Matching Items (79)
Filtering by
- Resource Type: Text
Description
Accumulating evidence implicates exposure to adverse childhood experiences in the development of hypocortisolism in the long-term, and researchers are increasingly examining individual-level mechanisms that may underlie, exacerbate or attenuate this relation among at-risk populations. The current study takes a developmentally and theoretically informed approach to examining episodic childhood stressors, inherent and voluntary self-regulation, and physiological reactivity among a longitudinal sample of youth who experienced parental divorce. Participants were drawn from a larger randomized controlled trial of a preventive intervention for children of divorce between the ages of 9 and 12. The current sample included 159 young adults (mean age = 25.5 years; 53% male; 94% Caucasian) who participated in six waves of data collection, including a 15-year follow-up study. Participants reported on exposure to negative life events (four times over a 9-month period) during childhood, and mothers rated child temperament. Six years later, youth reported on the use of active and avoidant coping strategies, and 15 years later, they participated in a standardized psychosocial stress task and provided salivary cortisol samples prior to and following the task. Path analyses within a structural equation framework revealed that a multiple mediation model best fit the data. It was found that children with better mother-rated self-regulation (i.e. low impulsivity, low negative emotionality, and high attentional focus) exhibited lower total cortisol output 15 years later. In addition, greater self-regulation in childhood predicted greater use of active coping in adolescence, whereas a greater number of negative life events predicted increased use of avoidant coping in adolescence. Finally, a greater number of negative events in childhood predicted marginally lower total cortisol output, and higher levels of active coping in adolescence were associated with greater total cortisol output in young adulthood. Findings suggest that children of divorce who exhibit better self-regulation evidence lower cortisol output during a standardized psychosocial stress task relative to those who have higher impulsivity, lower attentional focus, and/or higher negative emotionality. The conceptual significance of the current findings, including the lack of evidence for hypothesized relations, methodological issues that arose, and issues in need of future research are discussed.
ContributorsHagan, Melissa (Author) / Luecken, Linda (Thesis advisor) / MacKinnon, David (Committee member) / Wolchik, Sharlene (Committee member) / Doane, Leah (Committee member) / Arizona State University (Publisher)
Created2013
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
In order to analyze data from an instrument administered at multiple time points it is a common practice to form composites of the items at each wave and to fit a longitudinal model to the composites. The advantage of using composites of items is that smaller sample sizes are required in contrast to second order models that include the measurement and the structural relationships among the variables. However, the use of composites assumes that longitudinal measurement invariance holds; that is, it is assumed that that the relationships among the items and the latent variables remain constant over time. Previous studies conducted on latent growth models (LGM) have shown that when longitudinal metric invariance is violated, the parameter estimates are biased and that mistaken conclusions about growth can be made. The purpose of the current study was to examine the impact of non-invariant loadings and non-invariant intercepts on two longitudinal models: the LGM and the autoregressive quasi-simplex model (AR quasi-simplex). A second purpose was to determine if there are conditions in which researchers can reach adequate conclusions about stability and growth even in the presence of violations of invariance. A Monte Carlo simulation study was conducted to achieve the purposes. The method consisted of generating items under a linear curve of factors model (COFM) or under the AR quasi-simplex. Composites of the items were formed at each time point and analyzed with a linear LGM or an AR quasi-simplex model. The results showed that AR quasi-simplex model yielded biased path coefficients only in the conditions with large violations of invariance. The fit of the AR quasi-simplex was not affected by violations of invariance. In general, the growth parameter estimates of the LGM were biased under violations of invariance. Further, in the presence of non-invariant loadings the rejection rates of the hypothesis of linear growth increased as the proportion of non-invariant items and as the magnitude of violations of invariance increased. A discussion of the results and limitations of the study are provided as well as general recommendations.
ContributorsOlivera-Aguilar, Margarita (Author) / Millsap, Roger E. (Thesis advisor) / Levy, Roy (Committee member) / MacKinnon, David (Committee member) / West, Stephen G. (Committee member) / Arizona State University (Publisher)
Created2013
Description
Research shows that general parenting practices (e.g., support and discipline), influence adolescent substance use. However, socialization theory suggests that parental socialization occurs not only through general parenting practices, but also through parents' attempts to influence specific behaviors and values. A growing literature supports links between substance-specific parenting and adolescent substance use. For adolescent alcohol use, there are considerable limitations and gaps within this literature. To address these limitations, the present study examined the factor structure of alcohol-specific parenting, investigated the determinants of alcohol-specific parenting, and explored its association with nondrinking adolescents' attitudes about alcohol use. Using a high-risk sample of nondrinking adolescents and their parents, the current study found three dimensions of alcohol-specific parenting using both adolescent and parent reports, but also found evidence of non-invariance across reporters. Results also revealed complex roles of parental alcohol use disorder (AUD; including recovered and current AUD), family history of AUD, and current drinking as determinants of the three dimensions of anti-alcohol parenting behaviors. Moreover, the current study showed that the effects of these determinants varied by the reporter of the parenting behavior. Finally, the current study found the dimensions of alcohol-specific parenting to be unique and significant predictors of nondrinking adolescents' attitudes about alcohol, over and above general parenting practices, parent AUD, and parent current drinking. Given its demonstrated distinctness from general parenting practices, its link with adolescent alcohol attitudes, and its potential malleability, alcohol-specific parenting may be an important complement to interventions targeting parents of adolescents.
