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- Creators: Arizona State University
Description
The repression of reproductive competition and the enforcement of altruism are key components to the success of animal societies. Eusocial insects are defined by having a reproductive division of labor, in which reproduction is relegated to one or few individuals while the rest of the group members maintain the colony and help raise offspring. However, workers have retained the ability to reproduce in most insect societies. In the social Hymenoptera, due to haplodiploidy, workers can lay unfertilized male destined eggs without mating. Potential conflict between workers and queens can arise over male production, and policing behaviors performed by nestmate workers and queens are a means of repressing worker reproduction. This work describes the means and results of the regulation of worker reproduction in the ant species Aphaenogaster cockerelli. Through manipulative laboratory studies on mature colonies, the lack of egg policing and the presence of physical policing by both workers and queens of this species are described. Through chemical analysis and artificial chemical treatments, the role of cuticular hydrocarbons as indicators of fertility status and the informational basis of policing in this species is demonstrated. An additional queen-specific chemical signal in the Dufour's gland is discovered to be used to direct nestmate aggression towards reproductive competitors. Finally, the level of actual worker-derived males in field colonies is measured. Together, these studies demonstrate the effectiveness of policing behaviors on the suppression of worker reproduction in a social insect species, and provide an example of how punishment and the threat of punishment is a powerful force in maintaining cooperative societies.
ContributorsSmith, Adrian A. (Author) / Liebig, Juergen (Thesis advisor) / Hoelldobler, Bert (Thesis advisor) / Gadau, Juergen (Committee member) / Johnson, Robert A. (Committee member) / Pratt, Stephen (Committee member) / Arizona State University (Publisher)
Created2011
Description
Higher education institutions in the state of Arizona have experienced a reduction in government funding due to the economic challenges the state is facing combined with an ongoing national recession. Three higher education institutions studied are located in Phoenix, Arizona. The three higher education institutions are Phoenix College, Arizona State University and The University of Phoenix. An analysis of documents made public by each institution was conducted and high level administrators at each institution were interviewed to learn about revenue streams currently active and planned. The results of this set of analyses were presented to the leadership team of Phoenix College in a three-hour strategic planning and priority setting meeting. The action research study assisted Phoenix College administrators in gaining knowledge about and initiating action plans to increase revenue through entrepreneurial strategies. Increased funding is necessary to offset reductions in state aid and property tax revenues. Implementing entrepreneurial strategies to increase funding can promote self-reliance and flexibility and can mitigate the damage to institutional mission success that is threatened by reductions in traditional funding. The strategic planning and priority setting exercise conducted at Phoenix College produced three immediate outcomes: it informed the community of practice about entrepreneurial strategies to increase funding that are in use by higher education institutions located in greater Phoenix, Arizona; it influenced the community of practice to examine entrepreneurial revenue streams and; it committed the leadership team to pursuing and enlarging three additional revenue streams.
ContributorsKakar, Casandra Gwen (Author) / Clark, Christopher M. (Thesis advisor) / De Los Santos Jr., Alfredo G. (Committee member) / Giovannini, Eugene (Committee member) / Arizona State University (Publisher)
Created2011
Description
The purpose of this study was to help increase success for first-generation Latina students at Arizona State University by providing a group mentoring support experience during the spring semester of their sophomore year. Thirteen first-generation Latinas in their sophomore year were recruited from the Obama Scholars Program at Arizona State University. These students participated in one or two 90-minute group mentoring intervention sessions during the spring semester of their sophomore year and responded to reflection questions at the end of each session. Additional data were collected through e-journaling and field notes to document the mentoring process and the short-term effects of the group mentoring intervention. Study participants named three themes as critical to their college success: college capital, confidence, and connections. Participants also reported that the intervention of group mentoring sessions helped them increase their knowledge of available resources, feel more confident about their remaining years in college, make connections with other first-generation Latinas, and convinced them to recommit themselves to working hard for immediate academic success to achieve their goal of becoming the first in their families to become a college graduate.
