Theses and Dissertations
This collection includes both ASU Theses and Dissertations, submitted by graduate students, and the Barrett, Honors College theses submitted by undergraduate students.
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- Creators: School of Mathematical and Natural Sciences
- Creators: Mokwa, Michael
Description
We apply a Bayesian network-based approach for determining the structure of consumers' brand concept maps, and we further extend this approach in order to provide a precise delineation of the set of cognitive variations of that brand concept map structure which can simultaneously coexist within the data. This methodology can operate with nonlinear as well as linear relationships between the variables, and utilizes simple Likert-style marketing survey data as input. In addition, the method can operate without any a priori hypothesized structures or relations among the brand associations in the model. The resulting brand concept map structures delineate directional (as opposed to simply correlational) relations among the brand associations, and differentiates between the predictive and the diagnostic directions within each link. Further, we determine a Bayesian network-based link strength measure, and apply it to a comparison of the strengths of the connections between different semantic categories of brand association descriptors, as well as between different strategically important drivers of brand differentiation. Finally, we apply a precise form of information propagation through the predictive and diagnostic links within the network in order to evaluate the effect of introducing new information to the brand concept network. This overall methodology operates via a factorization of the joint distribution of the brand association variables via conditional independence properties and an application of the causal Markov condition, and as such, it represents an alternative approach to correlation-based structural determination methods. By using conditional independence as a core structural construct, the methods utilized here are especially well- suited for determining and analyzing asymmetric or directional beliefs about brand or product attributes. This methodology builds on the pioneering Brand Concept Mapping approach of Roedder John et al. (2006). Similar to that approach, the Bayesian network-based method derives the specific link-by-link structure among a brand's associations, and also allows for a precise quantitative determination of the likely effects that manipulation of specific brand associations will have upon other strategically important associations within that brand image. In addition, the method's precise informational semantics and specific structural measures allow for a greater understanding of the structure of these brand associations.
ContributorsBrownstein, Steven Alan (Author) / Reingen, Peter (Thesis advisor) / Kumar, Ajith (Committee member) / Mokwa, Michael (Committee member) / Arizona State University (Publisher)
Created2013
Description
Convergent products are products that offer multiple capabilities from different product categories. For example, a smartphone acts as an internet browser, personal assistant, and telephone. Marketers are constantly considering the value of adding new functionalities to these convergent products. This work examines convergent products in terms of the hedonic and utilitarian value they provide along with whether the addition is related to the base product, revealing complex and nuanced interactions. This work contributes to marketing theory by advancing knowledge in the convergent products and product design literatures, specifically by showing how hedonic and utilitarian value and addition relatedness interact to impact the evaluation of convergent goods and services. Looking at a greater complexity of convergent product types also helps to resolve prior conflicting findings in the convergent products and hedonic and utilitarian value literatures. Additionally, this work examines the role of justification in convergent products, showing how different additions can help consumers to justify the evaluation of a convergent product. A three-item measure for justification was developed for this research, and can be used by future researchers to better understand the effects of justification in consumption. This work is also the first to explicitly compare effects between convergent goods and convergent services. Across two experiments, it is found that these two products types (convergent goods versus convergent services) are evaluated differently. For convergent goods, consumers evaluate additions based on anticipated practicality/productivity and on how easily they are justified. For convergent services, consumers evaluate additions based on perceptions of performance risk associated with the convergent service, which stems from the intangibility of these services. The insights gleaned from the research allow specific recommendations to be made to managers regarding convergent offerings. This research also examines the applicability of hedonic and utilitarian value to a special type of advertising appeal: reward appeals. Reward appeals are appeals that focus on peripheral benefits from purchasing or using a product, such as time or money savings, and make suggestions on how to use these savings. This work examines potential interactions between reward appeals and other common advertising elements: social norms information and role clarity messaging.
