Search Results (1 - 25 of 72 Results)

Sort By  
Sort Dir
 
Results per page  

Hayes Nelson, Geraldine L.A STUDY OF SINGLE MOTHERS' EXPERIENCE OF PERSISTENCE AT A FOUR-YEAR PUBLIC INSTITUTION
PHD, Kent State University, 2009, College of Education, Health, and Human Services / Department of Teaching, Leadership and Curriculum Studies

The overall purpose of this study was to uncover and describe the barriers that low-income, single mothers between the ages of 17-24 experience and the strategies they adopt in their efforts to persist through year one to year three of college at a four-year public university. Adult education scholarship has shed light on the obstacles to college enrollment and persistence for adult students. For example, Cross (1981) classified obstacles that have an impact on the persistence and retention of adult students under three categories: situational, institutional, and dispositional. Non-traditional age adult students are challenged by these barriers as they attempt to enroll and persist in college. Less well known is whether these barriers also pertain directly to single mothers who are traditional age students with adult responsibilities.

This study provided an examination of traditional age, first generation, low-income single mothers’ persistence in college from entry to third year at a four-year public institution. In addition, the study examined multiple barriers and strategies concerning student’s employment and residential status, relationships of students with parents, and academic/college preparedness. The qualitative inquiry method used in this study allowed for an examination of low-income first generation student and their persistence from year to year. Narrative analysis was utilized in this study to assist the researcher in creating a written detail of the phenomena of single parents’ persistence towards college completion and to investigate and identify barriers and support systems identified by single-parent students The researcher employed a retelling of the struggles and strategies of the study participants as individual interviews were weaved together in the coding and discussion of the study.

Committee:

Steve O. Michael, PhD (Committee Chair); Gary M. Padak, PhD (Committee Member); Dale L. Cook, PhD (Committee Member)

Subjects:

Education

Keywords:

young mother's; college persistence; college experience; teen parent; minority college persistence; under-represented in college; persistence

Du, DongContributions to Persistence Theory
Doctor of Philosophy, The Ohio State University, 2012, Mathematics

Persistence theory discussed in this thesis is an application of algebraic topology (Morse Theory) to Data Analysis, precisely to qualitative description of point cloud data. Mathematically a point cloud data is a finite metric space of a very large cardinality. It can be geometrized as a filtration of simplicial complexes and the homology changes of these complexes provide qualitative information about the data. There are new invariants which permit to describe the changes in homology and these invariants are the “bar codes”.

In Chapter 3 work is done to develop additional methods for the calculation of bar codes and their refinements. When the coefficient field is Z_2, the calculation of bar codes is done by ELZ algorithm (named after H. Edelsbrunner, D. Letscher, and A. Zomorodian). When the coefficient field is R, we developed an algorithm based on the Hodge decomposition.

The original persistence theory can be viewed as a sort of Morse Theory and involves the “sub level sets” of a nice map. With Dan Burghelea and Tamal Dey we developed a persistence theory about level sets in Chapter 4. This is a refinement of the original persistence. The level persistence is an alternative to Zigzag persistence considered by G. Carlsson and V. D. Silva. I discuss new computable invariants and how they are related to the known ones. These invariants are referred to as “relevant level persistence numbers” and “positive and negative bar codes”. We provide enhancements and modifications of ELZ algorithm to calculate such invariants and illustrate them by examples.

Chapters 3 and Chapter 4 are preceded by background materials (Chapter 2) where the concepts of algebraic topology used in this paper are defined.

Committee:

Dan Burghelea (Advisor); Zig Fiedorowicz (Committee Member); Yusu Wang (Committee Member); Alan Saalfeld (Committee Member)

Subjects:

Mathematics

Keywords:

PCD; Vietoris-Rips Complex; Persistent Homology; Bar Codes; Level Persistence; Sub Level Persistence; Hodge Decomposition; Polytopal Complex; Simplicial Complex

Ketron, Shannon M.An Examination of Career Persistence Among Special Education Teachers in Cross-Categorical Settings
EdD, University of Cincinnati, 2007, Education : Urban Educational Leadership
This qualitative study examined attrition and retention in special education teachers in cross-categorical settings. Specifically, this project investigated the reasons why these teachers remain in the field. In order to gather relevant data, the researcher interviewed ten teachers who consecutively taught in this field for a period of five to twenty years. The researcher conducted interviews with the participants in order to understand what factors influence teacher retention. The goal was to discover common patterns, themes, and other factors that determine longevity. The research revealed that special education teachers are more likely to remain in the field if they are able to concretely identify with students; in addition, teachers who can make both personal and professional changes that benefit students persist. The research also showed that in order for teachers to thrive in cross-categorical settings, they must clearly identify their career goals and objectives. Specifically, in consideration of the input from the ten participants, this study identified seventeen factors that influence teacher retention. Finally, this study compared those seventeen factors to the existing literature on special education teacher retention to establish a conceptual framework. This framework highlights career choices, along with factors that influence teacher retention in special education cross-categorical classrooms.

Committee:

Dr. Lanthan Camblin (Advisor)

Keywords:

Career Persistence Among Special Education Teachers; Career Persistence Among Teachers; Teacher Retention; Cross-Categorical Settings

Littman, Eric MarshallProspective Control: Effect of Exploratory-task-generated-motion on Adaptation in Real and Virtual Environments
Master of Arts, Miami University, 2009, Psychology
Prospective control can be characterized as the ability to anticipate future events and act in an anticipatory manner to arrive at a desired goal. If this process is disturbed, one must actively explore the environment to properly detect new mappings. Virtual environments are able to circumvent the limitations of the physical environment and therefore can aid in determining the boundaries of people’s ability to engage in prospective control. However, it has not been shown that the behaviors exhibited in these contexts are generalizable. Participants’ head motion was recorded while they navigated through a physical or virtual maze. The results indicated main effects of time and segment as well as a time x segment interaction for both yaw and pitch rotations. There was no significant difference between the physical and virtual conditions nor were there any significant interactions involving condition. These changes reflect how behavior is modified to regain prospectivity.

