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- Member of: ASU Electronic Theses and Dissertations
Description
Anthropogenic land use has irrevocably transformed the natural systems on which humankind relies. Understanding where, why, and how social and economic processes drive globally-important land-use changes, from deforestation to urbanization, has advanced substantially. Illicit and clandestine activities--behavior that is intentionally secret because it breaks formal laws or violates informal norms--are poorly understood, however, despite the recognition of their significant role in land change. This dissertation fills this lacuna by studying illicit and clandestine activity and quantifying its influence on land-use patterns through examining informal urbanization in Mexico City and deforestation Central America. The first chapter introduces the topic, presenting a framework to examine illicit transactions in land systems. The second chapter uses data from interviews with actors involved with land development in Mexico City, demonstrating how economic and political payoffs explain the persistence of four types of informal urban expansion. The third chapter examines how electoral politics influence informal urban expansion and land titling in Mexico City using panel regression. Results show land title distribution increases just before elections, and more titles are extended to loyal voters of the dominant party in power. Urban expansion increases with electoral competition in local elections for borough chiefs and legislators. The fourth chapter tests and confirms the hypothesis that narcotrafficking has a causal effect on forest loss in Central America from 2001-2016 using two proxies of narcoactivity: drug seizures and events from media reports. The fifth chapter explores the spatial signature and pattern of informal urban development. It uses a typology of urban informality identified in chapter two to hypothesize and demonstrate distinct urban expansion patterns from satellite imagery. The sixth and final chapter summarizes the role of illicit and clandestine activity in shaping deforestation and urban expansion through illegal economies, electoral politics, and other informal transactions. Measures of illicit and clandestine activity should--and could--be incorporated into land change models to account for a wider range of relevant causes. This dissertation shines a new light on the previously hidden processes behind ever-easier to detect land-use patterns as earth observing satellites increase spatial and temporal resolution.
ContributorsTellman, Elizabeth (Author) / Turner II, Billie L (Thesis advisor) / Eakin, Hallie (Thesis advisor) / Janssen, Marco (Committee member) / Alba, Felipe de (Committee member) / Jain, Meha (Committee member) / Arizona State University (Publisher)
Created2019
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
Description
Salad bars are promoted as a means to increase fruit and vegetable consumption among school-age children; however, no study has assessed barriers to having salad bars. Further, it is not known if barriers differ across school level. This cross-sectional study investigated the barriers to having salad bars across school level among schools without salad bars in Arizona (n=177). Multivariate binominal regression models were used to determine differences between the barriers and school level, adjusting for years at current job, enrollment of school, free-reduced eligibility rate and district level clustering. The top five barriers were not enough staff (51.4%), lack of space for salad bars (49.7%), food waste concerns (37.9%), sanitation/food safety concerns (31.3%), and time to get through the lines (28.3%) Adjusted analyses indicated two significant differences between barriers across school level: time to get through lines (p=0.040) and outside caterer/vendor (p=0.018) with time to get through lines reported more often by elementary and middle school nutrition managers and outside caterer/vendor reported most often by high school nutrition managers. There were several key barriers reported and results indicate that having an outside vendor/caterer for their meal programs and time to get through the service lines varied across school level. High schools report a higher percent of the barrier outside caterer/vendors and elementary and middle schools report a higher percent of the barrier time to get through the lines. Results indicate that research determining the approximate time it takes students to get through salad bar lines will need to be considered. More research is needed to determine if the barrier time to get through the service lines is due to selection of food items or if it is due to the enrollment size of the lunch period. Future research interventions may consider investigating food safety and sanitation concerns of middle school nutrition managers. Findings may be used to guide ways to decrease barriers in schools without salad bars.
