Despite a number of recent studies focused on the issue, patterns of stream insect dispersal in temperate streams of North America remain poorly understood. Movement of benthic invertebrates is notoriously difficult to measure directly using traditional means; however, genetic markers provide an ideal method for estimating stream insect dispersal. In this study, the control region of mitochondrial DNA was used to study gene flow and dispersal among populations of the stonefly <i>Peltoperla tarteri</i> in the Southern Appalachians. The control region of <i>P. tarteri</i> is approximately 1270 base pairs (bp) in length, 81% AT-rich, and contains variable numbers of a 74 bp tandem repeat containing the sequence motif "5'-GGGGGC-3". Many stream insects have long life cycles that result in the simultaneous existence of multiple cohorts throughout the larval development period. If larval development is fixed, genetic isolation among cohorts may confound genetic estimates of dispersal. Although larval head width data indicated that <i>P. tarteri</i> is semivoltine in southwestern Virginia, low levels of genetic differentiation among cohorts suggested that larval development of <i>P. tarteri</i> is not fixed and that some individuals complete development in one or three years rather than two. This 'cohort splitting' would result in individuals from distinct cohorts maturing at the same time and mating with one another. Such developmental plasticity may allow some individuals to avoid adverse environmental conditions. The extent and likely mechanism of dispersal was determined by comparing levels of population genetic differentiation within drainages to that among drainages. While there was no consistent relationship between genetic and geographic distance, genetic differentiation was generally high within and among drainages. Nested clade analysis indicates that historical fragmentation and range expansion coupled with contemporary gene flow explain the present day pattern of genetic variation in <i>P. tarteri.</i> In order for these historical patterns to have such a strong influence on present day genetic structure, both larval and adult dispersal must be restricted. However, the genetic data suggest that larval dispersal is more frequent than adult dispersal. / Ph. D.

Briery Creek Lake (BCL) has low abundance of young largemouth bass (LMB) compared to Sandy River Reservoir (SRR), which could jeopardize the trophy-LMB management goal in BCL. I assessed factors that may limit recruitment of LMB in BCL: angling, predation, competition, growth, and food availability. Age-0 LMB were monitored from nesting through their first summer with nest surveys, light traps, and electrofishing. Nesting success was higher in BCL (53%) than SRR (31%). Initial light trap catch-per-unit-effort (CPUE) was higher in BCL than SRR but, by July, light trap and electrofishing CPUE was higher in SRR than BCL. LMB nest success, growth, and CPUE did not differ between areas in BCL that were experimentally closed and areas left open to angling. Predation on age-0 LMB did occur in BCL, but was not higher than predation in SRR. Diet overlap between age-0 LMB and bluegill in BCL was >60% during June, indicating potential for competition. Zooplankton samples indicated that density of copepods was similar between reservoirs (2.3/liter); however, the average size of copepods was smaller in BCL (0.42 mm) than SRR (0.71 mm). I examined the activity of trypsin, which digests and converts protein. Trypsin activity was lower in BCL than SRR on 23 and 27 June, indicating that a nutritional deficiency exists for age-0 LMB in BCL. This deficiency was likely caused by the reduced zooplankton size in BCL and led to slower growth of age-0 LMB during June in BCL (0.8 mm/day) than SRR (1.2 mm/day). The fact that age-0 LMB CPUE in BCL dropped lower than SRR by July, despite BCL having a greater nesting success and higher CPUE in early June, indicates that a recruitment bottleneck for LMB occurred in June. Maintaining the trophy LMB fishery in BCL requires management options that consider the factors in June that affect recruitment. I recommend decreasing the presently overabundant aquatic macrophytes in BCL, thus allowing for increased nutrient availability for phytoplankton, the primary food source of zooplankton. This could increase the density and size structure of zooplankton, and thereby increase food availability for age-0 LMB. / Ph. D.

The early life history dynamics of stocked, fingerling striped bass (Morone saxatilis) were evaluated in Smith Mountain Lake, Virginia, from 1994-96 and incorporated into an individual-based model to assess various stocking strategies in terms of their largest percent increases in first-year growth, overwinter survival, and recruitment to age 1. Age-0 striped bass exhibited dissimilar patterns of dispersion and size-dependent spatial distribution as a result of differences in habitat availability between stocking sites and water temperature preferences. Although size increased over the growing season, a bimodal length distribution developed by fall during both 1994 and 1995; this distribution consisted of large-mode juveniles (> 180 mm TL) that weighed several times more than small-mode fish (<140 mm TL). Differential growth was attributed primarily to size-dependent differences in food habits and diet quality: small-mode striped bass maintained a mixed, low quality diet of invertebrates and small, age-0 cyprinids, while large-mode juveniles consumed only larger, energetically more profitable age-0 alewives. This disparity in food habits, largely due to the inability of small-mode striped bass to consume distributionally- and morphologically-invulnerable age-0 alewives, resulted in size-dependent differences in physiological well-being as large-mode juveniles had amassed greater absolute energy stores than small-mode fish by the end of the growing season. Spring sampling revealed that the bimodal length distribution had become unimodal and was comprised almost entirely of large-mode juveniles. Because the few surviving small-mode striped bass collected during spring were extremely emaciated, it appears that this size group exhausted their energy stores and, consequently, starved over the winter. Individual-based model simulation results indicated that stocking juvenile striped bass at a median total length of 52 mm on 08 June, while maintaining the current stocking density at 300,000 fingerlings, would result in the largest percent increases in first-year growth, survival, and number of age-1 recruits. This strategy was also less sensitive to perturbations in alewife population parameters and water temperature regime, and was more robust to these variations than the existing stocking scheme (300,000 fingerling striped bass with a median total length = 42 mm introduced on 15 June). / Ph. D.