Committee:

L. James Smart, PhD (Advisor); Robin D. Thomas, PhD (Committee Member); David A. Waller, PhD (Committee Member)

Subjects:

Psychology; Technology

Keywords:

Prospective Control; Adaptation; Virtual Environments; Virtual Reality; Perception; Action; Distortion; Navigation; Motor Control; Motion; Posture; Postural Sway; Hurst Exponent; Persistence; Anti-Persistence; Goal-Directed Behavior; Behavior

Rauf, AbdulPERSISTENCE, DISTRIBUTION AND IMMUNOPATHOGENESIS OF INFECTIOUS BURSAL DISEASE VIRUS IN CHICKENS
Doctor of Philosophy, The Ohio State University, 2011, Veterinary Preventive Medicine
The goal of study was to understand the persistence distribution and immunopathogensis of infectious bursal disease virus in chickens. A series of experiments were designed to determine the persistence, distribution and quantification of IBDV strains in lymphoid and non-lymphoid tissues of specific pathogen free (SPF) chickens and commercial broiler chickens. Five separate experiments were conducted using 2 and 4 weeks old SPF chickens and 2 weeks old commercial broilers having maternally derived antibodies. The virus strains were detected the longest in bursal tissues followed by spleen, thymus and bone marrow. In non-lymphoid tissues, both of the strains were detected for the longest period in the caecum followed by liver, kidney, pancreas, lungs, thigh muscles and breast muscles. Although the virus can persist in the bursa of SPF chickens for 4 weeks, it is very unlikely that the infectious virus will be present in the processed meat. In addition, the RT-PCR results are not sufficient to indicate the presence of the infectious virus. A study was conducted to better understand the innate and adaptive immune responses in chickens against IBDV. Three-week-old specific pathogen free chickens were inoculated intraocularly with standard challenge strain (STC) (cIBDV) and a variant strain Indiana (IN) (vIBDV). The cIBDV produced more pronounced bursal damage and inflammatory response as compared to vIBDV. There were significant differences in the expression of innate (IFN-α and IFN-β), proinflammatory cytokine and mediator (IL-6 and iNOS) in cIBDV- and vIBDV-infected bursas. The expression of chemokines genes, IL-8 and MIP-α was also higher in cIBDV-infected chickens during the early phase of infection. The expression of Toll like receptor 3 (TLR3) was downregulated at PIDs 3, 5, and 7 in the bursas of vIBDV-infected chickens whereas TLR3 was upregulated at PIDs 3 and 5 in cIBDV-infected bursas. In vIBDV-infected bursa, TLR7 expression was downregulated at PIDs 3 and 5 and upregulated at PID 7.These findings will be useful in understanding the differential immuno-pathogenesis of classical and variant strains of IBDV. In the last part we studied the adaptive immune responses of IBDV in chickens. In this study, we evaluated the molecular mechanisms of cytotoxic T cell responses in the pathogenesis of IBDV in chickens. Infection of chickens with IBDV was accompanied by the infiltration of CD4+ and CD8+ T cells in the bursa. There was an upregulation in the gene expression of important cytolytic molecules; perforin (PFN), granzyme-A (Gzm-A), DNA repair and apoptotic proteins; high mobility proteins group (HMG) and poly (ADP-ribose) polymerase (PARP) in the bursa of Fabricius (BF), whereas expression of NK (natural killer) lysin was downregulated. Importantly, PFN producing CD4+ and CD8+ T cells were also detected in the bursa of IBDV-infected chickens by immunohistochemistry. The findings of this study highlight the mechanisms of IBD pathogenesis and the role of cytotoxic T cells in the clearance of virus-infected cells.

Committee:

Yehia Saif, Dr. (Advisor); Daral Jackwood, Dr. (Committee Member); Chang Won Lee, Dr. (Committee Member); Gireesh Rajashekara, Dr. (Committee Member); Renukaradhya Gourapura, Dr. (Committee Member)

Subjects:

Virology

Keywords:

IBDV; Innate and adaptive immune response; persistence and distribution

Pradhan, SiddharthQuantification of Graphene Oxide Structure Using an Improved Model
MS, University of Cincinnati, 2012, Engineering and Applied Science: Materials Science
Graphite Oxide was prepared via oxidation in two stages in strong oxidizing conditions. Graphene oxide was made by suspending graphite oxide in water and N-Methyl-2-Pyrrolidone (NMP). The structure of suspension is characterized using small-angle x-ray scattering. 1% and 2% graphene oxide in water, 1% graphene oxide in NMP has been analyzed. Fractal dimension of crumpled sheet and other dimensions have been reported for 1% and 2% graphene oxide in this thesis. A new model for graphite oxide structure has been reported here. 2D persistence sheets have been introduced for the first time. Other characterization techniques have been used to verify crumpling and oxidation of graphite.

Committee:

Gregory Beaucage, PhD (Committee Chair); Jude Iroh, PhD (Committee Member); Vikram Kuppa, PhD (Committee Member)

Subjects:

Physics

Keywords:

Graphene oxide;Graphite oxide;persistence sheet;crumpling;fractal dimension;new model;

Buse, Kathleen RelihanWomen Persisting in the Engineering Profession: A Paradoxical Explanation Adapting Intentional Change Theory
Doctor of Philosophy, Case Western Reserve University, 2012, Management

Women remain underrepresented in the engineering profession comprising only 10% of the employed engineers in 2010 while in that same year women exceeded more than half of those employed in professional, managerial and related occupations according to the US Bureau of Labor Statistics. While others studies have identified the reasons women leave engineering, this study focuses on women who persist in the profession. A complex, three stage mixed methods study has been conducted. The first stage was a qualitative research study based on semi-structured interviews with 31 women engineers, ten of whom had left an engineering career and 21 persisting for on average 21 years leading to a conceptual model and the development of a new construct to measure the ideal self. Next, a field experiment was conducted which surveyed 495 women ages 21 to 70 with engineering degrees. A structural equation model has been developed showing that women’s commitment to an engineering career is impacted by their levels of self efficacy, the interaction of age and number of children, and their ability to articulate a personal vision as operationalized by the ideal self. A woman’s relationship with her manager and level of work engagement also impact career commitment. The final stage of this research compared the factors and relationships important to a woman’s career commitment to engineering to a sample of 138 male engineers. Findings show that the factors important to persistence for women engineers have little or no impact on a man’s commitment to an engineering career. Women engineers have lower levels of self efficacy than men, and for men self efficacy has no statistically significant relationship to career commitment to engineering. Further both the relationship with the manager, one’s ideal self, and work engagement influence a woman’s career commitment to engineering more than for a man.

A conceptual model adapted from the intentional change theory (Boyatzis, 2008) is presented that integrates the findings from each of the studies to explain women’s persistence in an engineering career. The model describes a woman’s persistence in engineering as a complex system where a recursive relationship exists between the dynamic of the ideal self and the real self or between one’s dreams and one’s reality. The discontinuities involved with adapting and learning within an engineering career, the supporting nature of one’s relationships and the multiple levels of individual, family, organizational and occupational are shown as impacting career persistence.

The findings from this study can be used by both practitioners and scholars to design systems that that will enable sustainable careers for women in the engineering profession.

