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The earliest Eocene marked the appearance of the first North American euprimates (adapids, omomyids). Despite the fact that leading hypotheses assert that traits involved in food acquisition underlie euprimate origination and early diversification, the precise role that dietary competition played in establishing euprimates as successful members of mammalian communities is

The earliest Eocene marked the appearance of the first North American euprimates (adapids, omomyids). Despite the fact that leading hypotheses assert that traits involved in food acquisition underlie euprimate origination and early diversification, the precise role that dietary competition played in establishing euprimates as successful members of mammalian communities is unclear. This is because the degree of niche overlap between euprimates and all likely mammalian dietary competitors ("the euprimate competitive guild") is unknown. This research determined which of three major competition hypotheses - non-competition, strong competition, and weak competition - characterized the late Paleocene-early Eocene euprimate competitive guild. Each of these hypotheses is defined by a unique temporal pattern of niche overlap between euprimates and their non-euprimate competitors, allowing an evaluation of the nature of dietary competitive interactions surrounding the earliest euprimates in North America. Dietary niches were reconstructed for taxa within the fossil euprimate competitive guild using molar morphological measures determined to discriminate dietary regimes in two extant mammalian guilds. The degree of dietary niche separation among taxa was then evaluated across a series of fossil samples from the Bighorn Basin, Wyoming just prior to, during, and after euprimate origination. Statistical overlap between each pair of euprimate and non-euprimate dietary niches was determined using modified multivariate pairwise comparisons using distances in a multidimensional principal component "niche" space. Results indicate that euprimate origination and diversification in North America was generally characterized by the absence of dietary competition. This lack of competition with non-euprimates is consistent with an increase in the abundance and diversity of euprimates during the early Eocene, signifying that the "success" of euprimates may not be the result of direct biotic interactions between euprimates and other mammals. An examination of the euprimate dietary niche itself determined that adapids and omomyids occupied distinct niches and did not engage in dietary competition during the early Eocene. Furthermore, changes in euprimate dietary niche size over time parallel major climatic shifts. Reconstructing how both biotic and abiotic mechanisms affected Eocene euprimates has the potential to enhance our understanding of these influences on modern primate communities.
ContributorsStroik, Laura (Author) / Schwart, Gary T (Thesis advisor) / Reed, Kaye E (Committee member) / Campisano, Christopher J (Committee member) / Gunnell, Gregg F. (Committee member) / Arizona State University (Publisher)
Created2014
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Description
In a 2004 paper, John Nagy raised the possibility of the existence of a hypertumor \emph{i.e.}, a focus of aggressively reproducing parenchyma cells that invade part or all of a tumor. His model used a system of nonlinear ordinary differential equations to find a suitable set of conditions for which

In a 2004 paper, John Nagy raised the possibility of the existence of a hypertumor \emph{i.e.}, a focus of aggressively reproducing parenchyma cells that invade part or all of a tumor. His model used a system of nonlinear ordinary differential equations to find a suitable set of conditions for which these hypertumors exist. Here that model is expanded by transforming it into a system of nonlinear partial differential equations with diffusion, advection, and a free boundary condition to represent a radially symmetric tumor growth. Two strains of parenchymal cells are incorporated; one forming almost the entirety of the tumor while the much more aggressive strain

appears in a smaller region inside of the tumor. Simulations show that if the aggressive strain focuses its efforts on proliferating and does not contribute to angiogenesis signaling when in a hypoxic state, a hypertumor will form. More importantly, this resultant aggressive tumor is paradoxically prone to extinction and hypothesize is the cause of necrosis in many vascularized tumors.
ContributorsAlvarez, Roberto L (Author) / Milner, Fabio A (Thesis advisor) / Nagy, John D. (Committee member) / Kuang, Yang (Committee member) / Thieme, Horst (Committee member) / Mahalov, Alex (Committee member) / Smith, Hal (Committee member) / Arizona State University (Publisher)
Created2014
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Description
The viscous lung mucus of cystic fibrosis (CF) patients is characterized by oxygen gradients, which creates a unique niche for bacterial growth. Pseudomonas aeruginosa and Staphylococcus aureus, two predominant microorganisms chronically infecting the airways of CF patients, typically localize in hypoxic regions of the mucus. While interspecies interactions between P.

