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Pollution, extreme weather, and global warming have become increasingly important in today’s society. This dissertation examines these topics in three chapters, analyzing the effects of pollution and environmental factors on human behavior. The first chapter uses a dataset of unique daily crimes in the U.S. to unveil the relationship between weather/pollution and the crime rate for seven major U.S. cities. The results reveal that temperature significantly affects both violent and property crime rates. The rate of violent crime is lower on extreme and unpleasant weather days (i.e., when the temperature is above 99°F) in comparison to good or unremarkable days. There is little evidence on how air pollution affects the crime rate by using fine particulates (PM2.5) and coarse particulates (PM10). However, pollution does have an effect on crime if the area of analysis is located closer to an operated toxic release facility. The second chapter examines how weekly hours worked by individuals vary with respect to snowfall in 265 metropolitan areas (about 75% of the US workforce) over the years 2004-2014. The results reveal that working hours are significantly affected by snow events, with magnitudes varying by types of workers, types of employment (class of worker, occupation, and industry), and regions. Overall, each average daily inch of snowfall, during a Current Population Survey (CPS) monthly reference week, reduces working hours by about 1 hour. Snow storms reduce weekly hours worked considerably more among construction workers and in the South than elsewhere in the U.S.. We find little evidence that hours lost from large snowfalls are “made-up” in subsequent weeks. The third chapter investigates whether housing age, which has been missing in the conventional environmental justice literature, has an impact on the distribution of households in a pollution area. Income and race were believed to be predominant factors that affect the location choices of individuals. By controlling for this additional housing age variable in the conventional model, I examine which factor, income or race, is affected most. The results indicate that older houses are located closer to pollution sites. Additionally, once I control for the housing age, the marginal effect of income declines significantly, approximately by 50%. The effect on race was insignificant in empirical analysis.

There are many factors that affect the hours worked by various professions. The literature discusses some of these factors in professions such as management and various fields of medicine. However, no information has been gathered on factors that affect the practice of dentists. A survey was disseminated to all Iowa dentists inquiring about various factors that may affect the number of hours they spend at work. The survey inquired about demographics, educational indebtedness, caregiving responsibilities of both children and dependent adults, contribution to household income, relationship status, domestic responsibilities, busyness and type of practice. The data was collected and analyzed. It was hypothesized that there was no difference in the number of hours worked between male and female Iowa dentists and there was no difference in the number of hours worked between female Iowa dentists with minor children (18 years old or younger) and female dentists without minor children. When hypotheses were statistically analyzed, the data showed there was no difference between male and female dentists' working hours in the bivariate analysis. In the multiple logistic regression model, while controlling for various factors such as age and busyness, gender was statistically significant in the number of hours worked. When evaluating the hours worked between female dentists with and without minors, there was a statistically significant difference in the number of hours worked between women with minor children and women without minors. However, in the multiple logistic regression model, presence of minors was not statistically significant. This lack of statistical significance is likely attributed to the small sample size of women dentists. As such, there was not enough power to have more than 2 variables and minor children was not included. The data suggests that young male dentists, who are responsible for 61% or more of their household income and are solo practitioners are the most likely to work full-time (32+ hours/week).

The purpose of this study was to determine the effects of a simulation with workedexamples on the creation of episodic memories and the troubleshooting ability of maintenance technician students. Previous research shows that domain knowledge, conceptual knowledge, strategic knowledge, and episodic memories are all required to successfully troubleshoot. While domain, conceptual, and strategic knowledge can all be taught using traditional instruction, episodic memories require students to experience the actual troubleshooting of a fault. Simulations and worked examples are two instructional methods that have proven effective at teaching troubleshooting. This research specifically examined how a simulation combined with worked examples would affect 1) immediate troubleshooting abilities, 2) the creation of episodic memories, and 3) delayed troubleshooting abilities. This study was conducted in two stages and administered via a learning management system due to COVID-19 restrictions. The first stage included a pre-test, a training session using the simulation with worked examples, and an immediate post-test for near and far transfer of troubleshooting abilities. The second stage occurred one week later and included the final posttest for near and far transfer of troubleshooting abilities and creation of episodic memories. Answers to four troubleshooting questions on each of the pre-test and immediate and delayed post-tests were collected to determine any differences in the immediate and retained troubleshooting abilities. Answers to the solution mapping questions were collected to determine the creation of episodic memories. A repeated measure analysis of variance was conducted in SPSS to analyze the results of the troubleshooting pre- and post-tests. A correlational coefficient was used to determine any interaction between episodic memories and delayed troubleshooting abilities. Previous experience levels and participants’ major of study were also examined to determine their effect on the results. The findings show the simulation with worked examples had a statistically significant effect on delayed troubleshooting abilities and the created episodic memories had a positive correlation with the delayed troubleshooting, both with a medium effect size. However, the simulation with worked examples had no statistically significant effect on immediate troubleshooting abilities. Levels of previous experience and participants’ major of study had little effect on the results.