Committee:

Richard Boyatzis, PhD (Committee Chair); Diana Bilimoria, PhD (Committee Member); Toni Somers, PhD (Committee Member); Gary Wnek, PhD (Committee Member)

Subjects:

Engineering; Management

Keywords:

women engineer; STEM; gender; persistence; women&8217;s careers; Intentional Change Theory; ideal self

Childs, Sidney RobertImpact of the Student Support Services/TRIO Programming on Persistence and Academic Achievement
Doctor of Education (Ed.D.), Bowling Green State University, 2013, Leadership Studies
The purpose of this study was to determine what specific sets of TRIO Student Support Services (SSS) variables predict persistence and academic achievement using Astin's Input-Environment-Outcome (I-E-O) model. The model was employed to investigate the relationship among the following input variables of gender, race, eligibility for program services, and academic need for participation in the SSS program. Four environmental variables consisted of a select set of Bowling Green State University (BGSU) SSS services, namely advising, tutoring, math assistance, and writing assistance. The outcome variables were persistence and academic achievement. The sample for this study consisted of 1122 students who participated in the BGSU SSS program between 2005 through 2011. Logistic regression was applied to the data to examine the effect of the input and environmental variables on persistence and multiple regression was applied to the data to examine the association of the input and environmental variables on academic achievement as defined by grade point average (GPA). Findings suggest that the best-input variables of eligibility (first-generation only, low-income only, and first-generation/low-income) and need (low high school grades and failing grades) were significant in predicting student persistence. The environmental variables advising, tutoring, and assistance in math and writing were not predictors of persistence. However, writing and advising were significant predictors of GPA, with writing having a positive impact on this outcome. The input variables of gender and need were also significant predictors of academic achievement. Female students who persisted had a higher GPA than males. Students who entered the program because of failing grades and low high school grades had lower GPA than students with other levels of need. The overall models did not provide a substantial fit to predict persistence or academic achievement. Although this study provides some guidance as to which BGSU TRIO factors contribute to the outcomes of first-generation and low-income students, considerations for greater programming efforts, increased partnerships, and a review of organizational policies is presented. Recommendations for future research to gain a greater understanding of the myriad characteristics and experiences of first-generation and low-income students, the changing environment of higher education and the impact on students are offered.

Committee:

Patrick Pauken (Advisor); Angela M. Spence Nelson (Committee Member); Tyrone Bledsoe (Committee Member); Mark Earley (Committee Member); Judy Jackson May (Committee Member); William Knight (Committee Member)

Subjects:

Education; Education Policy; Higher Education; Higher Education Administration

Keywords:

higher education; persistence; academic achievement; TRIO; Student Support Services; first generation college students; low income students; Astin; I-E-O model

Hamilton, Rachel AnnEducating Across Difference: Underrepresented Groups, Graduate Program Integration, and Persistence-Related Attitudes among Clinical Psychology Doctoral Students
Master of Arts, Miami University, 2009, Psychology
Drawing on Tinto’s (1975, 1987, 1993) interactionalist model of student attrition, this survey study examined students’ cultural differences from dominant graduate communities, integration in graduate programs, and attitudes towards educational persistence. Cultural differences were assessed by a measure of cumulative diversity, which summed students’ number of memberships across traditionally underrepresented demographic groups. Integration was assessed by measures of advisor/mentor satisfaction and sense of community in the graduate program. Data from 330 doctoral students in APA-accredited clinical psychology programs showed that cumulative diversity had different effects by sex. Whereas cumulative diversity was unrelated to integration or persistence-related attitudes for women, it was related to less favorable integration and persistence-related attitudes for men. Integration, particularly sense of program community, was an important predictor of persistence-related attitudes for both genders. Sense of program community mediated the relationship between cumulative diversity and persistence-related attitudes for men only. Implications for student retention are discussed.

Committee:

William Stiles, Ph.D. (Advisor); Margaret O’Dougherty Wright, Ph.D. (Committee Member); Elisa Abes, Ph.D. (Committee Member)

Subjects:

Health Education; Minority and Ethnic Groups; Psychology

Keywords:

doctoral education; graduate programs; graduate students; clinical psychology; educational persistence; attrition; cultural diversity; minorities; traditionally underrepresented groups; interactionalist model; social and academic integration

Gonzales, Laura MarieLatino and Latina First Year College Students: Factors Important to Their Persistence
Doctor of Philosophy (Ph.D.), Bowling Green State University, 2006, Higher Education Administration
The purpose of this study was to gain an understanding of first-year Latino/a college students’ self-reported perceptions and experiences related to persistence and retention to the sophomore year. The focus was on Latino/a students who entered Bowling Green State University (BGSU), a mid-sized public regional state university in Ohio, in the fall semesters of 1998, 1999, 2000, and 2001. Pertinent issues related to the first-year Latino/a college student experience were addressed in this study: (a) demographic descriptors of entering and continuing Latino/a college students, (b) perceptions of their educational experiences, (c) educational and social concerns, and (d) factors related to their persistence. To answer the research questions, this study used a combination of quantitative and qualitative research methodologies. Descriptive statistics, such as frequencies, chi-square tests, and percentages, as well as t-tests and logistic regression were used to analyze the quantitative data. For the four year period, a total of 313 Latino/a students enrolled for their first year at BGSU. Two questionnaires developed by the Office of Institutional Research to administer to all new students were used to collect data for these students. Demographic and financial aid information were collected for the 313 students while 170 completed the BGSU First Year Student Questionnaire and 107 completed the New Student Transition Questionnaire. Emergent theme development guided the analysis of the qualitative data by interviewing four students who returned to BGSU for their second year. The combined analysis of the results revealed that there were some quantitative variables for which there where some significant differences between the persisters and the nonpersisters. The major themes from the interviews indicated that the participants were able to make the necessary social and academic adjustments as first-year students in order to thrive in the campus environment. Various forms of financial assistance, consisting of scholarships from the University as well as organizations affiliated with the high schools, and grants, were important to the students’ attendance and persistence. Recommendations made by the student participants and the researcher were included.

Committee:

Fiona MacKinnon (Advisor)

Subjects:

Education, Higher

Keywords:

Latino College Student Persistence

Anderson, BrentTask Persistence as a Predictor of Substance Abuse Treatment Outcomes
Doctor of Psychology (Psy.D.), Xavier University, 2016, Psychology
Substance abuse is associated with poor treatment retention and high relapse. However, positive substance abuse treatment outcomes are associated with time spent in treatment and treatment completion. As such, it is important to identify person variables associated with entering and completing treatment so those at risk for failure can be identified early and provided with additional supports. The current study examined the utility of a behavioral measure of task persistence—the Mirror-Tracing Persistence Task (MTPT)—to predict entering 28-day residential substance abuse treatment, completing treatment, and the number of completed days in treatment. The sample (N = 101) was comprised of individuals completing medically supervised detoxification; the majority (78%) were opioid dependent. The predictive power of the MTPT was tested in isolation and in the context of affective functioning. Furthermore, the relations between the theoretical construct of learned industriousness, task persistence and treatment outcomes were empirically tested. Results indicated that task persistence was significantly related to entering treatment but this relation was modest. Task persistence was not related to completing treatment or number of days of treatment completed. Counter to expectations, affective functioning and learned industriousness were not related to task persistence or to the primary treatment outcomes.