The viscous lung mucus of cystic fibrosis (CF) patients is characterized by oxygen gradients, which creates a unique niche for bacterial growth. Pseudomonas aeruginosa and Staphylococcus aureus, two predominant microorganisms chronically infecting the airways of CF patients, typically localize in hypoxic regions of the mucus. While interspecies interactions between P. aeruginosa and S. aureus have been reported, little is known about the role of low oxygen in regulating these interactions. Studying interspecies interactions in CF lung disease is important as evidence suggests that microbial community composition governs disease progression. In this study, P. aeruginosa lab strain PAO1 and two primary clinical isolates from hypoxic tissues were cultured alone, or in combination, with methicillin resistant S. aureus (MRSA) strain N315 under hypoxic or normoxic conditions. Herein, it is shown for the first time that low oxygen conditions relevant to the CF lung affect the competitive behavior between P. aeruginosa and S. aureus. Specifically, S. aureus was able to better survive competition in hypoxic versus normoxic conditions. Competition data from different oxygen concentrations were consistent using PAO1 and clinical isolates even though differences in the level of competition were observed. PAO1 strains carrying mutations in virulence factors known to contribute to S. aureus competition (pyocyanin/phzS, elastase/lasA and lasI quorum sensing/lasI) were used to determine which genes play a role in the differential growth inhibition. The lasA and lasI mutants competed less effectively with S. aureus regardless of the oxygen level present in the culture compared to the isogenic wild type strain. These results are consistent with previous findings that elastase and lasI quorum sensing play a role in competitive behavior of P. aeruginosa and S. aureus. Interestingly, the phzS mutant competed less effectively in hypoxic conditions suggesting that pyocyanin may be important in microaerophilic conditions. This study demonstrates that oxygen plays a role in competition between P. aeruginosa and S. aureus and contributes to understanding CF environmental factors that may regulate microbial community dynamics important for disease progression with potential for development of therapeutic avenues.
ContributorsLedesma Barrera, Maria Alexandra (Author) / Nickerson, Cheryl A. (Thesis advisor) / Reyes del Valle, Jorge (Committee member) / Clark-Curtiss, Josephine (Committee member) / Stout, Valerie (Committee member) / Ott, C M (Committee member) / Arizona State University (Publisher)
Created2014
Description
Highly active in the fields of viola performance, composition, recording, and pedagogy, Lionel Tertis is known as one of the first and most influential career violists. Established in 1980, the Lionel Tertis International Viola Competition and Festival was founded in his honor and occurs triennially at the Isle of Man.

Highly active in the fields of viola performance, composition, recording, and pedagogy, Lionel Tertis is known as one of the first and most influential career violists. Established in 1980, the Lionel Tertis International Viola Competition and Festival was founded in his honor and occurs triennially at the Isle of Man. While addressing facets of the professional violist with workshops, lectures, and masterclasses, this event provides a venue for competitive performers, acting as a platform for new viola repertoire.

Each competitor must prepare an extensive set of viola repertoire, among which is a compulsory piece for unaccompanied viola by an English composer. These commissioned works require the virtuosity and expression available within a contemporary musical language; this additionally challenges competitors to provide an artistic interpretation relatively untouched by tradition or common practice.

Although these pieces are written specifically for the competition, the commissioned works have the capacity to reach beyond the competition sphere and are highly programmable in most recital and solo performance settings. These pieces provide the contemporary violist with a greater selection of repertoire that displays idiomatic and expressive strengths of the viola.