ContributorsKebric, Kelsey (Author) / Bruening, Meg (Thesis advisor) / Ohri-Vachaspati, Punam (Committee member) / Adams, Marc (Committee member) / Arizona State University (Publisher)
Created2016
Description
This dissertation examines the various factors and processes that have been proposed as explanations for the spread of agriculture in the west Mediterranean. The expansion of the Neolithic in the west Mediterranean (the Impresso-Cardial Neolithic) is characterized by a rapid spread of agricultural subsistence and material culture from the southern portion of the Italian peninsula to the western coast of the Iberian peninsula. To address this unique case, four conceptual models of Neolithic spread have been proposed: the Wave of Advance, the Capillary Spread Model, the Maritime Pioneer Colonization Model and the Dual Model. An agent-based model, the Cardial Spread Model, was built to simulate each conceptual spread model in a spatially explicit environment for comparison with evidence from the archaeological record. Chronological information detailing the arrival of the Neolithic was used to create a map of the initial arrival of the Neolithic (a chronosurface) throughout the study area. The results of each conceptual spread model were then compared to the chronosurface in order to evaluate the relative performance of each conceptual model of spread. These experiments suggest that both the Dual and Maritime Pioneer Colonization models best fit the available chronological and spatial distribution of the Impresso-Cardial Neolithic.
For the purpose of informing agent movement and improving the fit of the conceptual spread models, a variety of paleoenvironmental maps were tested within the Cardial Spread Model. The outcome of these experiments suggests that topographic slope was an important factor in settlement location and that rivers were important vectors of transportation for early Neolithic migration. This research demonstrates the application of techniques rare to archaeological analysis, agent-based modeling and the inclusion of paleoenvironmental information, and provides a valuable tool that future researchers can utilize to further evaluate and fabricate new models of Neolithic expansion.
For the purpose of informing agent movement and improving the fit of the conceptual spread models, a variety of paleoenvironmental maps were tested within the Cardial Spread Model. The outcome of these experiments suggests that topographic slope was an important factor in settlement location and that rivers were important vectors of transportation for early Neolithic migration. This research demonstrates the application of techniques rare to archaeological analysis, agent-based modeling and the inclusion of paleoenvironmental information, and provides a valuable tool that future researchers can utilize to further evaluate and fabricate new models of Neolithic expansion.
ContributorsBergin, Sean M (Author) / Barton, Michael (Thesis advisor) / Janssen, Marco (Committee member) / Coudart, Anick (Committee member) / Arizona State University (Publisher)
Created2016
Description
The closer integration of the world economy has yielded many positive benefits including the worldwide diffusion of innovative technologies and efficiency gains following the widening of international markets. However, closer integration also has negative consequences. Specifically, I focus on the ecology and economics of the spread of species and pathogens. I approach the problem using theoretical and applied models in ecology and economics. First, I use a multi-species theoretical network model to evaluate the ability of dispersal to maintain system-level biodiversity and productivity. I then extend this analysis to consider the effects of dispersal in a coupled social-ecological system where people derive benefits from species. Finally, I estimate an empirical model of the foot and mouth disease risks of trade. By combining outbreak and trade data I estimate the disease risks associated with the international trade in live animals while controlling for the biosecurity measures in place in importing countries and the presence of wild reservoirs. I find that the risks associated with the spread and dispersal of species may be positive or negative, but that this relationship depends on the ecological and economic components of the system and the interactions between them.
ContributorsShanafelt, David William (Author) / Perrings, Charles (Thesis advisor) / Fenichel, Eli (Committee member) / Richards, Timorthy (Committee member) / Janssen, Marco (Committee member) / Collins, James (Committee member) / Arizona State University (Publisher)
Created2016
Description
Background: Childhood obesity is one of the most serious public health concerns in the United States and has been associated with low levels of physical activity. Schools are ideal physical activity promotion sites but school physical activity opportunities have decreased due the increased focus on academic performance. Before-school programs provide a good opportunity for children to engage in physical activity as well as improve their readiness to learn. Purpose: The purpose of this study was to examine the effect of a before-school running/walking club on children's physical activity and on-task behavior. Methods: Participants were third and fourth grade children from two schools in the Southwestern United States who participated in a before-school running/walking club that met two times each week. The study employed a two-phase experimental design with an initial baseline phase and an alternating treatments phase. Physical activity was monitored using pedometers and on-task behavior was assessed through systematic observation. Data analysis included visual analysis, descriptive statistics, as well as multilevel modeling. Results: Children accumulated substantial amounts of physical activity within the before-school program (School A: 1731 steps, 10:02 MVPA minutes; School B: 1502 steps, 8:30 MVPA minutes) and, on average, did not compensate by decreasing their physical activity during the rest of the school day. Further, on-task behavior was significantly higher on days the children attended the before-school program than on days they did not (School A=15.78%, pseudo-R2=.34 [strong effect]; School B=14.26%, pseudo-R2=.22 [moderate effect]). Discussion: Results provide evidence for the positive impact of before-school programs on children's physical activity and on-task behavior. Such programs do not take time away from academics and may be an attractive option for schools.
