1925 research outputs found
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Madwomen in the arena: a female majority cohort of rural Arizona superintendents
No full textThe study’s objective was to generate a composite description of the lived experience of women serving as rural Arizona public school district superintendents with special attention to ways this experience was impacted by the time in their tenures when they comprised a majority of local superintendents. Context includes 2020 data documenting a ten-year lull in progress toward equity in the representation of women in the superintendency. Research questions sought to identify any perceived impact upon participants of working with a proximal cohort of female superintendents along with participants' access and success strategies, their perceptions of gender and equity, and the role of the setting. Transcribed interview narratives comprise the data of the phenomenological reduction within the bounds of the guiding research questions. A hermeneutic phenomenological approach informs the research methodology where findings are the themes and consensus within the response data. Arising themes were individualism and misassumption of a continued positive trajectory. Participants rejected impact of gender upon their careers, strategies, or leadership approaches. The participants mentor and contribute to the future of educational leadership but were skeptical of sponsorship. Rationale regarding under-representation focused on access barriers, including self-imposed barriers, consistent with the body of research literature. As potential remedy to inequity or stagnation, responses focused on anti-bias training for hiring governing boards and mindful action by serving superintendents. Readers may find further meaning interpreting the composite description of the experience.
Keywords: superintendent, female, underrepresentation, group, cohort, barrier
Analyzing factors affecting pedestrian crash frequency & severity considering demographic, land use, & roadway characteristics
No full textPedestrian safety is a prevalent issue across the United States, and especially in regions that experience higher pedestrian activity year-round due to warm climates, such as the state of Arizona. Recently, a steady increase in pedestrian crashes in the city of Phoenix, Arizona has occurred. To help address this issue in Phoenix and beyond, the objective of this study was to investigate factors associated with the frequency of vehicle-pedestrian crashes at the census block group level by amalgamating four datasets consisting of crash data, demographic data, land use data, and roadway characteristics. A negative binomial model and a multiple linear regression model were estimated to identify factors significantly associated with pedestrian crash frequency and crash rate, respectively. Numerous parameters in these models were found to be associated with pedestrian crashes, and the general effect (though with differing magnitudes) of most variables were similar to the few previous studies conducted in other regions, however there were important differences found that may be unique to the southwest region. Additionally, the estimation of both frequency and rate models provided unique observations as multiple variables were significant in one model and not the other, though most results were generally similar. A crash severity model was also estimated to analyze pedestrian crashes occurring within these census block groups. Ultimately, the findings of this study provide new insights that can help frame or amend policies and countermeasures aimed at improving pedestrian safety
Evaluating geophysical diversity as a surrogate for biodiversity in conservation planning
No full textIn response to the growing biodiversity crisis, governing agencies are looking to expand protected area coverage. However, it is difficult to decide which sites to protect for biodiversity because biotic information is limited and costly to obtain. Environmental diversity, particularly geophysical diversity, could be a cost-saving and effective alternative for informing site selection. In this project, I explored different variable selections to define an environmental surrogate and compared implementation methods for using the surrogate in site selection. I then evaluated surrogate performance for 42 biological inventory data sets from around the globe. From the method comparison components of this project, I found better performing procedures that I used in the final surrogate tests. Across all tests, the geophysical surrogate performed on average better than random. This project's findings suggest that spatial patterns of geophysical diversity at the landscape scale can help identify high-priority areas for maximizing species representation in conservation planning
Evaluation of a computer–based reading program