My project commemorates the contributions of Lionel Tertis to the advancement of viola repertoire and performance with the study of works written a century post his prolific career. The secondary intent is to provide biographical information about each composer and to explore how these highly programmable works enrich the violist and their repertoire, ultimately bringing recognition to these new works for solo viola. Through biographical research, musical analysis, interviews and the recording process, I will provide a performer's analysis and supplemental recordings for three of these works: Darkness Draws In by David Matthews, Sonatine I by Roger Steptoe and Through a Limbeck by John Woolrich.
ContributorsWuenschel, Allyson Kay (Author) / Buck, Nancy (Thesis advisor) / Carpenter, Ellon (Committee member) / Ryan, Russell (Committee member) / Arizona State University (Publisher)
Created2017
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Description
Science is a formalized method for acquiring information about the world. In

recent years, the ability of science to do so has been scrutinized. Attempts to reproduce

findings in diverse fields demonstrate that many results are unreliable and do not

generalize across contexts. In response to these concerns, many proposals for reform have

emerged.

Science is a formalized method for acquiring information about the world. In

recent years, the ability of science to do so has been scrutinized. Attempts to reproduce

findings in diverse fields demonstrate that many results are unreliable and do not

generalize across contexts. In response to these concerns, many proposals for reform have

emerged. Although promising, such reforms have not addressed all aspects of scientific

practice. In the social sciences, two such aspects are the diversity of study participants

and incentive structures. Most efforts to improve scientific practice focus on replicability,

but sidestep issues of generalizability. And while researchers have speculated about the

effects of incentive structures, there is little systematic study of these hypotheses. This

dissertation takes one step towards filling these gaps. Chapter 1 presents a cross-cultural

study of social discounting – the purportedly fundamental human tendency to sacrifice

more for socially-close individuals – conducted among three diverse populations (U.S.,

rural Indonesia, rural Bangladesh). This study finds no independent effect of social

distance on generosity among Indonesian and Bangladeshi participants, providing

evidence against the hypothesis that social discounting is universal. It also illustrates the

importance of studying diverse human populations for developing generalizable theories

of human nature. Chapter 2 presents a laboratory experiment with undergraduates to test

the effect of incentive structures on research accuracy, in an instantiation of the scientific

process where the key decision is how much data to collect before submitting one’s

findings. The results demonstrate that rewarding novel findings causes respondents to

make guesses with less information, thereby reducing their accuracy. Chapter 3 presents

an evolutionary agent-based model that tests the effect of competition for novel findings

on the sample size of studies that researchers conduct. This model demonstrates that

competition for novelty causes the cultural evolution of research with smaller sample

sizes and lower statistical power. However, increasing the startup costs to conducting

single studies can reduce the negative effects of competition, as can rewarding

publication of secondary findings. These combined chapters provide evidence that

aspects of current scientific practice may be detrimental to the reliability and

generalizability of research and point to potential solutions.
ContributorsTiokhin, Leonid (Author) / Hruschka, Daniel J (Thesis advisor) / Morgan, Thomas JH (Thesis advisor) / Boyd, Robert (Committee member) / Frankenhuis, Willem E. (Committee member) / Bergstrom, Carl T. (Committee member) / Arizona State University (Publisher)
Created2018
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Description
In competitive Taekwondo, Electronic Body Protectors (EBPs) are used to register hits made by players during sparring. EBPs are comprised of three main components: chest guard, foot sock, and headgear. This equipment interacts with each other through the use of magnets, electric sensors, transmitters, and a receiver. The receiver is

In competitive Taekwondo, Electronic Body Protectors (EBPs) are used to register hits made by players during sparring. EBPs are comprised of three main components: chest guard, foot sock, and headgear. This equipment interacts with each other through the use of magnets, electric sensors, transmitters, and a receiver. The receiver is connected to a computer programmed with software to process signals from the transmitter and determine whether or not a competitor scored a point. The current design of EBPs, however, have numerous shortcomings, including sensing false positives, failing to register hits, costing too much, and relying on human judgment. This thesis will thoroughly delineate the operation of the current EBPs used and discuss research performed in order to eliminate these weaknesses.
ContributorsSpell, Valerie Anne (Author) / Kozicki, Michael (Thesis director) / Kitchen, Jennifer (Committee member) / Electrical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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Description
The traditional action-response perspective has largely ignored the role of language in competitive dynamics. In this study, I treat language (i.e., word response) as an alternative way to react to rivals when a firm is attacked, in addition to no reaction and action-based reaction. Word response is a specific and