ContributorsHandley, Elizabeth D (Author) / Chassin, Laurie (Thesis advisor) / MacKinnon, David (Committee member) / Crnic, Keith (Committee member) / Sandler, Irwin (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
Due to persistent undernutrition in India and the increased demands placed on a woman’s body during childbearing and lactation, the Indian government has implemented a program to provide supplemental nutrition packets to women in rural India. This study examines the factors influencing uptake of nutritional packets by lactating mothers in southern, rural Rajasthan. Women were recruited from 65 villages in Rajasthan, India (n=149, minimum of 2 per village) to evaluate the relationship of nutrition packet uptake and two factors--education levels and distance to the health center.
Level of education had little impact on whether or not women received the nutrition packet. Of those women with no education, 63.1% received the packet. Of those with any education, 63.9% got the packet.
In contrast, distance was strongly correlated with whether or not women received the packet. For example, of the women living within 200 meters of the health center, 93.2% received a nutrition packet. Of the women living between 250 meters and one kilometer of the health center, 68.4% received a nutrition packet. Of the women living over one kilometer from the health center, only 25% received a nutrition packet. The relationship between uptake of packets and women’s perception of distance to the health center was also explored. Out of 50 women who did not receive the packet, all of the women who said there was no health center in their village did live more than one kilometer from a health center. Of the women who lived between 250 meters and one kilometer from the health center, 40% felt it was too far. Of the women who lived more than a kilometer from the health center, 66.7% felt it was too far and 29.6% said there was no health center in their village. Again, it does not appear that ‘too far’ is just a default reason for women, but that actual distance, more so than education, is a major contributing factor in their ability to take the nutrition packet. These findings suggest that improving access to supplemental nutrition packets at the village level may increase uptake by the women.
Level of education had little impact on whether or not women received the nutrition packet. Of those women with no education, 63.1% received the packet. Of those with any education, 63.9% got the packet.
In contrast, distance was strongly correlated with whether or not women received the packet. For example, of the women living within 200 meters of the health center, 93.2% received a nutrition packet. Of the women living between 250 meters and one kilometer of the health center, 68.4% received a nutrition packet. Of the women living over one kilometer from the health center, only 25% received a nutrition packet. The relationship between uptake of packets and women’s perception of distance to the health center was also explored. Out of 50 women who did not receive the packet, all of the women who said there was no health center in their village did live more than one kilometer from a health center. Of the women who lived between 250 meters and one kilometer from the health center, 40% felt it was too far. Of the women who lived more than a kilometer from the health center, 66.7% felt it was too far and 29.6% said there was no health center in their village. Again, it does not appear that ‘too far’ is just a default reason for women, but that actual distance, more so than education, is a major contributing factor in their ability to take the nutrition packet. These findings suggest that improving access to supplemental nutrition packets at the village level may increase uptake by the women.
ContributorsJeffers, Eva Marie (Author) / Hruschka, Daniel (Thesis director) / Maupin, Jonathan (Committee member) / Cook, Jeffrey (Committee member) / Barrett, The Honors College (Contributor) / School of Human Evolution and Social Change (Contributor)
Created2015-05
Description
2015 marks the deadline for the UN Millennium Development Goal 5 to reduce global maternal mortality rate (MMR) by 75% since 1990. As of 2015, MMR has only been reduced by 45%. Many international organizations claim that more medically trained midwives can meet global maternal health care needs. This study investigates two major questions. What is the role of midwives in diverse international maternal healthcare contexts? How do midwives in these different contexts define their roles and the barriers to providing the best care for women? From May to August 2015, I conducted over 70 interviews with midwives in Netherlands, Sweden, Rwanda, Bangladesh, Australia and Guatemala, interviewing between 6 and 13 midwives from each country. The majority of midwives defined their roles as supporting women's individual capacities and power through normal birth, and knowing when to refer when high-risk complications arise. Although thematic barriers vary by country, midwives in all countries believed that maternal healthcare can be improved by increased collaboration between midwives and other health care professionals, better access to culturally appropriate services, and greater public awareness of the role of midwives.