ContributorsGolden, Amy Edith (Author) / Clark, Christopher M. (Thesis advisor) / Wilkinson, Christine Kajikawa (Committee member) / Duplissis, Mark (Committee member) / Arizona State University (Publisher)
Created2011
Description
The structural design of pavements in both highways and airfields becomes complex when one considers environmental effects and ground water table variation. Environmental effects have been incorporated on the new Mechanistic-Empirical Pavement Design Guide (MEPDG) but little has been done to incorporate environmental effects on airfield design. This work presents a developed code produced from this research study called ZAPRAM, which is a mechanistically based pavement model based upon Limiting Strain Criteria in airfield HMA pavement design procedures. ZAPRAM is capable of pavement and airfield design analyses considering environmental effects. The program has been coded in Visual Basic and implemented in an event-driven, user-friendly educational computer program, which runs in Excel environment. Several studies were conducted in order to insure the validity of the analysis as well as the efficiency of the software. The first study yielded the minimum threshold number of computational points the user should use at a specific depth within the pavement system. The second study was completed to verify the correction factor for the Odemark's transformed thickness equation. Default correction factors were included in the code base on a large comparative study between Odemark's and MLET. A third study was conducted to provide a comparison of flexible airfield pavement design thicknesses derived from three widely accepted design procedures used in practice today: the Asphalt Institute, Shell Oil, and the revised Corps of Engineering rutting failure criteria to calculate the thickness requirements necessary for a range of design input variables. The results of the comparative study showed that there is a significant difference between the pavement thicknesses obtained from the three design procedures, with the greatest deviation found between the Shell Oil approach and the other two criteria. Finally, a comprehensive sensitivity study of environmental site factors and the groundwater table depth upon flexible airfield pavement design and performance was completed. The study used the newly revised USACE failure criteria for subgrade shear deformation. The methodology utilized the same analytical methodology to achieve real time environmental effects upon unbound layer modulus, as that used in the new AASHTO MEPDG. The results of this effort showed, for the first time, the quantitative impact of the significant effects of the climatic conditions at the design site, coupled with the importance of the depth of the groundwater table, on the predicted design thicknesses. Significant cost savings appear to be quite reasonable by utilizing principles of unsaturated soil mechanics into the new airfield pavement design procedure found in program ZAPRAM.
ContributorsSalim, Ramadan A (Author) / Zapata, Claudia (Thesis advisor) / Witczak, Matthew (Thesis advisor) / Kaloush, Kamil (Committee member) / Arizona State University (Publisher)
Created2011
Description
To sustain world preeminence, 21st century university and college leaders in the United States are redesigning their institutions organizationally and culturally to align with the direction of local and global societies and markets. The New American University enterprise model at Arizona State University has become one of the leading organization and cultural redesigns in United States higher education since its inception in 2002. Yet, sustaining a 21st century model such as this one means every individual in the college or university must understand his or her specific role to further progress the new model forward. Therefore, to advance and sustain a 21st century higher education redesign model at a U.S. college or university, it becomes imperative that every master-level professional who works in the academic/student services field at the institution understand his or her specific role in helping to further progress the new model forward. To this end, there is a need to change the way graduate students in higher education/student affairs masters programs are educated to work in the 21st century institution. This change can prepare new professionals to understand these enterprise models and how to integrate them into their practice in order to meet the needs of the institution, local and global societies and markets. The purpose of this action research study is to highlight one program, the ASU M.Ed. Higher and Postsecondary program, and show how graduates from 2007 - 2011 understand New American University concepts and integrate them into professional practice within higher education. Through use of a quantitative approach, this action research study described how the ASU M.Ed. in Higher and Postsecondary program graduate students' understanding of New American University concepts informs their thinking and practice to lead and respond to changes and challenges facing today's 21st century higher education field.
