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- Language: English
- Member of: ASU Electronic Theses and Dissertations
- Status: Published
Description
Food system and health characteristics were evaluated across the last Waorani hunter-gatherer group in Amazonian Ecuador and a remote neighboring Kichwa indigenous subsistence agriculture community. Hunter-gatherer food systems like the Waorani foragers may not only be nutritionally, but also pharmaceutically beneficial because of high dietary intake of varied plant phytochemical compounds. A modern diet that reduces these dietary plant defense phytochemicals below levels typical in human evolutionary history may leave humans vulnerable to diseases that were controlled through a foraging diet. Few studies consider the health impact of the recent drastic reduction of plant phytochemical content in the modern global food system, which has eliminated essential components of food because they are not considered "nutrients". The antimicrobial and anti-inflammatory nature of the food system may not only regulate infectious pathogens and inflammatory disease, but also support beneficial microbes in human hosts, reducing vulnerability to chronic diseases. Waorani foragers seem immune to certain infections with very low rates of chronic disease. Does returning to certain characteristics of a foraging food system begin to restore the human body microbe balance and inflammatory response to evolutionary norms, and if so, what implication does this have for the treatment of disease? Several years of data on dietary and health differences across the foragers and the farmers was gathered. There were major differences in health outcomes across the board. In the Waorani forager group there were no signs of infection in serious wounds such as 3rd degree burns and spear wounds. The foragers had one-degree lower body temperature than the farmers. The Waorani had an absence of signs of chronic diseases including vision and blood pressure that did not change markedly with age while Kichwa farmers suffered from both chronic diseases and physiological indicators of aging. In the Waorani forager population, there was an absence of many common regional infectious diseases, from helminthes to staphylococcus. Study design helped control for confounders (exercise, environment, genetic factors, non-phytochemical dietary intake). This study provides evidence of the major role total phytochemical dietary intake plays in human health, often not considered by policymakers and nutritional and agricultural scientists.
ContributorsLondon, Douglas (Author) / Tsuda, Takeyuki (Thesis advisor) / Beezhold, Bonnie L (Committee member) / Hruschka, Daniel (Committee member) / Eder, James (Committee member) / Arizona State University (Publisher)
Created2012
Description
This dissertation is intended to tie together a body of work which utilizes a variety of methods to study applied mathematical models involving heterogeneity often omitted with classical modeling techniques. I posit three cogent classifications of heterogeneity: physiological, behavioral, and local (specifically connectivity in this work). I consider physiological heterogeneity using the method of transport equations to study heterogeneous susceptibility to diseases in open populations (those with births and deaths). I then present three separate models of behavioral heterogeneity. An SIS/SAS model of gonorrhea transmission in a population of highly active men-who-have-sex-with-men (MSM) is presented to study the impact of safe behavior (prevention and self-awareness) on the prevalence of this endemic disease. Behavior is modeled in this examples via static parameters describing consistent condom use and frequency of STD testing. In an example of behavioral heterogeneity, in the absence of underlying dynamics, I present a generalization to ``test theory without an answer key" (also known as cultural consensus modeling or CCM). CCM is commonly used to study the distribution of cultural knowledge within a population. The generalized framework presented allows for selecting the best model among various extensions of CCM: multiple subcultures, estimating the degree to which individuals guess yes, and making competence homogenous in the population. This permits model selection based on the principle of information criteria. The third behaviorally heterogeneous model studies adaptive behavioral response based on epidemiological-economic theory within an $SIR$ epidemic setting. Theorems used to analyze the stability of such models with a generalized, non-linear incidence structure are adapted and applied to the case of standard incidence and adaptive incidence. As an example of study in spatial heterogeneity I provide an explicit solution to a generalization of the continuous time approximation of the Albert-Barabasi scale-free network algorithm. The solution is found by recursively solving the differential equations via integrating factors, identifying a pattern for the coefficients and then proving this observed pattern is consistent using induction. An application to disease dynamics on such evolving structures is then studied.
ContributorsMorin, Benjamin (Author) / Castillo-Chavez, Carlos (Thesis advisor) / Hiebeler, David (Thesis advisor) / Hruschka, Daniel (Committee member) / Suslov, Sergei (Committee member) / Arizona State University (Publisher)
Created2012
Description
Evolution is a key feature of undergraduate biology education: the AmericanAssociation for the Advancement of Science (AAAS) has identified evolution as one of
the five core concepts of biology, and it is relevant to a wide array of biology-related
careers. If biology instructors want students to use evolution to address scientific
challenges post-graduation, students need to be able to apply evolutionary principles to
real-life situations, and accept that the theory of evolution is the best scientific
explanation for the unity and diversity of life on Earth. In order to help students progress
on both fronts, biology education researchers need surveys that measure evolution
acceptance and assessments that measure students’ ability to apply evolutionary concepts.