The traditional action-response perspective has largely ignored the role of language in competitive dynamics. In this study, I treat language (i.e., word response) as an alternative way to react to rivals when a firm is attacked, in addition to no reaction and action-based reaction. Word response is a specific and public announcement of a focal firm’s potential move in reaction to a competitor’s word or action attack. To explore the underlying mechanism behind word responses, I aim to answer two major questions. The first question is under what situations are responders motivated to use words as competitive responses? For this question I emphasize characteristics of the action, the market, and the actor, using measures such as action type, market dependence of the responder, multimarket contact of the responder in the market, and the competitive aggressiveness of the actor. The second question is what kinds of responders are more likely to use words as competitive responses? For this question, I focus on responder characteristics, such as firm reputation, CEO tenure, and CEO duality. According to Porter’s competitive signaling theory, I argue that responders can use words in reaction to an attack in order to test the waters, deter rivalry, and demonstrate toughness because word responses require few resources, can be accomplished quickly, are reversible, while at the same time still carrying some commitment. Besides incorporating language into the action-response perspective, my dissertation also further integrates the upper-echelons perspective with competitive dynamics research, providing a more realistic and complete understanding of competitive engagement. I test my theory in the consumer electronics (CE) industry with 20 major global CE manufacturers between 2007 and 2014.
ContributorsGao, He (Author) / Cannella, Albert A. (Thesis advisor) / Yu, Tieying (Committee member) / Mesquita, Luiz (Committee member) / Arizona State University (Publisher)
Created2016
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Description
This study investigates the lived experience of competition in high school band and the manner in which competition influences and frames band curricula. A hermeneutic phenomenological method based on the works of van Manen and Vagle was used to investigate what it was like for participants to be in competition.

This study investigates the lived experience of competition in high school band and the manner in which competition influences and frames band curricula. A hermeneutic phenomenological method based on the works of van Manen and Vagle was used to investigate what it was like for participants to be in competition. A theoretical framework organized around Schwab's commonplaces of education was used to interpret findings related to the curricular areas of the teacher, learner, subject matter, and milieu. I examined data through a lens incorporating principles of John Dewey's philosophy related to each of the commonplaces.

Twelve individuals participated in the study representing experiences had both as students and as music educators. Participants lived and taught in communities throughout the United States and brought differing levels of teaching and competitive experience. Data were generated through in-depth interviews and collaborative phenomenological texts. Research questions included: What is the lived experience of competing in a high school band like?; and, How does competition frame and influence high school band curricula?

Findings indicate that competition was a meaningful and influential part of participants' work as band directors and educational experiences as students. Competition was approached with tension as participants acknowledged negative concerns over the influence of competitions on their students, yet chose to engage in competitive activities. Marching band contests offered a creative outlet where directors could develop custom materials and they did so with a significant motivation to win. Competition was perceived as an influence on band directors' professional reputations, feelings of competence, and how band programs were viewed in the community. Students were motivated by competitions and reacted strongly to competitive results such as rankings, ratings, and other distinctions.

Findings also indicate that band curricula emphasizing competition share similar curricular facets: (a) teachers carefully control and manage classroom activities and curricular choices; (b) students are viewed as skilled performers who are dependent upon their teachers for learning; (c) subject matter is narrowly considered around measurable behavioral objectives and repertoire selection; and, (d) the educational environment is dominated by the teacher who may use competition to motivate students to work and practice more.
ContributorsO'Leary, Emmett James (Author) / Tobias, Evan S (Thesis advisor) / Stauffer, Sandra L (Committee member) / Schmidt, Margaret (Committee member) / Sullivan, Jill M (Committee member) / Landes, Heather (Committee member) / Arizona State University (Publisher)
Created2016
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Description
Many animals thermoregulate to maximize performance. However, interactions with other animals, such as competitors or predators, limit access to preferred microclimates. For instance, an animal may thermoregulate poorly when fighting rivals or avoiding predators. However, the distribution of thermal resources should influence how animals perceive and respond to risk. When