ContributorsEaton, Kathryn Karnos (Author) / Bitner, Mary Jo (Thesis advisor) / Olsen, G. Douglas (Thesis advisor) / Mokwa, Michael (Committee member) / Arizona State University (Publisher)
Created2012
Description
The focus of human decomposition studies has traditionally been on how external factors affect the decomposition of a body. There is much less literature on how the decomposition of a human cadaver affects its local ecosystem. This study attempts to address the knowledge gap in current literature regarding how the decomposition of human cadavers affects the bioavailability of essential plant nutrients (P, K, Ca, Fe, C and N) as well as toxins (As and Pb) in soil. By studying the bioavailability of plant nutrients, especially nitrogen, and toxins, this research hopes to inform new technologies and techniques for locating clandestine gravesites. The objectives of this study were twofold: 1) determine whether soils exposed to cadaveric decomposition can be visually distinguished from one another via macroscopic and microscopic observation and 2) observe general changes in nutrient and toxic element bioavailability and changes in carbon and nitrogen isotope ratios over time as well as spatially across a body. Visual analyses of soil samples, both macro- and microscopically did not show potential in distinguishing soil exposed to cadaver decomposition from unexposed soil. Relative bioavailability as well as overall bioavailable concentrations of both plant nutrients and toxins were highly elevated after 12 months. Toxins, such as As and Pb, tended to have greater bioavailable concentrations at the near-torso positions, though no consistent spatial trends between nutrient bioavailable concentrations were observed between the three individuals. Nitrogen concentrations and nitrogen isotope (δ15N) ratios show strong potential as markers of clandestine graves throughout the study period. While this research demonstrates further need to uncover what factors influence bioavailability of elements in gravesoil, it shows that the bioavailability of plant nutrients and toxins as well as δ15N ratios are greatly affected by cadaver decomposition, and emerging technologies in gravesite detection based on plant or soil changes have a solid foundation.
ContributorsAnderson, Sara Rae (Author) / Kobojek, Kimberly (Thesis director) / Gordon, Gwyneth (Committee member) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Criminal Justice is a complex subject matter, and not everyone agrees on the way a criminal justice system ought to function. But one feature that is common to virtually all forms of proposed justice systems is that a true justice system treats people ethically. The question, then, is how a justice system can achieve this. This investigation analyzed two ethical theories, Kantianism and Utilitarianism, to determine which one would be better suited for guiding a criminal justice system on how to treat the people involved ethically. This investigation focused on applying the two theories to the U.S. Criminal Justice System in particular.
Kantianism is a duty-based moral theory in which actions have an intrinsic moral worth. This means certain actions are morally right and other are morally wrong, regardless of the intended or realized consequences. The theory relies on the categorical imperative to judge the morality of certain actions. It states that an action is moral if its maxim can be willed universal law and if it avoids treating people as merely a means. In contrast, Utilitarianism is a consequentialist theory which focuses on the consequences of an action in judging moral worth. In Utilitarianism, the morally correct action is the one which will maximize utility; that is to say, the morally right action is the one which will produce the greatest amount of happiness and minimize the amount of pain for the greatest number of people.
After applying these two theories to moral dilemmas facing the U.S. Criminal Justice System, including the appropriate collection of DNA evidence, the use of police deception, and the use of criminal punishments such as solitary confinement or the death penalty, it was clear that Kantianism was the ethical theory best suited for guiding the system in treating people ethically. This is because Kantianism’s focus on the intrinsic moral worth of an action rather than its consequences leaves less room for ambiguity than does Utilitarianism.
Kantianism is a duty-based moral theory in which actions have an intrinsic moral worth. This means certain actions are morally right and other are morally wrong, regardless of the intended or realized consequences. The theory relies on the categorical imperative to judge the morality of certain actions. It states that an action is moral if its maxim can be willed universal law and if it avoids treating people as merely a means. In contrast, Utilitarianism is a consequentialist theory which focuses on the consequences of an action in judging moral worth. In Utilitarianism, the morally correct action is the one which will maximize utility; that is to say, the morally right action is the one which will produce the greatest amount of happiness and minimize the amount of pain for the greatest number of people.
After applying these two theories to moral dilemmas facing the U.S. Criminal Justice System, including the appropriate collection of DNA evidence, the use of police deception, and the use of criminal punishments such as solitary confinement or the death penalty, it was clear that Kantianism was the ethical theory best suited for guiding the system in treating people ethically. This is because Kantianism’s focus on the intrinsic moral worth of an action rather than its consequences leaves less room for ambiguity than does Utilitarianism.