This dissertation improves the measurement of student understanding and acceptance of
evolution by (1) developing a novel Evolutionary Medicine Assessment that measures
students’ ability to apply the core principles of Evolutionary Medicine to a variety of
health-related scenarios, (2) reevaluating existing measures of student evolution
acceptance by using student interviews to assess response process validity, and (3)
correcting the validity issues identified on the most widely-used measure of evolution
acceptance - the Measure of Acceptance of the Theory of Evolution (MATE) - by
developing and validating a revised version of this survey: the MATE 2.0.
ContributorsMisheva, Anastasia Taya (Author) / Brownell, Sara (Thesis advisor) / Barnes, Elizabeth (Committee member) / Collins, James (Committee member) / Cooper, Katelyn (Committee member) / Sterner, Beckett (Committee member) / Arizona State University (Publisher)
Created2023
Description
Social norms are unwritten behavioral codes. They direct individual behaviors, facilitate interpersonal coordination and cooperation, and lead to variation among human populations. Understanding how norms are maintained and how they change is critical for understanding human evolutionary psychology, social organization, and cultural change. This dissertation uses a mathematical model and a field study to answer two questions: First, what factors determine the content and dynamics of a social norm? Second, how do people make decisions in a normative context? The mathematical model finds that contrary to the popular belief that even arbitrary or deleterious social norms can be maintained once established because deviants suffer coordination failures and social sanctions, norms with continuously varying options cannot be maintained by the pressure to do what others do. Instead, continuous norms evolve to the optimum determined by environmental pressure, individual preferences, or cognitive processes. Therefore, the content of norms across human societies may be less historically constrained than previously assumed. The field study shows that unlike what rational choice theory predicts, people in a small-scale subsistence society do not calculate the ecological and social payoffs of different behaviors in a normative context, even when they have the information to do so. Instead, they rely heavily on social information about what others do. This decision-making algorithm, together with mental categorization that ignores small deviations, and cognitive biases that favor the division prescribed by the norm, maintain an ecologically inefficient and widely disliked cooperative surplus division norm in a Derung village, Dizhengdang, in Yunnan, China.
ContributorsYan, Minhua (Author) / Boyd, Robert (Thesis advisor) / Mathew, Sarah (Thesis advisor) / Hruschka, Daniel (Committee member) / Arizona State University (Publisher)
Created2023
Description
Contact tracing was deployed widely during the COVID-19 pandemic to attempt to stop the spread of SARS Co-V-2. This dissertation investigates the research on contact tracing from a scientometric perspective and looks qualitatively at how case investigators and contact tracers conducted public health practice during the pandemic. Through approaching the public health practice of contact tracing from both a broad, top-down angle, and an on the ground experiential approach, this dissertation provides insight into the issues facing contact tracing as a public health tool.
ContributorsWhite, Alexandra C. (Author) / Jehn, Megan (Thesis advisor) / Hruschka, Daniel (Committee member) / Gaughan, Monica (Committee member) / Arizona State University (Publisher)
Created2022
Description
Latest estimates show that roughly 188 individuals in the United States die everyday due to an opioid-related overdose. This dissertation explores three avenues for
mitigating opioid use disorder (OUD) and the opioid epidemic in the United States (1.)
How can researchers and public health professionals identify areas most in need of
treatment for OUD in an easy-to-use and publicly accessible interface?; (2.) What do
practitioners see as opportunities for reducing barriers to treatment?; and (3.) Why do
differences in opioid mortality exist between demographic groups? To address question
one, I developed an interactive web-based to assist in identifying those counties with the
greatest unmet need of medically assisted treatment (MAT). To answer question two, I
conducted a study of stakeholders (medical providers, peer support specialists, public
health practitioners, etc.) in four New Mexico counties with high unmet need of MAT. to
identify cultural and structural barriers to MAT provision in underserved areas as well as
opportunities for improving access. To answer the third question. I conducted a
systematic review of peer-reviewed literature and government reports to identify how
previous research accounts for race/ethnic and sex disparities in opioid-related
mortality. While many opioid mortality studies show demographic differences, little is
known about why they exist. According to the findings of this systematic review, research
needs to go beyond identifying demographic differences in opioid-related mortality to
understand the reasons for those differences to reduce these inequities.