ContributorsAntonucci, Mark J (Author) / Ewing, Kris M (Thesis advisor) / Denke, Mark (Committee member) / Rund, James (Committee member) / Arizona State University (Publisher)
Created2011
Description
Although U.S. rates of college enrollment among 18-24 year olds have reached historic highs, rates of degree completion have not kept pace. This is especially evident at community colleges, where a disproportionate number of students from groups who, historically, have had low college-completion rates enroll. One way community colleges are attempting to address low completion rates is by implementing institutional interventions intended to increase opportunities for student engagement at their colleges. Utilizing logistic and linear regression analyses, this study focused on community college students, examining the association between participation in institutional support activities and student outcomes, while controlling for specific student characteristics known to impact student success in college. The sample included 746 first-time, full-time, degree-seeking students at a single community college located in the U.S. Southwest. Additional analyses were conducted for the 440 first-time, full-time, degree-seeking students in this sample who placed into at least one developmental education course. Findings indicate that significant associations exist between different types of participation in institutional interventions and various student outcomes: Academic advising was found to be related to increased rates of Fall to Spring and Fall to Fall persistence and, for developmental education students, participation in a student success course was found to be related to an increase in the proportion of course credit hours earned. The results of this study provide evidence that student participation in institutional-level support may relate to increased rates of college persistence and credit hour completion; however, additional inquiry is warranted to inform specific policy and program decision-making at the college and to determine if these findings are generalizable to populations outside of this college setting.
ContributorsBeckert, Kimberly Marrone (Author) / De Los Santos Jr., Alfredo G (Thesis advisor) / Thompson, Marilyn S (Thesis advisor) / Berliner, David C. (Committee member) / Arizona State University (Publisher)
Created2011
Description
Barrett, The Honors College at Arizona State University (ASU) serves as a universal role model for organizing the resources of an institution to support highly motivated and prepared students. In 2009, Barrett, The Honors College (Barrett) opened the nation's first purposefully designed undergraduate honors residential college campus. Given the current demand by other American higher education institutions who wish to better understand how Barrett emerged as a distinct and singular model for an honors residential college experience, this action research study explores the effectiveness of the decisions, execution and outcomes central to Barrett's development. Five senior administrators of college units or universities were interviewed and provided insight for constructing a design for how other honors programs and colleges can learn from the challenges and accomplishments presented in developing an honors college for the 21st century while replicating Barrett's success. The study is framed in the overall context of how Barrett actualizes the New American University at ASU in meeting the demand for producing students that can compete in a global marketplace.
ContributorsHermann, Kristen (Author) / Ewing, Kris M (Thesis advisor) / Rund, James (Committee member) / Hesse, Marian (Committee member) / Arizona State University (Publisher)
Created2011
Description
The advent of advanced reproductive technologies has sparked a number of ethical concerns regarding the practices of reproductive tourism and commercial gestational surrogacy. In the past few decades, reproductive tourism has become a global industry in which individuals or couples travel, usually across borders, to gain access to reproductive services. This marketable field has expanded commercial gestational surrogacy--defined by a contractual relationship between an intending couple and gestational surrogate in which the surrogate has no genetic tie to fetus--to take on transnational complexities. India has experienced extreme growth due to a preferable combination of western educated doctors and extremely low medical costs. However, a slew of ethical issues have been brought to the forefront: the big ones manifesting as concern for reduction of a woman's worth to her reproductive capabilities along with concern for exploitation of third world women. This project will be based exclusively on literature review and serves primarily as a call for cultural competency and understanding the circumstances that gestational surrogates are faced with before implementing policy regulating commercial gestational surrogacy. The paper argues that issues of exploitation and commodification hinge on constructions of motherhood. It is critical to define and understand definitions of motherhood and how these definitions affect a woman's approach to reproduction within the cultural context of a gestational surrogate. This paper follows the case study of the Akanksha Infertility Clinic in northern India, a surrogacy clinic housing around 50 Indian surrogates. The findings of the project invokes the critical significance of narrative ethics, which help Indian surrogates construct the practice of surrogacy so that it fits into cultural comprehensions of Indian motherhood--in which motherhood is selfless, significant, and shared.