Committee:

Susan Kenford, Ph.D. (Committee Chair)

Subjects:

Psychology

Keywords:

Distress Tolerance; Mirror Tracing Persistence Task; Substance Abuse Treatment; Opiate Abuse; Learned Industriousness

Menting, JasonCan Performance-Based Measures Predict Binge Drinking? An Empirical Investigation
Doctor of Psychology (Psy.D.), Xavier University, 2013, Psychology
Heavy alcohol consumption and binge drinking are common among college students and can have adverse consequences (Wechsler, Lee, Kuo, & Lee, 2000). As such, it is important to identify those at the highest risk of consuming dangerous amounts of alcohol in order to implement preventative intervention strategies. The current study examined the predictive utility of performance-based measures of persistence, both physical (cold pressor) and psychological (mirror-tracing and anagram solution) in identifying those prone to binge drink and consume large quantities in a sample (N = 139) of college students. Individual difference factors, including affect regulation, distress tolerance, and impulsivity, were examined as possible mediators. The majority of the sample used alcohol (76.3%) and 54.0% reported binge drinking. Contrary to prediction, all forms of task persistence were unrelated to binge drinking or amount of alcohol consumed; however, lower persistence on the mirror-tracing task predicted meeting modified DSM-IV criteria for alcohol abuse (p = .03), suggesting that task persistence may be more related to alcohol problems rather than amount of alcohol consumed. Affect regulation and distress tolerance showed no direct effects. Impulsivity showed a modest direct effect but no indirect effects and did not mediate the observed relation between task persistence and problem alcohol use.

Committee:

Susan K. Kenford, Ph.D. (Committee Chair); Cynthia L. Dulaney, Ph.D. (Committee Member); Nicholas Salsman, Ph.D., ABPP (Committee Member)

Subjects:

Social Psychology

Keywords:

binge drinking; impulsive personality; college students; persistence

Brinkman, Nichole ESeasonal Dynamics and Relative Persistence Potential of the Enteric Species of Enterovirus in Wastewater
PhD, University of Cincinnati, 2014, Arts and Sciences: Biological Sciences
Human enteroviruses (EV) are a large group of enteric pathogens containing approximately 104 serotypes, which cluster into four different species (EV-A-D). They can be transmitted from infected to susceptible individuals via a person-to-person route, contaminated food and water used for recreation, shellfish harvesting, or drinking. Assessments of public health risk due to exposure to waterborne enteroviruses require, in part, an understanding of the levels of these pathogens in water sources. Two key factors in determining their occurrence in water are 1) knowing the extent of the diversity of this group present in a particular water source and 2) the ability of individual members to persist in water. Data published to date regarding presence and persistence potential of enteroviruses has been limited to poliovirus, and members of one of the four enterovirus species, leaving the majority of serotypes uncharacterized. The objectives for this project were to assess the diversity of enteroviruses present in wastewater and evaluate the influence that the persistence potential may have on the diversity profile. Towards this end, a method to concentrate representative enterovirus species was identified and determined to equally recover enterovirus species from primary effluent of wastewater. This method was then applied to monthly wastewater samples collected locally over a one year period for deep sequencing of enteroviruses present. This culture-independent, next-generation sequencing approach allowed for hundreds to thousands of enterovirus genomic sequences in each sample to be identified. Analysis of these sequences revealed that members of EV-A, EV-B and EV-C are present in each month of the year, while EV-D is present sporadically. EV-C is present in relatively low abundance year-round, while EV-A and EV-B alternate in predominance in a pattern that coincides with season. Investigation into the persistence potential of enteroviruses in wastewater shows that persistence cannot be described by species, but is serotype dependent. Poliovirus (EV-C) and enterovirus 70 (EV-D) were observed to be most persistent, while CVA10 (EV-A) was least persistent. The members of EV-B examined (CVA9, CVB1 and echovirus 30) showed moderate levels of persistence. The work described here provides a new perspective of the diversity profile of enterovirus present in wastewater and begins to decode the relative persistence potential of, until now, unrepresented members.

Committee:

Brian Kinkle, Ph.D. (Committee Chair); G. Shay Fout, Ph.D. (Committee Member); Eric Villegas, Ph.D. (Committee Member); Nicholas Ashbolt, Ph.D. (Committee Member); Dennis Grogan, Ph.D. (Committee Member)

Subjects:

Virology

Keywords:

enterovirus;wastewater;persistence

Jordan, Kari LIntervention to Improve Engineering Self-Efficacy and Sense of Belonging of First-Year Engineering Students
Doctor of Philosophy, The Ohio State University, 2014, EDU Teaching and Learning
The percentage of bachelor’s degrees in STEM awarded to women and underrepresented minority students needs to increase dramatically to reach parity with their majority counterparts. While three key underrepresented minority (URM) groups, African Americans, Hispanic/Latinos, and Native Americans constitute some 30 percent of the overall undergraduate student population in the United States, the share of engineering degrees earned by members of these groups declines as degree level increases. Underrepresented minority students accounted for about 12% of engineering bachelor’s degrees awarded in 2009, 7% of master’s degrees and 3% of doctorates (NSF Science Resource Statistics, 2009). The percent in engineering has been steadily decreasing, while overall participation in higher education among these groups has increased considerably. Keeping those thoughts in mind it is important to examine the historical theories and frameworks that will help us not only understand why underrepresented minority students pursue and persist in STEM majors in low numbers, but to also develop interventions to improve the alarming statistics that hamper engineering diversity. As indicated by our past two U.S. Presidents, there has been an increased discussion on the national and state level regarding the number of students entering engineering disciplines in general and underrepresented minority students in particular. Something happens between a student’s freshman year and the point they decide to either switch their major or drop out of school altogether. Some researchers attribute the high dropout rate of underrepresented minority students in engineering programs to low engineering self-efficacy (e.g. Jordan et al., 2011). A student’s engineering self-efficacy is his/her belief that he/she can successfully navigate the engineering curriculum and eventually become a practicing engineer. A student’s engineering self-efficacy is formed by mastery experiences, vicarious experiences, his/her physiological state, and social persuasions, such as student-professor interaction. Increasing the awareness of a student’s engineering self-efficacy could potentially improve sense of belonging and persistence for underrepresented minority students in engineering. The hypothesis of this study is that an intervention during the first semester of an incoming freshman’s tenure can help improve their engineering self-efficacy, sense of belonging, and overall retention in the engineering program. This study explored the following research questions: 1. What are the differences in engineering self-efficacy, and sense of belonging for first-year underrepresented minority engineering students compared to majority students? 2. What factors or variables should be considered and/or addressed in designing an intervention to increase engineering self-efficacy and sense of belonging amongst first-year underrepresented minority engineering students? 3. Can a small intervention during the beginning of the first semester improve a student’s sense of belonging, engineering self-efficacy, and student-professor interaction? Using the race, social fit, and achievement study by Walton and Cohen as a model, the author developed an intervention consisting of short compelling videos of upperclass engineering students from diverse backgrounds. In these videos, students discussed their pursuit of the engineering degree, what obstacles they faced in terms of sense of belonging and coping efficacy, and how they overcame those obstacles. Treatment groups of students watched the videos during the first few weeks of the semester, and pre and post tests were administered to measure mean gains in the student’s engineering self-efficacy, sense of belonging, and other variables. The results showed that underrepresented minority students had a lower sense of belonging than whites. The intervention used in the study contributed to mean gain increases in participants’ engineering self-efficacy, which could ultimately improve persistence. A single intervention did not show a significant increase in students’ sense of belonging; more work needs to be done to develop an effective intervention. The intervention is easily adaptable with insignificant cost, making it attractive for Minority Engineering Program (MEP) and other success program whose aim is to increase students’ engineering self-efficacy.