ContributorsDrake, Alexandria (Author) / Hruschka, Daniel (Thesis advisor) / Jehn, Megan (Committee member) / Scott, Mary Alice (Committee member) / Arizona State University (Publisher)
Created2023
Description
Previous work suggests that lower-income individuals are more likely to engage in mutual aid as a means to manage risk, giving rise to a psychology that is other-oriented, including an empathetic disposition and a proclivity to help people in need. While no study has directly investigated whether helping in times of need increases dispositional empathic concern over time, this assumption is deep-seated among social psychologists. Employing a two-year longitudinal survey of US adults (N = 915), I show that people who experience more needs report helping others when in need a greater number of times, in turn leading to a small but positive increase in their empathetic disposition. This study also identifies the types of needs that elicit empathic concern (i.e., those that arise from unpredictable sources of risk), and shows why cultivating an empathetic disposition is likely to pay off in the long run: those who provide help are more likely to receive help during future times of need. Moreover, this study identifies the types of targets for whom providing help might cultivate an empathetic disposition: those with whom people are likely to share lower interdependence. While previous theoretical frameworks posit that empathic concern selectively directs investment towards interdependent others, providing help to non-interdependent targets might allow people to build positive interdependence with prospective risk pooling partners. Cultivating an empathetic disposition and building interdependence with prospective risk pooling partners can allow people to manage needs that arise from unpredictable sources of risk.
ContributorsGuevara Beltran, Diego (Author) / Aktipis, Athena (Thesis advisor) / Hruschka, Daniel (Committee member) / Kenrick, Douglas (Committee member) / Shiota, Michelle (Committee member) / Arizona State University (Publisher)
Created2023
Description
Similar-identity role models, including instructors, can benefit science undergraduates by enhancing their self-efficacy and sense of belonging. However, for students to have similar-identity role models based on identities that can be hidden, instructors need to disclose their identities. For concealable stigmatized identities (CSIs) – identities that can be hidden and carry negative stereotypes – the impersonal and apolitical culture cultivated in many science disciplines likely makes instructor CSI disclosure unlikely. This dissertation comprises five studies I conducted to assess the presence of instructor role models with CSIs in undergraduate science classrooms and evaluate the impact on undergraduates of instructor CSI disclosure. I find that science instructors report CSIs at lower rates than undergraduates and typically keep these identities concealed. Additionally, I find that women instructors are more likely to disclose their CSIs to students compared to men. To assess the impact of instructor CSI disclosure on undergraduates, I report on findings from a descriptive exploratory study and a controlled field experiment in which an instructor reveals an LGBTQ+ identity. Undergraduates, especially those who also identify as LGBTQ+, benefit from instructor LGBTQ+ disclosure. Additionally, the majority of undergraduate participants agree that an instructor revealing an LGBTQ+ identity during class is appropriate. Together, the results presented in this dissertation highlight the current lack of instructor role models with CSIs and provide evidence of student benefits that may encourage instructors to reveal CSIs to undergraduates and subsequently provide much-needed role models. I hope this work can spark self-reflection among instructors to consider revealing CSIs to students and challenge the assumption that science environments should be devoid of personal identities.
ContributorsBusch, Carly Anne (Author) / Cooper, Katelyn (Thesis advisor) / Brownell, Sara (Thesis advisor) / Collins, James (Committee member) / Zheng, Yi (Committee member) / Arizona State University (Publisher)
Created2024
Description
Education through field exploration is fundamental in geoscience. But not all students enjoy equal access to field-based learning because of time, cost, distance, ability, and safety constraints. At the same time, technological advances afford ever more immersive, rich, and student-centered virtual field experiences. Virtual field trips may be the only practical options for most students to explore pedagogically rich but inaccessible places. A mixed-methods research project was conducted on an introductory and an advanced geology class to explore the implications of learning outcomes of in-person and virtual field-based instruction at Grand Canyon National Park. The study incorporated the Great Unconformity in the Grand Canyon, a 1.2 billion year break in the rock record; the Trail of Time, an interpretive walking timeline; and two immersive, interactive virtual field trips (iVFTs). The in-person field trip (ipFT) groups collectively explored the canyon and took an instructor-guided inquiry hike along the interpretive Trail of Time from rim level, while iVFT students individually explored the canyon and took a guided-inquiry virtual tour of Grand Canyon geology from river level. High-resolution 360° spherical images anchor the iVFTs and serve as a framework for programmed overlays that enable interactivity and allow the iVFT to provide feedback in response to student actions. Students in both modalities received pre- and post-trip Positive and Negative Affect Schedules (PANAS). The iVFT students recorded pre- to post-trip increases in positive affect (PA) scores and decreases in negative (NA) affect scores, representing an affective state conducive to learning. Pre- to post-trip mean scores on concept sketches used to assess visualization and geological knowledge increased for both classes and modalities. However, the iVFT pre- to post-trip increases were three times greater (statistically significant) than the ipFT gains. Both iVFT and ipFT students scored 92-98% on guided-inquiry worksheets completed during the trips, signifying both met learning outcomes. Virtual field trips do not trump traditional in-person field work, but they can meet and/or exceed similar learning objectives and may replace an inaccessible or impractical in-person field trip.
