Portable Mass Spectrometric Instrumentation, Caitlin N. Cain Jan 2016

Forensic Chemical Analysis Of Synthetic Cathinones Using Portable Mass Spectrometric Instrumentation, Caitlin N. Cain

Undergraduate Research Posters

Forensic laboratories face issues with large backlogs on evidence needing to be analyzed is due to two reasons: budgeting issues and the emergence of designer drugs. Currently, forensic laboratory directors cite that there are a shortage of scientists to deal with the yearly increase in caseloads. Additionally, designer drugs like synthetic cathinones, commonly known as “bath salts,” have increased the backlog due to the changing chemical compositions and misidentification as other compounds. Therefore, the use of a portable mass spectrometer for on-site forensic chemical analysis of synthetic cathinones would reduce the backlog of suspected controlled substances in forensic chemistry laboratories. …


Planetary Bioresources And Astroecology 1. Planetary Microcosm Bioassays Of Martian And Carbonaceous Chondrite Materials: Nutrients, Electrolyte Solutions, And Algal And Plant Responses, Michael Noah Mautner Jan 2002

Planetary Bioresources And Astroecology 1. Planetary Microcosm Bioassays Of Martian And Carbonaceous Chondrite Materials: Nutrients, Electrolyte Solutions, And Algal And Plant Responses, Michael Noah Mautner

Chemistry Publications

The biological fertilities of planetary materials can be assessed using microcosms based on materials in martian and carbonaceous chondrite meteorites. Their biological fertilities are rated based on soluble electrolyte nutrients, on the growth of mesophile and cold-tolerant algae, and of plant tissue cultures. The Murchison CM2 carbonaceous chondrite meteorite and DaG 476 martian shergottite contain high levels of water-extractable Ca, Mg, and SO4–S. The martian meteorites DaG 476 and EETA 79001 also contain high levels of extractable nutrients NO3–N (0.013–0.017 g kg1) and PO4–P (0.019–0.046 g kg1). The yields of most of the water-extractable …


Development Of Quasi-Likelihood Techniques For The Analysis Of Pseudo-Proportional Data, Jennifer A. Elder Jan 1996

Development Of Quasi-Likelihood Techniques For The Analysis Of Pseudo-Proportional Data, Jennifer A. Elder

Theses and Dissertations

In certain experimental situations, the data observed are pseudo-proportional. By this, we observe the numerator, the number of responders, but the denominator, the total number, is random and, possibly, unobserved. In such situations, the data often exhibit "extra" variability due to the randomness of the denominator. Analysis of these data should account for this overdispersion. Several authors have proposed parametric approaches to this problem. Finney [Biometrika (1949) 36, 239-256] proposed the use of a mixture of the binomial and Poisson distributions. Anscombe [Annals of Applied Biology (1949) 36, 203-205] discussed the use of a mixture of the binomial and negative …