ContributorsStylianou, Michalis (Author) / Kulinna, Pamela H. (Thesis advisor) / Van Der Mars, Hans (Committee member) / Amazeen, Eric (Committee member) / Adams, Marc (Committee member) / Mahar, Matthew T. (Committee member) / Arizona State University (Publisher)
Created2014
Effect of a Wii Fit® intervention on balance, muscular fitness, and bone health in middle-aged women
Description
Sustaining a fall can be hazardous for those with low bone mass. Interventions exist to reduce fall-risk, but may not retain long-term interest. "Exergaming" has become popular in older adults as a therapy, but no research has been done on its preventative ability in non-clinical populations. The purpose was to determine the impact of 12-weeks of interactive play with the Wii Fit® on balance, muscular fitness, and bone health in peri- menopausal women. METHODS: 24 peri-menopausal-women were randomized into study groups. Balance was assessed using the Berg/FICSIT-4 and a force plate. Muscular strength was measured using the isokinetic dynamometer at 60°/180°/240°/sec and endurance was assessed using 50 repetitions at 240°/sec. Bone health was tracked using dual-energy x-ray absorptiometry (DXA) for the hip/lumbar spine and qualitative ultrasound (QUS) of the heel. Serum osteocalcin was assessed by enzyme immunoassay. Physical activity was quantified using the Women's Health Initiative Physical Activity Questionnaire and dietary patterns were measured using the Nurses' Health Food Frequency Questionnaire. All measures were repeated at weeks 6 and 12, except for the DXA, which was completed pre-post. RESULTS: There were no significant differences in diet and PA between groups. Wii Fit® training did not improve scores on the Berg/FICSIT-4, but improved center of pressure on the force plate for Tandem Step, Eyes Closed (p-values: 0.001-0.051). There were no significant improvements for muscular fitness at any of the angular velocities. DXA BMD of the left femoral neck improved in the intervention group (+1.15%) and decreased in the control (-1.13%), but no other sites had significant changes. Osteocalcin indicated no differences in bone turnover between groups at baseline, but the intervention group showed increased bone turnover between weeks 6 and 12. CONCLUSIONS: Findings indicate that WiiFit® training may improve balance by preserving center of pressure. QUS, DXA and osteocalcin data confirm that those in the intervention group were experiencing more bone turnover and bone formation than the control group. In summary, twelve weeks of strength /balance training with the Wii Fit® shows promise as a preventative intervention to reduce fall and fracture risk in non-clinical middle aged women who are at risk.
ContributorsWherry, Sarah Jo (Author) / Swan, Pamela D (Thesis advisor) / Adams, Marc (Committee member) / Der Ananian, Cheryl (Committee member) / Sweazea, Karen (Committee member) / Vaughan, Linda (Committee member) / Arizona State University (Publisher)
Created2014
Description
The coordination of group behavior in the social insects is representative of a broader phenomenon in nature, emergent biological complexity. In such systems, it is believed that large-scale patterns result from the interaction of relatively simple subunits. This dissertation involved the study of one such system: the social foraging of the ant Temnothorax rugatulus. Physically tiny with small population sizes, these cavity-dwelling ants provide a good model system to explore the mechanisms and ultimate origins of collective behavior in insect societies. My studies showed that colonies robustly exploit sugar water. Given a choice between feeders unequal in quality, colonies allocate more foragers to the better feeder. If the feeders change in quality, colonies are able to reallocate their foragers to the new location of the better feeder. These qualities of flexibility and allocation could be explained by the nature of positive feedback (tandem run recruitment) that these ants use. By observing foraging colonies with paint-marked ants, I was able to determine the `rules' that individuals follow: foragers recruit more and give up less when they find a better food source. By altering the nutritional condition of colonies, I found that these rules are flexible - attuned to the colony state. In starved colonies, individual ants are more likely to explore and recruit to food sources than in well-fed colonies. Similar to honeybees, Temmnothorax foragers appear to modulate their exploitation and recruitment behavior in response to environmental and social cues. Finally, I explored the influence of ecology (resource distribution) on the foraging success of colonies. Larger colonies showed increased consistency and a greater rate of harvest than smaller colonies, but this advantage was mediated by the distribution of resources. While patchy or rare food sources exaggerated the relative success of large colonies, regularly (or easily found) distributions leveled the playing field for smaller colonies. Social foraging in ant societies can best be understood when we view the colony as a single organism and the phenotype - group size, communication, and individual behavior - as integrated components of a homeostatic unit.