Committee:

Paul Post (Advisor); Lin Ding (Committee Member); Robert Gustafson (Committee Chair)

Subjects:

Education; Engineering

Keywords:

Engineering Self-Efficacy; Persistence; Underrepresented minority

Greene, Robert W."The effect of ability-based versus effort-based praise on task performance, task persistence, and internal factors in children identified as gifted or talented in mathematics"
Specialist in Education, Miami University, 2014, School Psychology
The purpose of this study was to further investigate possible differences that exist in the levels of task performance and task persistence exhibited by students identified as gifted in mathematics on a tiered mathematical task (i.e. Below, At, and Above the student's identified instructional level) when receiving either ability- or effort-based praise. Three 2nd grade students, identified as gifted/talented in mathematics, participated in the current study in a one-to-one setting with the examiner. In completing the tiered mathematical tasks, either ability- or effort-based praise was provided dependent on the testing condition. Each student's task-performance was assessed by recording the percentage of correct items on a mathematical task, while task-persistence was quantified by documenting the percentage of intervals each student was coded as on-task. Internal factors (attention, interest, and motivation) were measured for each student using a Likert scale self-report questionnaire. Findings suggest that overall: student task performance increased with exposure to effort-based praise, but decreased with ability-based praise; student task persistence increased with exposure to ability-based praise, but decreased with effort-based praise; and student internal factors increased with exposure to both effort- and ability-based praise, although effort-based praise had a stronger effect. Implications, limitations, and future research possibilities are presented.

Committee:

Amity Noltemeyer, Ph.D. (Advisor); Susan Mosley-Howard, Ph.D. (Committee Member); Jeffrey Wanko, Ph.D. (Committee Member)

Subjects:

Behavioral Psychology; Behavioral Sciences; Education; Education Philosophy; Educational Evaluation; Educational Psychology; Educational Tests and Measurements; Educational Theory; Experimental Psychology; Gender Studies; Mathematics; Mathematics Education; Psychology; Special Education

Keywords:

intrinsic motivation; verbal praise; internal factors; gifted; talented; giftedness; mathematics; task performance; task persistence; ability-based; effort-based; attention; interest; children; elementary

Somireddy, Upender ReddyEffect of Herbicide-Organic Mulch Combinations on Weed Control and Herbicide Persistence
Doctor of Philosophy, The Ohio State University, 2012, Horticulture and Crop Science
Integration of different weed control methods is essential to address the financial as well as environmental concerns being faced by nursery and landscape industry. Herbicide and mulch combinations have been suggested to achieve longer weed control in nurseries and landscapes. Field and laboratory experiments were conducted to determine the effects of herbicide formulations, mulch materials, depths of mulches, and herbicide placement relative to mulches on herbicide efficacy and persistence. Two field experiments were conducted, the first in the fall of 2006 and 2007 and the second in spring of 2007 and 2008. Granular and liquid formulations of a trifluralin+isoxaben mixture were applied alone and in combination with pine nuggets and hardwood mulch at three depths, 3-, 6-, and 12-cm. Granular herbicides were applied alone (without mulch) and above the mulch; and granular-pretreated mulches were also included. Liquid herbicides were applied alone, over the mulch, under the mulch, or as herbicide-pretreated mulches. Trifluralin and isoxaben in all formulations were applied at the rate of 4.48 kg ai/ha + 1.12 kg ai/ha, respectively. Mulch alone treatments and untreated control (no mulch, no herbicide) were also included. Visual weed control ratings and weed fresh weight data were collected at 30, 60, 90, and 120 days after treatment (DAT) for the spring experiment and at 180 and 210 DAT for the fall experiment. Visual ratings were based on a scale of 0 (no control) to 10 (complete control), with 7 and above being commercially acceptable. Selected treatments from the spring experiment, including the granular formulation alone, the liquid formulation alone, liquid formulation applied under 6-cm mulches, and the liquid formulation-treated mulches at 6-cm were used to investigate herbicide persistence. Herbicide residue analysis using liquid chromatography and bioassay studies using oats and radish were part of the herbicide persistence studies. All the treatments involving 6-cm and 12-cm mulch with or without herbicides provided efficacy ratings of above 7 in both experiments. Certain combinations of 3-cm mulch and herbicides, such as granular formulation over 3-cm pine nuggets, liquid formulation under 3-cm pine nuggets, and liquid formulation under 3-cm hardwood consistently provided at efficacy ratings ≥ 7 at all evaluation dates in both studies. This could be due to the longer residual activity of herbicides in those treatments. The time-course assay of herbicide dissipation in soil indicated that herbicides applied under the mulch persisted longer compared to herbicides applied alone. Results suggested that the persistence of herbicides largely depended on the physico-chemical properties of herbicides and mulches, as well as soil moisture and temperature. Weed control with greater mulch thickness could be largely due to the physical inhibition of weed germination and growth by the mulch, whereas at lower mulch thickness, the addition of herbicides to the mulch treatments was necessary to provide weed control equivalent to the thick mulch layer. Mulches applied at the 12-cm depth are expensive and can be detrimental to health of desirable plants, even though it provided almost complete weed control. Depth of mulches could be reduced to 3-cm from commercially recommended depths of 5- to 8-cm when herbicides were combined with mulches.