ContributorsMorett, Xavier Laakea (Author) / Manninen, Bertha (Thesis director) / Kimberly, Kobojek (Committee member) / School of Criminology and Criminal Justice (Contributor) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Calcium is the only ion capable of triggering electrical and chemical reactions in cells which are part of essential biomolecular processes, such as gene transcription and ion flux. Calcium homeostasis, the control of concentration levels, is therefore crucial for the proper functioning of cells. For example, cardiomyocytes, the cells that form cardiac muscle, rely on calcium transfer process to produce muscle contraction.
The purpose of this work is to study aspects of calcium homeostasis in the model organism Saccharomyces cerevisiae, common yeast. Using luminometric techniques, the response of the yeast was monitored against a set of changes in the environment calcium abundance. The results indicate a complex response as both increase and decreases of external calcium induce elevations in cytosolic calcium concentrations.
Calcium is transferred across compartments by means of channels. In Saccharomyces cerevisiae, many of them have been identified; Cch1p-Mid1p, Vcx1p, Pmc1p, Pmr1p, and Yvc1p. Their participation in calcium homeostasis is well established. Observations of cytosolic calcium increase after a hypertonic shock are mainly associated with influx of ions from the environment though the Cch1p-Mid1p. This process is generally considered as driven by calcium concentration gradients. However, recent studies have suggested that the plasma membrane channel, Cch1p-Mid1p, may possess more sophisticated regulation and sensory mechanisms. The results of our experiments support these ideas.
We carried out experiments that subjected yeast to multiple shocks: a hypertonic shock followed by either a second hypertonic shock, a hypotonic shock, or a yeast dilution pulse where the solution volume increases by the calcium concentration has only a small change. The cytosolic calcium concentration of a yeast population was monitored via luminometry.
The main result of this study is the observation of an unexpected response to the combination of hypertonic and hypotonic shocks. In this case it was observed that the cytosolic calcium concentration increased after both shocks. This indicates that cytosolic calcium increases are not solely driven by the presence of concentration gradients. The response after the hypotonic pulse arises from more complex mechanisms that may include sensor activity at the membrane channels and the release of calcium from internal storages.
The purpose of this work is to study aspects of calcium homeostasis in the model organism Saccharomyces cerevisiae, common yeast. Using luminometric techniques, the response of the yeast was monitored against a set of changes in the environment calcium abundance. The results indicate a complex response as both increase and decreases of external calcium induce elevations in cytosolic calcium concentrations.
Calcium is transferred across compartments by means of channels. In Saccharomyces cerevisiae, many of them have been identified; Cch1p-Mid1p, Vcx1p, Pmc1p, Pmr1p, and Yvc1p. Their participation in calcium homeostasis is well established. Observations of cytosolic calcium increase after a hypertonic shock are mainly associated with influx of ions from the environment though the Cch1p-Mid1p. This process is generally considered as driven by calcium concentration gradients. However, recent studies have suggested that the plasma membrane channel, Cch1p-Mid1p, may possess more sophisticated regulation and sensory mechanisms. The results of our experiments support these ideas.
We carried out experiments that subjected yeast to multiple shocks: a hypertonic shock followed by either a second hypertonic shock, a hypotonic shock, or a yeast dilution pulse where the solution volume increases by the calcium concentration has only a small change. The cytosolic calcium concentration of a yeast population was monitored via luminometry.
The main result of this study is the observation of an unexpected response to the combination of hypertonic and hypotonic shocks. In this case it was observed that the cytosolic calcium concentration increased after both shocks. This indicates that cytosolic calcium increases are not solely driven by the presence of concentration gradients. The response after the hypotonic pulse arises from more complex mechanisms that may include sensor activity at the membrane channels and the release of calcium from internal storages.
ContributorsMintz, David Anthony (Co-author) / Parker, Augustus (Co-author) / Solis, Francisco (Thesis director) / Marshall, Pamela (Committee member) / School of Mathematical and Natural Sciences (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Calcium is the only ion capable of triggering electrical and chemical reactions in cells which are part of essential biomolecular processes, such as gene transcription and ion flux. Calcium homeostasis, the control of concentration levels, is therefore crucial for the proper functioning of cells. For example, cardiomyocytes, the cells that form cardiac muscle, rely on calcium transfer process to produce muscle contraction.
The purpose of this work is to study aspects of calcium homeostasis in the model organism Saccharomyces cerevisiae, common yeast. Using luminometric techniques, the response of the yeast was monitored against a set of changes in the environment calcium abundance. The results indicate a complex response as both increase and decreases of external calcium induce elevations in cytosolic calcium concentrations.