No full textThe principal of a southern Arizona elementary school, to be referred to as SMD Elementary School, had seen a drop in the standardized test scores for reading among the fourth and fifth graders, and she wanted to enable the students to improve their reading achievement. The goal of this study was to determine if New Century Reading, a computer–based reading program, could contribute to students’ improved reading achievement. This was an evaluation study and a mixed–method design using both survey and nonreactive methods. The nonreactive approach involved collecting students’ test scores from before and after they used the New Century Reading program, which were analyzed quantitatively. The population consisted of the fourth and fifth grade students within SMD Elementary School, who used the New Century Reading program, as well as the fourth and fifth grade teachers who taught those students. The instrumentation consisted of the AIMS Reading test, a Standards Based Assessment that was required by state and federal law, as well as a researcher–created survey entitled, “Teachers’ Perceptions of the New Century Reading Program” to collect qualitative data. The descriptive statistics for the multi–year reading tests showed that the average AIMS Reading test scores went up after having used the New Century Reading program. The matched–pairs t–test showed that there was no significant difference between the test score mean of the fourth–grade students before using New Century and the test score mean of the fourth–grade students after using New Century. There was, however, a significant difference between the test score means of the fifth–grade students before and after using New Century. The chi–square test of independence showed that there was an association between the performance categories during the school year 2010–2011 and school year 2011–2012. It appeared that there were some students who moved up in categories. The survey revealed that three–quarters of the teachers were not sure if the New Century Reading program helped improve the reading achievement of the students. Some three–quarters of the teachers also responded similarly to the question about which aspects of the New Century Reading program they found beneficial. Overall, they liked how the program was able to measure each student’s progress in order to individualize their ongoing lessons, which helps students learn and improve. Additionally, when asked how they would change or improve the program, three–quarters of the teachers stated that they wanted the program to be more technologically advanced, particularly with regard to graphics and animation. Some recommendations for future studies include looking at the use of the New Century Reading program with other grade levels, such as middle and high school grades, using a larger sample of teachers for the survey, studying the effectiveness of the program among a variety of ethnic groups, and evaluating the most updated version of the New Century Reading program
Pragmatic Prospection and Environmental Modifications: An Experience Sampling Study
No full textPragmatic prospection describes thinking about the future in ways that have practical utility by guiding current behavior. Recent research trends have focused on the cognitive mechanics behind prospection, but there is less research investigating the subsequent behavior involved in prospection. By adopting social cognitive theory, the current project aimed to (a) quantify the frequency of everyday pragmatic prospection in a sample of college students, (b) investigate relationships between prospection and environmental modifications, and (c) investigate the role reinforcement sensitivity bias has on pragmatic prospection. Using experience sampling methodology, participants answered an 8-question survey asking about participants most recent thought and intended behavior sent to them via text message on their personal phones 30 times throughout a course of five days. Results indicated that after thoughts about the present, thoughts about the future were the most common. Prospection made up about 75% of all future thoughts. Results indicated that deliberately thinking and external cues were the main source of prospection (what participants thought caused the thought to happen). The current project identified three different types of environments people modify: personal, social, and physical environments. Prospection was significantly related to more environmental modifications and more related subsequent behavior than other kind of thoughts. Thoughts about the future were the most meaningful compared to thoughts with other temporal contexts. Finally, within thoughts about prospection, people who tend to avoid unpleasant outcomes were positively related to avoidance behavior and negatively related to approach behavior. Adopting the pragmatic theory of prospection (Baumeister et al., 2016) and social cognitive theory (Bandura, 2001) I demonstrate that people have a natural tendency to engage in future thinking that serves practical utility by guiding current behavior. Just like the environment has implications on engaging in prospection (external cues), prospection leads to behaviors that involve modifications to the environment
Reclaiming the Mountains: A Lefebvrian analysis of national park space during a federal shutdown
Get PDFNational park space is intrinsically tied to the stability of the nations in which it is established. In December 2018, the federal government of the United States began a
35-day partial shutdown, destaffing national parks across the country in a de facto
governance lapse. This study uses a political ecological analysis to examine how
instability in the federal government allowed space to be reappropriated by different
environmental agents in Great Smoky Mountains National Park during the 2018-2019
partial shutdown. Interviews with park staff, community members, adjacent
governmental institutions and non-profits were conducted and revealed a novel set of
relationships between human and non-human actors and how governance failures
contributed to the production of new social and physical landscapes. As federal
authority waned during the 35 days that the park was left open but unattended,
volunteer stewardship of some areas of the park was undertaken by local communities
and non-profits while wildlife freed from human oversight remade the landscape to meet
its own needs. Moreover, a pervasive normative reality led the park to be reinterpreted