Committee:

Steven Harrison, Ph.D. (Advisor); John Cardina, Ph.D. (Committee Member); Terrence Graham, Ph.D. (Committee Member); Mark Bennett, Ph.D. (Committee Member)

Subjects:

Agricultural Chemicals; Agriculture; Agronomy; Environmental Science; Horticulture; Landscaping; Plant Sciences; Soil Sciences

Keywords:

weed control; herbicides; mulches; herbicide treated mulches; herbicide persistence

Yin, HanMOLECULAR ANALYSIS OF HTLV-2 APH-2 IN VIRAL TRANSFORMATION, PERSISTENCE AND HOST IMMUNE RESPONSE
Doctor of Philosophy, The Ohio State University, 2011, Molecular, Cellular and Developmental Biology
Human T-cell leukemia virus type 1 (HTLV-1) and type 2 (HTLV-2) are two closely related human retroviruses but they display distinct differences in pathogenicity. HTLV-1 causes adult T-cell leukemia (ATL) and HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP), whereas HTLV-2 appears much less pathogenic without conclusive disease association. Chapter 1 reviews important aspects of HTLV-1 pathobiology and highlights insightful comparative studies between HTLV-1 and HTLV-2. Chapter 2 and chapter 3 focus on APH-2, the antisense protein of HTLV-2, which shares functional homology to HTLV-1 HBZ as a negative viral regulator. In chapter 2, we investigated the contribution of APH-2 to HTLV-2-mediated immortalization of primary T-lymphocytes in vitro and HTLV-1 infection in a rabbit animal model. HTLV-2 APH-2 mutant viruses were generated and evaluated for viral gene expression, protein production, and immortalization capacity. In short-term proliferation and long-term immortalization assays, APH-2 mutant viruses were indistinguishable from wild-type HTLV-1 suggesting that APH-2 is dispensable for viral replication and cellular immortalization in culture. Rabbits inoculated with irradiated cells expressing HTLV-2 APH-2 mutant viruses became persistently infected. In addition, these rabbits displayed an increased antibody response to viral gene products and a higher proviral load in PBMCs as compared to wild type HTLV-2 infected animals. These observations indicate that APH-2 is not required for viral survival and persistence in vivo during the early stage of infection, which is contrary to what has been observed for HTLV-1 HBZ. To broaden our knowledge of the contribution of antisense proteins to HTLV biology, in chapter 3 we further examined the role of APH-2 and HBZ in regulating the host immune response. We found that both APH-2 and HBZ can potentially reduce type I interferon (IFN) production by inhibiting IFN regulatory factor 7 (IRF-7)-mediated gene transcription. This result indicates that HTLV-1 and HTLV-2 have evolved a common way to antagonize host immune attack upon viral infection. Chapter 4 focuses on the cellular tropism of HTLV-1 and HTLV-2 during the early stage after infection. In vivo, CD4+ T cells are the primary target cells for HTLV-1 in ATL patients even though CD8+ T cells serve as a natural reservoir in HAM/TSP patients and asymptomatic carriers. The HTLV-2 proviral burden has been shown to be higher in CD8+ T cells than in CD4+ T cells in infected individuals. Since most individuals are chronically infected at the time of detection, the early T cell preference of HTLV-1 and HTLV-2 in an immunocompetent host is not known. In chapter 4, we utilized the rabbit animal model to measure the early HTLV-1 and HTLV-2 proviral loads and gene expression patterns in purified CD4+ and CD8+ T cells over time. Our data indicate that the viruses do not exhibit cellular preference during the initial infection stage and the preferential transformation tropism is probably due to a selective clonal expansion during the clinical latency period. Collectively, the data presented in this thesis provides insights into the regulation of HTLV gene expression and the mechanism of cellular transformation and host-virus interplay.

Committee:

Patrick Green (Advisor); Michael Oglesbee (Committee Member); Marshall Williams (Committee Member); Li Wu (Committee Member)

Subjects:

Virology

Keywords:

HTLV; antisense protein; transformation; persistence; immune response

Duncan, Robin AStudents' Perceived Value of the Community College Experience: A Mixed Methods Study
Ph.D., Antioch University, 2018, Leadership and Change
The purpose of this study was to explore students’ perceived value of their community college experience and its relationship to other factors often related to student persistence in college, namely satisfaction, academic quality, service quality, and engagement. The research was guided by three focused questions: How do students describe and define perceived value of community college; what components emerge from exploratory factor analysis of items designed to measure perceived value; and how, if at all, is a student’s perception of the value of a community college experience different from related measures such as satisfaction, engagement, or quality? Data were collected from students enrolled at, primarily, three Massachusetts community colleges, employing a three-phased, mixed methods exploratory sequential approach. Phase 1 consisted of focus group interviews with students from one of the participating colleges to identify the themes and language for developing the perceived value construct. Phase 2 consisted of an online survey targeting currently enrolled community college students. Factor analysis identified key components of the perceived value scale and multiple regression analysis determined the relationship between perceived value and other control variables. Phase 3 consisted of a virtual post survey focus group with voluntary survey participants from Massachusetts community colleges to discuss and clarify the quantitative results and narrative survey responses. The dominant theme emerging from the findings was that students described perceived value as “I am valued” by the college. Results also indicated that the perceived value construct was different from other measures and suggested promising ways for further exploring and measuring student persistence. As a result of the study’s findings, a conceptual framework in the form of a Perceived Value Wheel was proposed with recommendations to community college leaders and practical contribution to higher education leadership and change. This dissertation is available in open access at AURA: Antioch University Repository and Archive, http://aura.antioch.edu/ and Ohiolink ETD Center, https://etd.ohiolink.edu/

Committee:

Jon Wergin, Ph.D. (Committee Chair); Carol Baron, Ph.D. (Committee Member); Ruth Slotnick, Ph.D. (Committee Member)

Subjects:

Adult Education; Behavioral Psychology; Behavioral Sciences; Behaviorial Sciences; Business Administration; Business Education; Community College Education; Community Colleges; Continuing Education; Education; Education Philosophy; Education Policy; Educational Evaluation; Educational Leadership; Educational Psychology; Educational Sociology; Educational Tests and Measurements; Educational Theory; Higher Education; Higher Education Administration; Management; Marketing; Organization Theory; Organizational Behavior

Keywords:

Perceived Value; Service Quality; Academic Quality; Satisfaction; Student Engagement; Involvement; Student Experience; Higher Education; Two Year Colleges; Community College; Students; Mixed Methods; Regression; Factor Analysis; Persistence; Retention

Coffman, Karie A.Persistence Redefined: Why Men Stay
Doctor of Philosophy in Urban Education, Cleveland State University, 2016, College of Education and Human Services
The research addressed factors affecting degree completion for adult male students. This qualitative case study explored factors that contributed to the persistence of undergraduate adult male students and their perception of their role within the campus community. The research considered: 1) how adult male undergraduate students described their ability to persist until degree completion; 2) what factors contributed to persistence; 3) what types of social interactions enabled participants to persist; and 4) how adult male undergraduate students described their relationship to the campus community. Data were collected through interviews with nine nontraditional male graduates who earned a baccalaureate degree within the last five years. The findings of this study showed that adult male students persisted by demonstrating grit. The campus community was about what they could contribute and the support they needed to graduate. The significance of this study demonstrated the need to consider the role of institutional resources in supporting mutual engagement and degree completion for adult male students.

