ASU Electronic Theses and Dissertations
This collection includes most of the ASU Theses and Dissertations from 2011 to present. ASU Theses and Dissertations are available in downloadable PDF format; however, a small percentage of items are under embargo. Information about the dissertations/theses includes degree information, committee members, an abstract, supporting data or media.
In addition to the electronic theses found in the ASU Digital Repository, ASU Theses and Dissertations can be found in the ASU Library Catalog.
Dissertations and Theses granted by Arizona State University are archived and made available through a joint effort of the ASU Graduate College and the ASU Libraries. For more information or questions about this collection contact or visit the Digital Repository ETD Library Guide or contact the ASU Graduate College at gradformat@asu.edu.
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Description
Carbonaceous chondrites (CCs) present a unique opportunity for learning about the earliest organic chemistry that took place in our Solar System. The complex and diverse suite of meteoritic organic material is the result of multiple settings and physicochemical processes, including aqueous and thermal alteration. Though meteorites often inform origin-of-life discussions because they could have seeded early Earth with significant amounts of water and pre-biotic, organic material, their record of abiotic, aqueous, and organic geochemistry is of interest as well.
CC materials previously resided on asteroidal parent bodies, relic planetesimals of Solar System formation which never accreted enough material to develop long-lived, large-scale geological processes. These bodies were large enough, however, to experience some degree of heating due to the decay of radiogenic isotopes, and the meteorite record suggests the existence of 100-150 parent bodies which experienced varying degrees of thermal and aqueous alteration for the first several 10 Myr of Solar System history.
The first chapter of this dissertation reviews literature addressing aqueous alteration as an essential participant in parent body geochemistry, organic synthesis, or both (though papers which address both are rare). The second chapter is a published organic analysis of the soluble organic material of Bells, an unclassified type 2 chondrite. Analytical approaches to assess terrestrial contamination of meteorite samples are also reviewed in the first chapter to allow introduction in chapter 3 of kinetic modeling which rules out certain cases of contamination and constrains the timing of thermal and aqueous alteration. This is the first known application of isoleucine epimerization for either of these purposes. Chapter 4 is a kinetic study of D-allo-isoleucine epimerization to establish its behavior in systems with large, relative abundances of alloisoleucine to isoleucine. Previous epimerization studies for paleontological or geological purposes began with L-isoleucine, the only protein amino acid of the four isoleucine stereoisomers.
Kinetic model calculations using isoleucine stereoisomer abundances from 7 CR chondrites constrain the total duration of the amino acids' residence in the aqueous phase. The comparatively short timescales produced by the presented modeling elicit hypotheses for protection or transport of the amino acids within the CR parent body.
CC materials previously resided on asteroidal parent bodies, relic planetesimals of Solar System formation which never accreted enough material to develop long-lived, large-scale geological processes. These bodies were large enough, however, to experience some degree of heating due to the decay of radiogenic isotopes, and the meteorite record suggests the existence of 100-150 parent bodies which experienced varying degrees of thermal and aqueous alteration for the first several 10 Myr of Solar System history.
The first chapter of this dissertation reviews literature addressing aqueous alteration as an essential participant in parent body geochemistry, organic synthesis, or both (though papers which address both are rare). The second chapter is a published organic analysis of the soluble organic material of Bells, an unclassified type 2 chondrite. Analytical approaches to assess terrestrial contamination of meteorite samples are also reviewed in the first chapter to allow introduction in chapter 3 of kinetic modeling which rules out certain cases of contamination and constrains the timing of thermal and aqueous alteration. This is the first known application of isoleucine epimerization for either of these purposes. Chapter 4 is a kinetic study of D-allo-isoleucine epimerization to establish its behavior in systems with large, relative abundances of alloisoleucine to isoleucine. Previous epimerization studies for paleontological or geological purposes began with L-isoleucine, the only protein amino acid of the four isoleucine stereoisomers.
Kinetic model calculations using isoleucine stereoisomer abundances from 7 CR chondrites constrain the total duration of the amino acids' residence in the aqueous phase. The comparatively short timescales produced by the presented modeling elicit hypotheses for protection or transport of the amino acids within the CR parent body.
ContributorsMonroe, Adam Alexander (Author) / Pizzarello, Sandra (Thesis advisor) / Williams, Peter (Thesis advisor) / Anbar, Ariel D (Committee member) / Shock, Everett L (Committee member) / Arizona State University (Publisher)
Created2014
Description
A new challenge on the horizon is to utilize the large amounts of protein found in the atmosphere to identify different organisms from which the protein originated. Included here is work investigating the presence of identifiable patterns of different proteins collected from the air and biological samples for the purposes of remote identification. Protein patterns were generated using high performance liquid chromatography (HPLC). Patterns created could identify high-traffic and low-traffic indoor spaces. Samples were collected from the air using air pumps to draw air through a filter paper trapping particulates, including large amounts of shed protein matter. In complimentary research aerosolized biological samples were collected from various ecosystems throughout Ecuador to explore the relationship between environmental setting and aerosolized protein concentrations. In order to further enhance protein separation and produce more detailed patterns for the identification of individual organisms of interest; a novel separation device was constructed and characterized. The separation device incorporates a longitudinal gradient as well as insulating dielectrophoretic features within a single channel. This design allows for the production of stronger local field gradients along a global gradient allowing particles to enter, initially transported through the channel by electrophoresis and electroosmosis, and to be isolated according to their characteristic physical properties, including charge, polarizability, deformability, surface charge mobility, dielectric features, and local capacitance. Thus, different types of particles are simultaneously separated at different points along the channel distance given small variations of properties. The device has shown the ability to separate analytes over a large dynamic range of size, from 20 nm to 1 μm, roughly the size of proteins to the size of cells. In the study of different sized sulfate capped polystyrene particles were shown to be selectively captured as well as concentrating particles from 103 to 106 times. Qualitative capture and manipulation of β-amyloid fibrils were also shown. The results demonstrate the selective focusing ability of the technique; and it may form the foundation for a versatile tool for separating complex mixtures. Combined this work shows promise for future identification of individual organisms from aerosolized protein as well as for applications in biomedical research.
ContributorsStaton, Sarah J. R (Author) / Hayes, Mark A. (Committee member) / Anbar, Ariel D (Committee member) / Shock, Everett (Committee member) / Williams, Peter (Committee member) / Arizona State University (Publisher)
Created2011