ContributorsRuberto, Thomas (Author) / Semken, Steve (Thesis advisor) / Anbar, Ariel (Committee member) / Brownell, Sara (Committee member) / Arizona State University (Publisher)
Created2018
Description
Background In the United States (US), first-year university students typically live on campus and purchase a meal plan. In general, meal plans allow the student a set number of meals per week or semester, or unlimited meals. Understanding how students’ use their meal plan, and barriers and facilitators to meal plan use, may help decrease nutrition-related issues.
Methods First-year students’ meal plan and residence information was provided by a large, public, southwestern university for the 2015-2016 academic year. A subset of students (n=619) self-reported their food security status. Logistic generalized estimating equations (GEEs) were used to determine if meal plan purchase and use were associated with food insecurity. Linear GEEs were used to examine several potential reasons for lower meal plan use. Logistic and Linear GEEs were used to determine similarities in meal plan purchase and use for a total of 599 roommate pairs (n=1186 students), and 557 floormates.
Results Students did not use all of the meals available to them; 7% of students did not use their meal plan for an entire month. After controlling for socioeconomic factors, compared to students on unlimited meal plans, students on the cheapest meal plan were more likely to report food insecurity (OR=2.2, 95% CI=1.2, 4.1). In Fall, 26% of students on unlimited meal plans reported food insecurity. Students on the 180 meals/semester meal plan who used fewer meals were more likely to report food insecurity (OR=0.9, 95% CI=0.8, 1.0); after gender stratification this was only evident for males. Students’ meal plan use was lower if the student worked a job (β=-1.3, 95% CI=-2.3, -0.3) and higher when their roommate used their meal plan frequently (β=0.09, 99% CI=0.04, 0.14). Roommates on the same meal plan (OR=1.56, 99% CI=1.28, 1.89) were more likely to use their meals together.
Discussion This study suggests that determining why students are not using their meal plan may be key to minimizing the prevalence of food insecurity on college campuses, and that strategic roommate assignments may result in students’ using their meal plan more frequently. Students’ meal plan information provides objective insights into students’ university transition.
Methods First-year students’ meal plan and residence information was provided by a large, public, southwestern university for the 2015-2016 academic year. A subset of students (n=619) self-reported their food security status. Logistic generalized estimating equations (GEEs) were used to determine if meal plan purchase and use were associated with food insecurity. Linear GEEs were used to examine several potential reasons for lower meal plan use. Logistic and Linear GEEs were used to determine similarities in meal plan purchase and use for a total of 599 roommate pairs (n=1186 students), and 557 floormates.
Results Students did not use all of the meals available to them; 7% of students did not use their meal plan for an entire month. After controlling for socioeconomic factors, compared to students on unlimited meal plans, students on the cheapest meal plan were more likely to report food insecurity (OR=2.2, 95% CI=1.2, 4.1). In Fall, 26% of students on unlimited meal plans reported food insecurity. Students on the 180 meals/semester meal plan who used fewer meals were more likely to report food insecurity (OR=0.9, 95% CI=0.8, 1.0); after gender stratification this was only evident for males. Students’ meal plan use was lower if the student worked a job (β=-1.3, 95% CI=-2.3, -0.3) and higher when their roommate used their meal plan frequently (β=0.09, 99% CI=0.04, 0.14). Roommates on the same meal plan (OR=1.56, 99% CI=1.28, 1.89) were more likely to use their meals together.
Discussion This study suggests that determining why students are not using their meal plan may be key to minimizing the prevalence of food insecurity on college campuses, and that strategic roommate assignments may result in students’ using their meal plan more frequently. Students’ meal plan information provides objective insights into students’ university transition.
Contributorsvan Woerden, Irene (Author) / Bruening, Meg (Thesis advisor) / Hruschka, Daniel (Committee member) / Schaefer, David (Committee member) / Vega-Lopez, Sonia (Committee member) / Adams, Marc (Committee member) / Arizona State University (Publisher)
Created2019