ContributorsMoorthy, Anjali (Author) / Robert, Jason S (Thesis advisor) / Hurlbut, Benjamin (Committee member) / Ellison, Karin (Committee member) / Arizona State University (Publisher)
Created2011
Description
Studies have demonstrated that anthocyanins can function as antioxidants, reduce inflammation, and improve dyslipidemia. Tart cherries are anthocyanin-rich, making them particularly attractive as a functional food to improve cardiovascular disease (CVD) risk. There have been few published studies to date examining the impact of tart cherries on biomarkers of dyslipidemia and inflammation, particularly in overweight and obese individuals at high risk for these conditions. This study evaluated the effect of consuming 100% tart cherry juice daily on blood lipids including total cholesterol, low-density lipoprotein cholesterol (LDL-C), calculated very low density lipoprotein cholesterol (VLDL-C), triglycerides (TG), high density lipoprotein cholesterol (HDL-C), and the CVD risk ratios, as well as the inflammatory biomarkers interleukin 6 (IL-6), interleukin 10 (IL-10), tumor necrosis factor-alpha (TNF-alpha), C-reactive protein (CRP), monocyte chemotactic protein-1 (MCP-1), and erythrocyte sedimentation rate (ESR) following a 4-week period. Based on the high anthocyanin content of tart cherries, it was hypothesized that the lipid and inflammatory profiles would be significantly improved following the intervention. A total of 26 men and women completed this 4-week randomized, single-blind, placebo-controlled, crossover study. Participants were randomized to drink either 8 ounces of placebo beverage or tart cherry juice daily for 4 weeks. Following a 4-week washout period, the alternate beverage was consumed. Ultimately, this investigation demonstrated no statistically significant alterations in any of the lipid or inflammatory biomarkers when analyzed across time and between interventions (p > 0.05). As expected, glucose and insulin parameters remained stable over the duration of the study, as well as self-reported physical activity level, total calorie consumption, and macronutrient intake. However, trans-fat was reported to be significantly higher during the cherry arm of the study as compared to the placebo arm (p < 0.05), potentially confounding other results. Although the results of this study were equivocal, it is feasible that a higher dose, longer treatment duration, or more susceptible target population may be required to elicit significant effects. Consequently, further investigation is necessary to clarify this research.
ContributorsColes, Katie (Author) / Martin, Keith R. (Thesis advisor) / Traustadottir, Tinna (Committee member) / Vega-Lopez, Sonia (Committee member) / Arizona State University (Publisher)
Created2012
Description
This dissertation describes development of a procedure for obtaining high quality, optical grade sand coupons from frozen sand specimens of Ottawa 20/30 sand for image processing and analysis to quantify soil structure along with a methodology for quantifying the microstructure from the images. A technique for thawing and stabilizing frozen core samples was developed using optical grade Buehler® Epo-Tek® epoxy resin, a modified triaxial cell, a vacuum/reservoir chamber, a desiccator, and a moisture gauge. The uniform epoxy resin impregnation required proper drying of the soil specimen, application of appropriate confining pressure and vacuum levels, and epoxy mixing, de-airing and curing. The resulting stabilized sand specimen was sectioned into 10 mm thick coupons that were planed, ground, and polished with progressively finer diamond abrasive grit levels using the modified Allied HTP Inc. polishing method so that the soil structure could be accurately quantified using images obtained with the use of an optical microscopy technique. Illumination via Bright Field Microscopy was used to capture the images for subsequent image processing and sand microstructure analysis. The quality of resulting images and the validity of the subsequent image morphology analysis hinged largely on employment of a polishing and grinding technique that resulted in a flat, scratch free, reflective coupon surface characterized by minimal microstructure relief and good contrast between the sand particles and the surrounding epoxy resin. Subsequent image processing involved conversion of the color images first to gray scale images and then to binary images with the use of contrast and image adjustments, removal of noise and image artifacts, image filtering, and image segmentation. Mathematical morphology algorithms were used on the resulting binary images to further enhance image quality. The binary images were then used to calculate soil structure parameters that included particle roundness and sphericity, particle orientation variability represented by rose diagrams, statistics on the local void ratio variability as a function of the sample size, and the local void ratio distribution histograms using Oda's method and Voronoi tessellation method, including the skewness, kurtosis, and entropy of a gamma cumulative probability distribution fit to the local void ratio distribution.
ContributorsCzupak, Zbigniew David (Author) / Kavazanjian, Edward (Thesis advisor) / Zapata, Claudia (Committee member) / Houston, Sandra (Committee member) / Arizona State University (Publisher)
Created2011