Calcium is transferred across compartments by means of channels. In Saccharomyces cerevisiae, many of them have been identified; Cch1p-Mid1p, Vcx1p, Pmc1p, Pmr1p, and Yvc1p. Their participation in calcium homeostasis is well established. Observations of cytosolic calcium increase after a hypertonic shock are mainly associated with influx of ions from the environment though the Cch1p-Mid1p. This process is generally considered as driven by calcium concentration gradients. However, recent studies have suggested that the plasma membrane channel, Cch1p-Mid1p, may possess more sophisticated regulation and sensory mechanisms. The results of our experiments support these ideas.
We carried out experiments that subjected yeast to multiple shocks: a hypertonic shock followed by either a second hypertonic shock, a hypotonic shock, or a yeast dilution pulse where the solution volume increases by the calcium concentration has only a small change. The cytosolic calcium concentration of a yeast population was monitored via luminometry.
The main result of this study is the observation of an unexpected response to the combination of hypertonic and hypotonic shocks. In this case it was observed that the cytosolic calcium concentration increased after both shocks. This indicates that cytosolic calcium increases are not solely driven by the presence of concentration gradients. The response after the hypotonic pulse arises from more complex mechanisms that may include sensor activity at the membrane channels and the release of calcium from internal storages.
The purpose of this work is to study aspects of calcium homeostasis in the model organism Saccharomyces cerevisiae, common yeast. Using luminometric techniques, the response of the yeast was monitored against a set of changes in the environment calcium abundance. The results indicate a complex response as both increase and decreases of external calcium induce elevations in cytosolic calcium concentrations.
Calcium is transferred across compartments by means of channels. In Saccharomyces cerevisiae, many of them have been identified; Cch1p-Mid1p, Vcx1p, Pmc1p, Pmr1p, and Yvc1p. Their participation in calcium homeostasis is well established. Observations of cytosolic calcium increase after a hypertonic shock are mainly associated with influx of ions from the environment though the Cch1p-Mid1p. This process is generally considered as driven by calcium concentration gradients. However, recent studies have suggested that the plasma membrane channel, Cch1p-Mid1p, may possess more sophisticated regulation and sensory mechanisms. The results of our experiments support these ideas.
We carried out experiments that subjected yeast to multiple shocks: a hypertonic shock followed by either a second hypertonic shock, a hypotonic shock, or a yeast dilution pulse where the solution volume increases by the calcium concentration has only a small change. The cytosolic calcium concentration of a yeast population was monitored via luminometry.
The main result of this study is the observation of an unexpected response to the combination of hypertonic and hypotonic shocks. In this case it was observed that the cytosolic calcium concentration increased after both shocks. This indicates that cytosolic calcium increases are not solely driven by the presence of concentration gradients. The response after the hypotonic pulse arises from more complex mechanisms that may include sensor activity at the membrane channels and the release of calcium from internal storages.
ContributorsParker, Augustus Carrucciu (Co-author) / Mintz, David (Co-author) / Solis, Francisco (Thesis director) / Marshall, Pamela (Committee member) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Cellular and molecular biologists often perform cellular assays to obtain a better understanding of how cells work. However, in order to obtain a measurable response by the end of an experiment, the cells must reach an ideal cell confluency. Prior to conducting the cellular assays, range-finding experiments need to be conducted to determine an initial plating density that will result in this ideal confluency, which can be costly. To help alleviate this common issue, a mathematical model was developed that describes the dynamics of the cell population used in these experiments. To develop the model, images of cells from different three-day experiments were analyzed in Photoshop®, giving a measure of cell count and confluency (the percentage of surface area covered by cells). The cell count data were then fitted into an exponential growth model and were correlated to the cell confluency to obtain a relationship between the two. The resulting mathematical model was then evaluated with data from an independent experiment. Overall, the exponential growth model provided a reasonable and robust prediction of the cell confluency, though improvements to the model can be made with a larger dataset. The approach used to develop this model can be adapted to generate similar models of different cell-lines, which will reduce the number of preliminary range-finding experiments. Reducing the number of these preliminary experiments can save valuable time and experimental resources needed to conduct studies using cellular assays.