Informed parent advocates are essential to planning the educational outcomes of their children with special needs in the K through 12 public school system. However, inappropriate instructional techniques used in advocacy training may reduce trainees' learning outcomes by adding complexity and increasing cognitive load. This study examined whether using worked examples to break down complex problems into component parts to build long term schema could lower cognitive load and thus improve learning outcomes for parent advocacy trainees. Based on cognitive load theory, this 2 x 3 factorial design study examined the efficacy of noninteractive video lessons for parent trainees using worked examples to reduce extraneous cognitive load. Research questions explored the relationships between the independent variables of using worked examples and parents' perceived class relevance on the dependent variable, change in cognitive load of parent trainees, as well as the interaction between training type and perceived class relevance. Two groups of 65 adults in advocacy training (N = 130) participated in a video lesson in either the worked examples or nonworked examples format as part of their advocacy training. The NASA Task Load Index and the Perceived Class Relevance Survey instruments were used to measure cognitive load of trainees and perceptions of training relevance. Key findings included a significant main effect between the use of worked examples and change in cognitive load and significant interaction effects with the perception of class relevance. Training was developed for advocacy trainers in the use of worked examples for learners new to a domain. Implications for social change include improved learning outcomes for parents who must learn IEP terminology in beginning classes to effectively advocate for their children.

This study was designed to compare the effects of the use of worked examples and self-explanation on motivation for male and female students. More specifically, the present study examines whether there are differences between males and females with regards to their achievement goals and if gender plays a role in how students respond to questions about their motivation in the presence of other male or female students. Comparisons of student responses on Achievement Goal Questionnaire-Revised (AGQ-R) and the Patterns of Adaptive Learning Scales (PALS) were also conducted. Participants were 147 seventh-, eighth- and ninth-grade non-honors Algebra I students (82 girls and 65 boys) from three schools and eight classrooms within the same school district on the east cost of the United States of America. Results replicated the finding that females have more mastery goals than males, however no gender differences were found for either performance. In addition, it appears that students respond differently to some questions about their motivation in the presence of other male or female students. Finally, the AGQ-R and the PALS appear to be consistent representations of students' achievement goals. / School Psychology

This analysis of faunal bones from Wolf Village focuses on large game and its utility, as evidenced by what is known as the modified general utility index (MGUI). The MGUI proposes that bones at sites reflect transportation and butchering choices made by hunters at kill-butchering sites. According to the assumptions associated with the MGUI, hunters should select animal portions with high food value. The MGUI has been used in Fremont archaeology to provide a rough measure of site function. The expectation is that faunal bones would accompany the prized cuts of large game meat at habitation sites – and the animal parts with little food value would remain at kill-butchering sites because they are not worth the cost to carry them to the village. My analysis of large game animal bones found in excavations at Wolf Village counter these expectations. Fremont hunters at Wolf Village were returning to the site with low-caloric portions of large game, at least part of the time. Results from strontium isotope analysis suggest that many of the large game individuals hunted by the Fremont were not local to the immediate area. This suggests that hunters saw utility in low-caloric elements not related only to food value. Some low-caloric skeletal elements were used by the Fremont to construct bone tools and other objects, and as possible symbolic objects used in abandonment rituals. The results of this research suggests that the MGUI is not appropriate for measuring the utility of animal portions to the Fremont. Only when considering the social and non-caloric economic reasons for transporting low caloric elements, can archaeologists discover the true utility of large game animal parts to Fremont hunters.

Learning from worked examples typically involves study activities, involving reading such materials carefully and attempting to understand the information presented. Considerable evidence has amassed regarding the benefits for novices of studying appropriately constructed worked examples paired with practice questions. However, prior research from the cognitive and sports psychology literatures suggests mental practice of worked examples may be an effective adjunct to studying such materials. Meta-analyses of these literatures suggest the utility of mental practice depends upon the degree of cognitive elements contained within a task, and also suggest that some prior knowledge of a task is necessary for mental practice to be effective. The present series of studies aimed to identify conditions under which mental practice is effective in educationally realistic, highly cognitive domains. Based on the above meta-analytic results, mental practice was hypothesised to enhance learning over further study in highly cognitive domains, but only when students either had sufficient prior knowledge, or were able to develop such knowledge over the course of an instructional intervention. Study activities were primarily expected to support knowledge acquisition, while imagining-based activities (mental practice) were expected to support knowledge automation. The experiments herein thus investigated interactions between levels of prior knowledge, complexity of instructional material, and levels of learning from imagination versus conventional study strategies. In Experiment 1, under conditions of low prior knowledge and complex material (HTML), students who studied worked examples outperformed those who imagined. Experiment 2, using simplified but still complex materials and a similar participant pool, found no differences between conditions, but Experiment 3, using stricter experimental design, found a study effect. In Experiment 4, an imagination effect was found under high prior knowledge. Experiment 5, using less experienced learners, suggested those who studied outperformed those whom imagined on acquisition questions. Experiment 6 found a sequence of study then imagination is more effective than imagination then study. The results have broad application for effective sequencing of these instructional strategies, but development of an accurate metric for imagination "readiness" is required to advance theory and practice, and more evidence is needed for a schema automation explanation of mental practice effects.