in a manner inconsistent with its status as a federal monument and historical
inequalities were reproduced in the communities surrounding the park. This study
ultimately situates the shutdown in Great Smoky Mountains National Park within a wider
historical context to examine how destabilizing governance failures at the highest levels of the United States government intersect with the material history of the park, revealing
novel social interactions and new reproductions of old disparities
Climate effects on canopy arthropod communities of pinyon pine and juniper trees
No full textPinyon-juniper woodlands have undergone compositional changes because of climate change in the last several decades as pinyons have succumbed to droughts and bark beetles, and juniper have encroached into grass and shrublands. These changes pose challenges to animal communities utilizing these woodlands, especially for species that specialize on pinyon pine or plant species sensitive to changes in climate. Here we assess potential differences in foliar and bark arthropod communities between pinyon pine (Pinus edulis) and one-seed juniper (Juniperus monosperma) along three elevational gradients in northern Arizona. We sampled 3,275 arthropods comprising 117 species over two years. Some foliar and bark arthropods species differ in abundance and occurrence on or juniper trees, and it is likely that these species specialize on one of these tree species or utilize a resource only associated with one of these tree species. Climatic factors strongly affected arthropods communities and appeared to drive differences between sites and across elevations.Overall, our results suggest that most tree arthropods are not entirely dependent on one of these tree species in pinyon-juniper woodlands, but are strongly linked to climate, especially precipitation. Our results show that tree arthropods in this habitat are more susceptible to changes in climate, especially at lower elevations where it is hot and dry, than changes in dominant tree vegetation. We discuss ecological and management implications of our findings and compare them to foliar and bark arthropods relationships with vegetation in other systems
Investigating the role of titin in skeletal muscles from mdm mice with a deletion in N2A titin
No full textMuscle physiology is usually considered as a well-developed field which is sufficiently defined by fundamental principles from the sliding filament and swinging cross-bridge theories. However, a key muscle protein, titin, was isolated 20 years after establishment of these original theories. Even after two decades, the role of titin in active muscle function remains elusive. Titin spans from Z-line to M-line, comprising a half-sarcomere. Most previous studies focused on the I-band, where titin is elastic and serves as an attachment point between thick and thin filaments. Previous studies proposed that the compliance of titin precludes a role in active muscle contraction. However, recent studies have proposed that titin stiffness increases in skeletal muscles during active contraction. To explore the role of titin in skeletal muscles, we used mdm mice that have deletion in N2A titin, which has been proposed to bind to actin in active muscles. The main aim of this dissertation was to investigate the role of titin in mdm mice, specifically how the small deletion in the N2A region affects residual force enhancement (RFE), passive stress, and sarcomere structure during activation and stretch. Our results demonstrate that the mdm mutation decreases RFE and leads to an alternate splicing pattern in the PEVK region of mdm mice which ultimately results in higher passive stress in mdm skeletal muscles. The x-ray diffraction results suggest that I1,0 intensity, lattice spacing and thick filament periodicity are activation- and length-dependent properties of WT muscles which are absent in mdm muscles. The results of all three studies are consistent with lower the active stiffness of mdm muscles (Powers et al., 2016; Monroy et al., 2017), possibly due to lack of N2A titin-actin binding in active muscle (Dutta et al., 2018). Our research was focused on gaining a deeper insight into the function of titin in skeletal muscles from mdm mice with a small deletion in N2A titin. Results from these studies can help us to better understand the mechanisms contributing to muscle weakness in titin-related skeletal muscle diseases
Assessing the association of ten-year cardiovascular disease risk with depression in the national health and nutrition examination surveys
Get PDFMajor depressive disorder and cardiovascular diseases (CVD) are two of the leading causes of disability worldwide and CVD is the leading cause of death in the US. There is strong evidence that depression is associated with increased risk of initial CVD events and thus it is important to quantify CVD risk by depression status in persons free of clinical CVD. Extant literature characterizing this association is limited by heterogeneous and suboptimal assessments of both depression and CVD risk, hindering prevention and treatment. In particular, almost no studies to date have examined the depression/CVD risk association using contemporary, ecologically valid depression and CVD risk assessments. The objective of this study was to evaluate the association between depression, measured by the Patient Health Questionnaire-9 (PHQ-9), with CVD risk, as measured by the pooled cohort equations, in a national sample of U.S. adults. In sex-specific analyses, depression was consistently associated with higher 10-year ASCVD risk for women, with observed ten-year risk 1-3% higher for depressed women. However, depression was associated with higher ASCVD risk for men 40-49 years of age but not associated with ASCVD risk in older groups. These findings may be useful for identifying comorbid CVD risk when screening for depression and determining appropriate risk reduction strategies for depressed persons, particularly women, who are at elevated medium-term risk for clinical CVD.Keywords: depression, ASCVD risk, PHQ-9, risk factors, cardiovascular disease, assessmen