Many animals thermoregulate to maximize performance. However, interactions with other animals, such as competitors or predators, limit access to preferred microclimates. For instance, an animal may thermoregulate poorly when fighting rivals or avoiding predators. However, the distribution of thermal resources should influence how animals perceive and respond to risk. When thermal resources are concentrated in space, individuals compete for access, which presumably reduces the thermoregulatory performance while making their location more predictable to predators. Conversely, when thermal resources are dispersed, several individuals can thermoregulate effectively without occupying the same area. Nevertheless, interactions with competitors or predators impose a potent stress, often resulting in both behavioral and physiological changes that influence thermoregulation. To assess the costs of intraspecific competition and predation risk during thermoregulation, I measured thermoregulation, movement, and hormones of male lizards (Sceloporus jarrovi) in experiment landscapes, with clumped to patchy distributions of microclimates. I found lizards aggressively competed for access to microclimates, with larger males gaining priority access when thermal resources were aggregated. Competition reduced thermoregulatory performance, increased movements, and elevated plasma corticosterone in large and small males. However, the magnitude of these responses decreased as the patchiness of the thermal environment increased. Similarly, under simulated predation risk, lizards reduced thermoregulatory performance, decreased movements, and elevated plasma corticosterone. Again, with the magnitude of these responses decreased with increasing thermal patchiness. Interestingly, even without competitors or predators, lizards in clumped arenas moved greater distances and circulated more corticosterone than did lizards in patchy arenas, indicating the thermal quality of the thermal landscape affected the energetic demands on lizards. Thus, biologists should consider species interactions and spatial structure when modeling impacts of climate change on thermoregulation.
ContributorsRusch, Travis W (Author) / Angilletta, Michael (Thesis advisor) / Sears, Mike (Committee member) / DeNardo, Dale (Committee member) / Deviche, Pierre (Committee member) / McGraw, Kevin (Committee member) / Arizona State University (Publisher)
Created2017
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Description
School choice reforms such as charter schools, vouchers, open enrollment, and private and public school tax credit donation programs have expanded throughout the United States over the past twenty years. Arizona’s long-standing public school choice system enrolls a higher percentage of public school students in charter schools than any

School choice reforms such as charter schools, vouchers, open enrollment, and private and public school tax credit donation programs have expanded throughout the United States over the past twenty years. Arizona’s long-standing public school choice system enrolls a higher percentage of public school students in charter schools than any state besides Washington D.C. A growing number of Arizona’s charter schools are managed by for-profit and nonprofit Education Management Organizations (EMOs). Advocates of school choice argue that free-market education approaches will make public schools competitive and nimble as parents’ choices place pressures on schools to improve or close. This, then, improves all schools: public, private, and charter. Critics are concerned that education markets produce segregation along racial and social class lines and inequalities in educational opportunities, because competition favors advantaged parents and children who can access resources. Private and for-profit schools may see it in their interest to exclude students who require more support. School choice programs, then, may further marginalize students who live in poverty, who receive special education services, and English language learners.

We do not fully understand how Arizona’s mature school choice system affects parents and other stakeholders in communities “on the ground.” That is, how are school policies understood and acted out? I used ethnographic methods to document and analyze the social, cultural, and political contexts and perspectives of stakeholders at one district public school and in its surrounding community, including its charter schools. I examined: (a) how stakeholders perceived and engaged with schools; (b) how stakeholders understood school policies, including school choice policies; and (c) what influenced families’ choices.

Findings highlight how most stakeholders supported district public schools. At the same time, some “walked the line” between choices that were good for their individual families and those they believed were good for public schools and society. Stakeholders imagined “community” and “accountability” in a range of ways, and they did not all have equal access to policy knowledge. Pressures related to parental accountability in the education market were apparent as stakeholders struggled to make, and sometimes revisit, their choices, creating a tenuous schooling environment for their families.
ContributorsPotterton, Amanda U (Author) / Powers, Jeanne M. (Thesis advisor) / Berliner, David C. (Committee member) / Fischman, Gustavo E. (Committee member) / Glass, Gene V (Committee member) / Arizona State University (Publisher)
Created2017