The successful use of Nickel-Titanium (Nitinol) in biomedical applications requires an accurate control of its unique mechanical properties. The purpose of this study is to analyze the effects of a wide range of heat treatments on the mechanical behavior of hot-rolled and cold-drawn Nitinol. Results comprise an understanding of the effect of heat treatment temperature and time variation on final material response which is imperative for optimization of material properties. Thirty-three heat treatment variations are tested by combining three durations, 10 minutes, 90 minutes, and 8 hours, with eleven different heat treatment temperatures between 200°C and 440°C. Following heat treatment, the Nitinol samples undergo tensile testing with upper plateau strength, lower plateau strength, ultimate tensile strength, strain to failure, and residual elongation compared for all test groups. Heat treatment "power" is used to describe the efficacy of different combinations of heat treatment temperature and duration. When using hot-rolled Nitinol, results show a low heat treatment power does not create significant precipitation hardening or a significant decrease in martensite transformation stress, resulting in a high upper plateau strength, high residual strain values, and evidence of plastic deformation upon unloading. Moderate power treatments lead to sufficient hardening of the material and a decrease in martensite transformation stress resulting in a pseudoelastic response. Increasing to a high treatment power further decreases the transformation stress and increases the martensite transformation temperature leading to a shape-memory response in hot rolled Nitinol. When using cold-drawn Nitinol, low and moderate heat treatment power levels result in the material exhibiting a pseudoelastic response. Increasing heat treatment power shows the same effects on martensite transformation stress and temperature as seen with the hot-rolled material resulting in a material response transition from pseudoelastic to shape memory.

Silos metálicos para armazenagem de diferentes tipos de produto são muito empregados no Brasil, isso faz com que compreender melhor o funcionamento deste tipo de sistemas estrutural possa levar a soluções mais inteligentes e econômicas. Com esse intuito no presente trabalho estudam-se as colunas de sustentação de um tipo de silo metálico para armazenagem de ração animal. Neste estudo as colunas foram analisadas seguindo as determinações da norma brasileira de dimensionamento de perfis conformados a frio e com modelos numéricos de diferentes níveis de complexidade. Primeiramente se estudou o perfil conformado a frio utilizado nas colunas dos silos através do método das faixas finitas e obtiveram-se as forças axiais de flambagem local e distorcional elástica. Estes valores foram utilizados no método da resistência direta para obtenção dos índices de esbeltez associados a estes modos de flambagem. Foram definidas as forças axiais de colapso, seguindo as metodologias da norma ABNT NBR 14762:2010 (método das larguras efetivas, seção efetiva e resistência direta) para diversos comprimentos do perfil. Foi desenvolvido um modelo numérico para cálculo via método dos elementos finitos, considerando não linearidades materiais e geométricas e imperfeições geométricas iniciais. Os resultados obtidos através deste modelo numérico foram comparados com os obtidos através da norma ABNT NBR 14762:2010. Após ajuste do modelo numérico se realizou um estudo paramétrico para conhecer a influência da rigidez de fixação, entre a coluna de sustentação e o corpo silo, na força de colapso do perfil. São aplicadas diversas condições de contorno com o objetivo de aproximar o modelo numérico das condições reais de fixação da coluna. Finalmente os resultados obtidos são utilizados para determinar a relação entre a força resistente do perfil e a força solicitante na coluna do silo segundo as condições usuais de segurança referentes aos estados-limites últimos determinados pela ABNT NBR 14762:2010. / Tubular steel silos for storage of different product types are widely used in Brazil. The knowledge of these structural systems can result to smarter and economic solutions. In this work is studied the structural columns of some bulk feed tanks with the national standard design code and numeric models with several complexity level. First were studied the cold-formed steel member used in the silo’s columns with the finite strip methods, and were obtained the elastic local/distorcional buckling axial forces. These values were used with the Direct Strength Method to find out slenderness ratios associated with these modes of buckling. The axial collapse forces were defined following the conception of standard ABNT NBR 14762:2010(using the methods of effective width, effective section and direct resistance) for several members’ lengths. A numeric model was development to calculate with finite elements method, considering materials and geometrics nonlinearities with initial geometric imperfections. The results obtained by this numeric model were compared with those obtained by the standard ABNT NBR 14762:2010. After the numeric model adjust, a parametric study was made to know the influences of the connection stiffness between the column and the silo’s cylindrical wall, in the member’s allowable axial strength. Several boundary conditions were applied with the main purpose to approximate the numeric model with the actual columns' end conditions. Finally the obtained results were used to determine the ration between the axial allowable strength and the required load on the silo’s columns by the usual safety conditions using the ultimate limit state determined by the ABNT NBR 14762:2010.