ContributorsCarson, Anna Elizabeth (Author) / Hruschka, Daniel (Thesis director) / Maupin, Jonathan (Committee member) / School of International Letters and Cultures (Contributor) / School of Human Evolution and Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
How are perceptions of morality and disgust regarding meat consumption related to each other? Which factor is more salient in determining one's willingness to eat the meat of a specific animal? How do these answers vary across religious groups? This study investigates the ways that concepts like morality and disgust are related to food preferences and hopes to shed light on the mechanisms that enforce culturally sanctioned food taboos. The study compares 4 groups of people in the U.S.: Christians (n = 39), Hindus (n = 29), Jews (n = 23), and non-religious people (n = 63). A total of 154 participants were given surveys in which they rated their feelings about eating various animals. Data from Christian and non-religious groups exhibited similar patterns such as a high likelihood of eating a given animal when starving, while results from Jews and Hindus were consistent with their religion's respective food taboos. Despite these differences, morality and disgust are strongly correlated with one another in almost all instances. Moreover, morality and disgust are almost equally important considerations when determining willingness to eat when starving.
ContributorsParekh, Shaili Rajul (Author) / Hruschka, Daniel (Thesis director) / Jacobs, Mark (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor) / School of Human Evolution and Social Change (Contributor) / Hugh Downs School of Human Communication (Contributor)
Created2014-12
Description
The United States is experiencing an increase in the prevalence and influence of complementary and alternative medicine (CAM) in patient healthcare, reflecting the increasingly positive public and professional attitudes on the use of CAM therapies. Despite the growing presence of CAM in U.S. healthcare, there are still many barriers to integration. This study aims to reveal the attitudes of conventional, integrative and CAM practitioners concerning the major challenges of CAM's integration, explore their proposed solutions, and reveal any discrepancies in these attitudes among different types of practitioners. Twenty-eight practitioners were interviewed on the challenges in the five facets of CAM's integration: integration into hospitals, integration into medical schools, insurance coverage for CAM, licensing & regulation of CAM practitioners, and clinical research in CAM. The overall positive attitudes on the benefits of CAM's integration support previous research on the subject; however, the conventional practitioners were unable to extend these benefits to real-world application, and they were unaware of many of the challenges facing CAM's integration. The CAM practitioners attributed many of the problems facing integration to the inability of CAM's philosophy to comply with the current ideology of medical academia, health insurance model, and laws that govern the licensing and regulation of medical practitioners. The CAM and integrative practitioners perceived there to be a large resistance from conventional practitioners, specifically concerning the integration of CAM into education, providing insurance coverage for CAM, and the licensing and regulation of CAM practitioners. They attributed this to a perceived lack of research on safe and effective treatments in CAM. The conventional practitioner responses reflected this weariness of treatment effectiveness in their responses. However, the CAM and integrative practitioners believed these claims to be largely inaccurate, and constructed by the influence and manipulation of large-scale medical corporations and organizations. The participants believed that more evidence-based research in CAM, and increased public awareness in CAM therapies will force conventional practitioners to increase their knowledge in CAM, helping to alleviate their fears and skepticism of CAM therapies. By easing these concerns, dialogue can occur among practitioners of different modalities that will help to ensure a smooth integration of CAM and will raise the quality of patient healthcare by providing safe and effective resources for alternate forms of treatment.
ContributorsJohnston, Shantele Hanna Lee (Author) / Hruschka, Daniel (Thesis director) / Hurlbut, Ben (Committee member) / Barrett, The Honors College (Contributor) / School of International Letters and Cultures (Contributor) / School of Human Evolution and Social Change (Contributor)
Created2014-05
Description
Fat-stigma has become a popular topic of research in recent years as obesity and Western ideals have made their way around the globe. Previous studies have found that the internalization and expression of body norms can vary dramatically depending on location, gender, and many other cultural factors. Differing levels of body satisfaction have been linked to the internalization of these norms, and the development of low body esteem can result in many physical and emotional problems. Although there is an abundance of research on the topic of fat-stigma, few studies have investigated the related, but seemingly independent, topic of the ideal thin body. Furthermore, limited research has looked directly at body size stereotypes in Guatemala, and those that have, focused solely on Guatemala City. Furthermore, no previous cross-cultural analyses were found comparing body norms among US and rural Guatemalan adolescents. By surveying 9-10 year old students in Acatenango, Guatemala and Phoenix, Arizona, this study compared the preferences as well as stereotypes for average, thin, and fat body sizes in these two contexts. The results of this study illustrate a contrast between a fat-negative and a thin-negative culture, and highlight the complexity of the emergence of body norms around the world. We find that, in contrast to previous studies, neither the western ideal thin body nor obesity stereotypes have been internalized in Acatenango. Furthermore, negative evaluations of fat bodies and positive evaluations of thin bodies seem to be made independently of each other. Americans had a much higher prejudice against fat children and were more likely to be thin-positive (OR=1.997), while Guatemalans were more likely to be thin-negative. On average, the American students were much more polarized in their judgments on different body sizes, and experienced greater levels of body dissatisfaction. Finally, American students favored an ideal figure over one size smaller than Guatemalan students. Results suggest that there are still rural communities that have not been entirely affected by the spread of western body norms.
ContributorsCole, Dawn Michelle (Author) / Maupin, Jonathan (Thesis director) / Hruschka, Daniel (Committee member) / Barrett, The Honors College (Contributor) / School of Geographical Sciences and Urban Planning (Contributor) / School of Human Evolution and Social Change (Contributor)
Created2013-12