ContributorsShaffer, Zachary (Author) / Pratt, Stephen C (Thesis advisor) / Hölldobler, Bert (Committee member) / Janssen, Marco (Committee member) / Fewell, Jennifer (Committee member) / Liebig, Juergen (Committee member) / Arizona State University (Publisher)
Created2014
Description
Research indicates that adults are not acquiring enough physical activity. Increasing the use of stairs is an accessible way to weave high intensity physical activity into the daily routine. The purpose of this study is to test the effect of four environmental changes on ascending stair use in a mixed population of college students, faulty, and staff on a southwest college campus. The study design included a 10-week time series design with alternating baseline and intervention phases, including a directional cue represented by footprints on the ground, a positive prompt, a deterrent prompt and a combination phase. Data was collected with both an in-person tally and a video recording device. The study included 6,140 observations and coded variables included stair use, sex, number of bags carried, temperature, and volume. Rater reliability ranged from .81 to 1.0. Multivariate logistic regression was used to perform the statistic analysis. Stair use increased significantly from Washout 1 and the positive prompting phase with a 7% absolute increase and an odds ratio of 1.35 (95% CI 1.080-1.696). Stair use during the footprint phase, deterrent phase and combination phase did not increase significantly compared to the previous baseline or washout phases. Day of the week (Monday=reference, Tuesday CI=1.626, 95% CI 1.298-2.011, Wednesday OR=0.457, 95% CI 0.248-0.841, Thursday OR=1.434, 95% CI 1.164-1.766), sex (OR=1.376, 95% CI 1.173-1.613) and volume (OR=1.007, 95% CI 1.005-1.008) were significantly correlated to stair use. Women used the stairs more than men and higher volume situations were related to increased stair use. Temperature and baggage number were not related to stair use. The results of this study indicate that positive prompting with an environmental message theme is an effective method to increase stair use in a university setting.
ContributorsFord, Marley (Author) / Adams, Marc (Thesis advisor) / Der Ananian, Cheryl (Committee member) / Vaughan, Linda (Committee member) / Arizona State University (Publisher)
Created2015
Description
In Latin America food insecurity is still prevailing in those regions where extreme poverty and political instability are common. Tseltal communities are experiencing changes due to religious conversions and the incursion of external political institutions. These changes have diminished the importance of traditional reciprocal and redistributive institutions that historically have been essential for personal and community survival. This dissertation investigated the impact that variations on governance systems and presence of reciprocal and distributional exchanges have on the food security status of communities. Qualitative data collected in four communities through 117 free lists and 117 semi-structured interviews was used to elaborate six scales that correspond to the traditional and civic authority system and to inter-community and intra-community reciprocity and redistribution. I explore the relationship that the scores of four communities on those scales have on the food security status of their inhabitants based on their results on the National Health and Nutrition Survey 2012. Findings from this study suggest that in marginalized communities that many scientists would described as experiencing market failure, participation in inter-community reciprocal, intra-community reciprocal and intra-community redistribution are better predictors of food security than enrollment in food security programs. Additionally, communities that participated the most in these non-market mechanisms have stronger traditional institutions. In contrast, communities that participated more in inter-community redistribution scored higher on the civic authority scale, are enrolled in more food aid programs, but are less food secure.
ContributorsDe La Torre Pacheco, Sindy Yaneth (Author) / Janssen, Marco (Thesis advisor) / Eakin, Hallie (Committee member) / BurnSilver, Shauna (Committee member) / Arizona State University (Publisher)
Created2015