Committee:

Catherine Monaghan, Ph.D. (Committee Chair); Marius Boboc, Ph.D. (Committee Member); Brian Harper, Ph.D. (Committee Member); Johnathan Messemer, Ph.D. (Committee Member); Peter Meiksins, Ph.D. (Committee Member)

Subjects:

Education; Higher Education

Keywords:

higher education; adult male students; nontraditional students; student persistence; grit; interactions; campus engagement

Carrubba-Whetstine, Christina R.INTEGRATING LOCAL AND ACADEMIC KNOWLEDGE: AN EXPLORATION OF LOW-INCOME AND WORKING-CLASS COLLEGE STUDENT EXPERIENCES EMPLOYING AUTOETHNOGRAPHY AND INDIGENOUS EPISTEMOLOGIES
Doctor of Philosophy, Miami University, 2015, Education
Low-income and working-class students have gained greater access to higher education, but their experiences on college campuses remain characterized by feeling devalued and excluded. Institutions of higher education privilege the reproduction of elite cultural values, beliefs, and ways of knowing and often marginalize low-income and working-class students by conceptualizing them as lacking and deficient. The present study abandons deficit conceptualizations of low-income and working-class college students operating from the assumption that they possess valuable local knowledge (i.e., knowledge gained from their family and local experience). The study explores how low-income and working-class students conceptualize, make sense of, and integrate their locally gained knowledge with their knowledge acquired from institutions of higher education. Data collection involved individual interviews, group interactions, and researcher autoethnographic writing. Inspired by Indigenous epistemologies and action/participatory research methods, the researcher engaged in the study as both researcher and participant. Participants were graduate students enrolled in a mid-size university located in the Midwest of the United States. Data analysis involved grounded theory methods and procedures (i.e., focused coding) and a collaborative theme development process with the study participants. Findings reveal that participants’ experiences challenge deficit conceptualizations of low-income and working-class students. Participants reported coming to college with extensive work experience that provided them with confidence and an ability to be both flexible and resilient. Participants communicated experiences of having their local knowledge and experiences marginalized by faculty, staff, and peers within the higher educational context. Though much of current scholarly research on low-income and working-class students focuses on their lacking of cultural capital, participants communicated feeling proficient in learning and performing the rules and norms of the university. Although participants revealed that their local and academic life remained separate throughout their undergraduate experiences (frequently having to make-sense of their academic experience for their families and their local experiences for the educational institution), in graduate school they felt compelled to integrate their local and academic knowledge and experiences by bringing their local narratives to the Academy. These findings and the overall research process encourages institutions of higher education to refocus their initiatives to support low-income and working-class students from supplementing and bolstering a seemingly deficient student to reevaluating their unwelcoming culture and environment.

Committee:

Peter Magolda (Committee Chair); Elisa Abes (Committee Member); Kathy Goodman (Committee Member); Ann Fuehrer (Other)

Subjects:

Adult Education; Education; Education History; Educational Leadership; Higher Education; Higher Education Administration

Keywords:

low-income; working-class; college students; autoethnography; Indigenous; epistemologies; local knowledge; academic knowledge, higher education; at-risk; persistence; resilience

Jackson, Patrick EEXAMINING CAMPUS AND STUDENT FACTORS THAT PREDICTED ACADEMIC PERFORMANCE AND INTENTION TO PERSIST FOR SUCCESSFUL AFRICAN AMERICAN AND LATINO STUDENTS AT FOUR-YEAR COLLEGES.
PHD, Kent State University, 2014, College and Graduate School of Education, Health and Human Services / School of Foundations, Leadership and Administration
This study examined the relationship of campus climate, institutional satisfaction, and academic adjustment in contributing to the academic performance and intentions to persist in college for successful African American and Latino students at traditional four-year colleges. Despite the dramatic increased enrollment of students of color in higher education, colleges’ strategies have failed to effectively and meaningfully increase the graduation rates for African American and Latino students (NCES, 2011). A national sample of responses on the Your First College Year survey (N = 5,559) was analyzed to describe the experiences and variables that contributed to perceptions of college campuses and academic outcomes for African American and Latino students. Methods included Exploratory Factor Analysis, Linear Regression Analysis, and Logistic Regression Analysis. Results identified the significance of: (a) Felt Discrimination on Campus; (b) Academic Self-Efficacy; (c) Sense of Belonging; and (d) Institutional Satisfaction on the academic performance and intentions to persist for respondents. This research is extremely timely because the outcry for more U.S. citizens with college credentials must include educational attainment for greater numbers of African American and Latino college students. Conclusions of this study suggest that colleges must understand and accept: (a) the needs of its changing demographics; (b) that African American and Latino students have unique needs; and (c) addressing those needs and expectations will increase student satisfaction, academic performance, and retention. Furthermore, discrimination continues to be pervasive on college campuses. Genuinely combating micro-aggressions on campus is essential to fostering a sense of belonging for students of color.

Committee:

Mark Kretovics (Committee Chair); Susan Iverson (Committee Member); Aryn Karpinski (Committee Member)

Subjects:

Academic Guidance Counseling; African American Studies; Black Studies; Continuing Education; Counseling Education; Demographics; Demography; Education; Educational Leadership; Higher Education; Higher Education Administration; Hispanic American Studies; Hispanic Americans; Multicultural Education; Social Research

Keywords:

African American; Black; Hispanic; Latino; college student; persistence; retention; academic performance; factor analysis; regression analysis; campus climate; institutional satisfaction; academic self-efficacy; sense of belonging; discrimination

Schmidt, Jessica LeeThe Effect Of Ability-Based Verse Effort-Based Praise On Task Performance And Persistence For Children With Giftedness
Specialist in Education, Miami University, 2012, School Psychology
The purpose of this study was to examine if there is a difference in students with giftedness in mathematics on task persistence and task performance on a tiered mathematical (e.g., Below, At, and Above the student’s capability level) task after receiving either ability- or effort-based praise. Four students in the 3rd grade that were identified as gifted/talented in mathematics participated in this study in a small group setting. While completing these mathematical tasks, either ability- or effort-based praise was delivered to the small group depending on the condition. Each student’s task performance was measured by the percentage correct on mathematical task. Each student’s task persistence was reported as the percentage of time the student was on task using the Behavioral Observation System. Results suggest task performance decreased with both the use of ability- and effort-based praise. Results also suggest that task persistence decreased when provided ability-based praise. Implications, limitations, and future directions are provided.