Environment specific alleles related to adaptive seasonal traits and the fitness consequences of phenology for Pinus strobiformis
Get PDFRapid shifts in temperature and precipitation related to anthropogenic climate change threaten to decouple evolved responses to environmental stimuli resulting in maladaptive phenology. Asynchronous phenology could result in increased mortality in forest trees and trigger a cascade of impacts on large scale ecosystem processes. Understanding phenological responses to novel conditions and identifying the genetic architecture of phenological traits and survival can aid forest managers in identifying both vulnerable populations and populations with substantial genetic variation. Pinus strobiformis is a high elevation conifer whose disjunct and isolated distribution across the American southwest makes it particularly vulnerable to climate change. P. strobiformis contributes to biodiversity in mixed conifer forests, but species distribution models predict that suitable habitat for P. strobiformis will decrease across their current range and shift to higher latitudes and altitudes. Recent genetic analysis described the extent of a hybrid zone in New Mexico and Arizona between P. strobiformis and the more northerly distributed Pinus flexilis. These hybrid populations may possess unique allele combinations necessary for survival under combined water limitations and freezing conditions. This thesis builds upon a rapidly growing body of knowledge through an international collaborative effort across multiple universities and government agencies to understand the physiology, ecology, genetics, and resistance to invasive pathogens. In the first chapter we utilized three common gardens at Pinus strobiformis climate margins to detect genetic markers related to phenology, survival, and bud damage through both single and multi-trait genome wide association analyses. Multi-trait groupings included 1) the same trait measured at multiple time points, or longitudinal measures, of the same trait across multiple time periods, 2) different components of spring phenology bud development, and 3) traits that had significant associations with maternal seed source climate. We detected 103 SNPs related to survival, phenology, and bud damage over the span of two years. Most minor, or less common, alleles detected for traits had a negative effect on survival and variable effects on spring phenology. Using multi-trait groupings improved our ability to detect loci and identify shared genetic influences among multiple traits. Our results suggest that phenology, survival, and bud damage in Pinus strobiformis are regulated by complex genetic and environment interactions, environment specific allele sensitivities, and indirect effects of loci on multiple phenotypes.
The second chapter extends the utility of the genome-wide association analyses by investigating phenological relationships with survival and the distribution of minor alleles along climate gradients. We investigated variation across years and growing conditions in phenological traits and their relationship with survival. The relationships among phenological traits and survival were used to group alleles by their garden specific effects. Alleles that increased survival under particular growing conditions at a specific time were considered favorable, whereas alleles that decreased survival were considered unfavorable. These allele distinctions are garden specific and likely do not represent alleles that are unfavorable nor favorable for Pinus strobiformis in their home range. An additional group of alleles was created for alleles that were related to spring phenological development. These groups were used to investigate the relationships among allele counts for individual maternal trees and maternal seed source climate variables and garden specific survival. Spring phenology and bud damage varied across the two study years and across gardens. Fall phenology demonstrated little variation between the high and low elevation gardens. Maternal trees with greater bud damage had lower survival at all gardens, whereas spring bud burst phenology had opposing relationships with survival at the two extreme gardens. Our results demonstrate that early growth in P. strobiformis responds to climatic shifts in context dependent ways. Maternal P. strobiformis trees with more unfavorable minor alleles and more phenology related minor alleles had lower survival. P. strobiformis families with more favorable, unfavorable or phenology related minor alleles were from seed source sites with less winter precipitation and more climate moisture deficit. This pattern suggests that Pinus strobiformis may have retained low frequency, rare alleles, through a combination of selective pressure on early season growth, stressful conditions, and seasonal moisture. Additionally, local adaptation within large highly variable maternal populations; and unequal patterns of gene flow may have contributed to the retention of these alleles. Our study contributes to the developing body of work that highlights the importance of seasonal precipitation and moisture deficit for P. strobiformis local adaptation and evolutionary history