ContributorsGuerrero, Victor Dominick (Co-author) / Guerrero, Victor (Co-author) / Watanabe, Karen (Thesis director) / Jurutka, Peter (Committee member) / School of Mathematical and Natural Sciences (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
A lab protocol was created in order to introduce arson evidence analysis to students. The procedures dictate a thorough introduction from evidence handling procedures to analysis of common accelerant mass spectrum. The objectives of the lab protocol included classifying and describing various pieces of arson evidence and common accelerants as well as synthesizing information about accelerant composition to interpret GC-MS data output. This would allow the student to experience first-hand what the subsection of arson analysis has to offer in the field of forensic science which could help the student decide on more specialties to study later on. I was unable to run the lab protocol in a laboratory setting, therefore in the future I want to use the lab protocol and receive feedback in order to improve the protocol so the student is receiving the best possible learning outcomes. The experience of creating a lab protocol in forensic science gave myself a greater understanding of what goes on behind an academic learning procedure and more insight on arson evidence analysis.
ContributorsWhitten, Jamison Mckall (Author) / Kobojek, Kimberly (Thesis director) / Armendariz Guajardo, Jose (Committee member) / School of Criminology and Criminal Justice (Contributor) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Capsaicin and dihydrocapsaicin account for 90% of capsaicinoids when it comes to the pungency of peppers. Capsaicin stability was investigated through a cooking and storage parameter where three different tests were done; cooking duration, cooking temperature, and storage stability. The concentration of capsaicinoids was quantified through gas chromatography-mass spectrometry where those values were then used to determine the total Scoville heat units (SHU). Furthermore, half-life was determined by finding the decay rate during cooking and storage. Results showed that there was an increase in degradation of capsaicinoids concentration when peppers were cooked for a long period of time. Degradation rate increases with increasing temperatures as would be expected by the Arrhenius equation. Hence, if a maximum pungency is wanted, it is best to cook the least time as possible or add the peppers towards the end of the culinary technique. This would help by cooking the peppers for a short period of time while not being exposed to the high temperature long enough before significant degradation occurs. Lastly, the storage stability results interpreted that a maximum potency of the peppers can be retained in a freezer or refrigerator opposed to an open room temperature environment or exposure from the sun. Furthermore, the stability of peppers has a long shelf life with even that the worse storage condition's half-life value was 113.5 months (9.5 years). Thus, peppers do not need to be bought frequently because its potency will last for several years.
ContributorsBustamante, Krista Gisselle (Author) / Cahill, Thomas (Thesis director) / Sweat, Ken (Committee member) / Armendariz Guajardo, Jose (Committee member) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
Description
Vitamin D, Klotho, and FOXO3 have all been linked to have anti-aging and anti-cancerous effects as separate pathways. Specifically, mice with knockout Klotho in their genes have displayed signs of premature aging, humans who are vitamin D deficient have been shown to develop cardiovascular disease and cognitive impairments, and those who have displayed overexpression of FOXO3 have shown to have a longer lifespan. Here we took each pathway and attempted to formulate a feedback mechanism loop linking all three separate pathways. We propose that vitamin D levels modulate klotho activity, including the expression of the s-klotho and m-klotho isoforms. Moreover, the anti-oxidation transcription factor FOXO3 is also thought to participate in crosstalk with VDR signaling. Through the connection between 1,25D and Klotho, we probed at their interactions with FOXO3 signaling in kidney and colon cells, and proposed that vitamin D and klotho may reduce oxidative stress and suppress the onset of epithelial cancers through it effects on FOXO3. Results showed a strong support for the cooperation between FOXO3 and 1,25D to stimulate both superoxide dismutase (a FOXO3 response element) and XDR3/ROC (vitamin D response elements). This cooperation was mostly seen in embryonic kidney cells (HEK293) and not in the colon cancer cells (HCT116), which has led to the conclusion that vitamin D and FOXO3 cooperation mainly occurs in kidney tissue and/or in tissue that is not yet been overtaken by cancer. Differences in the Klotho isoforms were seen when measuring FOXO3 and vitamin D activity, but experiments manipulating other components will need to be conducted to further understand the function of Klotho in maintaining reactive oxygenated species levels.
ContributorsSandoval, Ruby (Author) / Jurutka, Peter (Thesis director) / Sandrin, Todd R. (Committee member) / Heck, Michael (Committee member) / School of Social and Behavioral Sciences (Contributor) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05