Committee:

Dr. Amity Noltemeyer (Advisor); Dr. Jason Abbitt (Committee Member); Dr. Michael Todd Edwards (Committee Member)

Subjects:

Education; Educational Psychology; Gifted Education; Mathematics Education

Keywords:

Task Performance; Task Persistence; Giftedness, Mathematics

Fisher, AdriaThe Effect of Ability-Based Verses Effort-Based Praise on Task Performance and Persistence for Children with Giftedness
Specialist in Education, Miami University, 2009, Educational Psychology
The purpose of this study was to examine the role that ability- and effort-based praise can play in persistence and task performance among children identified as gifted. Eleven middle school students who have been identified as gifted by their school district participated in non-academic activities determined individually by assessment to be of low- or high-interest. While completing these activities, either ability- or effort-based praise was delivered to the student depending on the condition. The effects of praise-type on the student’s task performance and persistence behavior were examined in relation to task interest level. Results suggest that the implementation of either praise type did not produce the negative effects on student’s persistence behavior and performance, regardless of initial task-interest.

Committee:

T. Steuart Watson, PhD (Advisor); Kevin Jones, PhD (Committee Member); Tonya Watson, PhD (Committee Member); Thomas Southern, PhD (Committee Member)

Subjects:

Educational Psychology

Keywords:

giftedness; task performance; task persistence; ability; effort; praise

Messina, John A.A Statistical Analysis of the Impact of Participation in Living-Learning Communities on Academic Performance and Persistence
Doctor of Education, University of Akron, 2011, Educational Leadership

This study sought to determine if participation in the living-learning communities at a large, Midwestern, urban institution in 2004, 2005, and 2006 had an impact on performance and retention through the college career by yielding differences in academic performance and persistence measures. This study sought to broadly determine, when considering academic year and controlling for entering ability, whether there is a statistically significant difference, on average, in the fifth year of academic performance and retention rates of living-learning community participants, learning community participants, traditional curriculum resident students, and traditional commuter students.

When considering persistence as measured by cumulative credits earned and academic performance as measured by grade point average, analysis of variance (ANOVA) was used to identify statistically significant differences between groups when considering academic year. Analysis of covariance (ANCOVA) was conducted to assess these differences when considering academic year and controlling for entering ability measures of high school GPA and ACT score. ANOVA results indicated differences in credits earned and cumulative grade point average between curriculum types. In each instance, living-learning communities exceeded all other groups. ANCOVA results indicated that there were statistically significant differences, on average, between groups for credits earned and cumulative grade point average when controlling for entering ability variables. Of interest, results identified adjusted means of cumulative grade point average for living-learning communities and residents as being near equivalents.

Unique to the study, was the focus on analysis after five years of study, assessing the longitudinal impact associated with participation in living-learning communities. Results identified that the interaction between year and curriculum type were not significant, indicating that there was not a statistically significant difference among the students’ grades and credits earned across the three years of the study. Achievement patterns did not differ by year, reflecting living-learning communities earned higher scores in each cohort and showed that curriculum type served as the only significant factor in the analysis. The study adds breadth and depth to institutional approaches to assessing programs which impact both academic performance and persistence as measures of academic success.

Committee:

Sandra Coyner, Dr. (Advisor); Sharon Kruse, Dr. (Committee Member); Xin Liang, Dr. (Committee Member); Megan Moore-Gardner, Dr. (Committee Member); Robert Schwartz, Dr. (Committee Member); Laura Gelfand, Dr. (Committee Member)

Subjects:

Educational Evaluation; Higher Education; Higher Education Administration

Keywords:

living-learning communities; academic perfomance; persistence; learning community; resident students

Briju, Betsy J.Progress of Work towards Cloning Gravity Persistence Signal (gps) Mutants by PCR-Based Methods and Positional Mapping
Doctor of Philosophy (PhD), Ohio University, 2011, Environmental and Plant Biology (Arts and Sciences)
Gravitropism is a growth response that enables a plant to orient its organs for efficient utilization of natural resources. A change in the gravity vector is sensed by the plant when statoliths sediment towards the new bottom of the cell. As a result, asymmetric distribution of auxin occurs, leading to differential growth. The signaling events that link statolith sedimentation and asymmetric auxin transport are still not well known. Gravity Persistence Signal mutants are a class of T-DNA tagged Arabidopsis mutants potentially defective in the signal transduction events. This research was aimed at identifying the genes altered in these mutants and thereby understanding the function of these genes in the process of gravitropism. PCR based methods such as Thermal Asymmetric Interlaced (TAIL) PCR, inverse PCR and adaptor ligation methods have been used to identify the flanking regions of the T-DNA insertion in gps2 and gps6. Although gps2 is no longer Kanamycin resistant, there is evidence that a part of the tag remains intact. The T-DNA tags in three of these mutants seem to have extended regions integrated beyond the canonical left border. PCR results also indicated a possibility of tandem tags. Southern hybridization results provide further evidence that gps5 and gps6 may have more than one T-DNA tags. The current knowledge on the T-DNA ends in both gps2 and gps6 suggests that a unique T-DNA region among the tandem tags, is present that would prove helpful in using modified PCR-based methods to identify the mutated genes. A F2 mapping population has been generated for map-based cloning of gps2 and gps6. Upon identification of homozygous plants in the F2 segregating population, screening for linked markers can be done from among the chosen 26 markers. If a pair of flanking markers are identified that are located on the same BAC or PAC, candidate genes could be found in their vicinity and therefore analyzed. Alternately, deep sequencing could be adopted to identify the candidate genes in the vicinity of these markers. Identification of GPS2 and GPS6 will help in delineating mechanisms that provide a sense of direction to the graviresponding plant.

Committee:

Sarah Wyatt, PhD (Advisor); Ahmed Faik, PhD (Committee Member); Allan Showalter, PhD (Committee Member); Frank Horodyski, PhD (Committee Member)

Subjects:

Cellular Biology; Molecular Biology; Plant Biology

Keywords:

Gravitropism; T-DNA insertion; Molecular mapping; Gravity persistence signal; Feldmann T-DNA; Bimolecular Fluorescence Complementation

Next Page