Blood vessels are critical for the delivery of oxygen and nutrients to all cells in the body. To properly function, blood vessels and their primary components must develop and mature into a healthy network, capable of dynamic alterations to meet new needs of the body. The early genetic and molecular programs that "push" the vasculature to develop are the same programs that reactivate when there are normal changes to the body such as injury, muscle growth or decline, or aging; and when pathologies arise like cancer, stroke, and diabetes. Therefore, it is crucial to understand how the vasculature develops into a healthy system by studying all components as they mature. Endothelial cells that comprise the vessels themselves are joined by specialized partner cells called pericytes that help guide and mature vessel growth. Pericytes lie elongated along endothelial cells and have multiple points of contact with the endothelium. In this position, pericytes assist in cell-cell communication and even blood flow regulation in the microvasculature. To study the relationship between endothelial cells and pericytes during development, we observed vascular morphology in three and four dimensions, as well as the genetic and molecular mechanisms underlying how these cells are recruited and interact in several experimental models. Thus, to thoroughly analyze the morphology of these vessels, we developed a rigorous methodology using a MATLAB program to determine the colocalization and coverage of pericytes associated with vessels in large image sets. After developing analytical methods to investigate all the components of the blood vessel wall, we expanded our investigation of how pericytes and other aspects of microvasculature develop in animal models, specifically a more commonly used murine model for vascular development and for treatment of human diseases. Our findings of vascular development in mice suggest that there are important differences in how human and mouse brain blood vessels form. Therefore, studies using mice must be carefully designed to account for these discrepancies. Additionally, research into why human and mouse neurovascular development and maturation are different can aid in the development of improved experimental models to better treat human pathologies. / Doctor of Philosophy / Blood vessels have the crucial job of delivering oxygen and nutrients to all the cells in the body. To perform this duty, blood vessels- and the components that make them- must develop and mature into a healthy network, capable of altering itself to meet new needs of the body. The early programs that “push” the vessel system to develop are the same programs that reactivate when there are normal changes to the body such as injury, muscle growth or decline, or aging; and when abnormal diseases arise like cancer, stroke, and diabetes. Therefore, it is critical to understand how blood vessels develop into healthy systems by studying all of their components as they mature. Endothelial cells that comprise the vessels themselves are joined by specialized partner cells called pericytes that help guide and mature vessel growth. Pericytes lie elongated along endothelial cells and have multiple points of contact with the endothelium. In this position, pericytes assist in cell-cell communication and even blood flow regulation in smaller vessels called capillaries. To study the relationship between endothelial cells and pericytes during development, we observed vascular anatomy in three and four dimensions, as well as mechanisms underlying how these cells come together and interact in several experimental models. Thus, to thoroughly analyze the morphology of these vessels, we developed a rigorous methodology using a MATLAB program to determine the colocalization and coverage of pericytes associated with vessels in large image sets. After developing analytical method to investigate all the components of the blood vessel wall, we expanded our investigation of how pericytes and other aspects of blood vessels develop in animal models, specifically a more commonly used animal model for vascular development and for treatment of human diseases. Our findings of vascular development in mice suggest that there are important differences in how human and mouse brain blood vessels form. Therefore, studies using mice must be carefully designed to account for these discrepancies. Additionally, research into why human and mouse neurovascular development and maturation are different can aid in the development of improved experimental models to better treat human illness and injury.

The purpose of this thesis is to investigate how the price of advertising space affects the demand for help-wanted advertising. To do so, this thesis develops and estimates an econometric model to explain and predict the demand for help-wanted advertising placed in a newspaper. For the most part, economic theory and the literature suggest that basic economic and demographic factors explain the demand for help-wanted advertising. The literature and empirical studies confirm an inverse relationship exists between unemployment rates and help-wanted advertising. This thesis confirms these findings using firm specific data for a major metropolitan newspaper. Surprisingly few other studies explore whether the price for advertising is also an important determinant of demand. My model includes both unemployment data and average price of help-wanted ads and finds that price is an important determinant for the demand for help-wanted advertising. Closer scrutiny of these relationships should remove some of the uncertainty associated with what now appears to be a volatile demand. / Master of Arts

In addition to recruitment pressures felt by all in higher education, community colleges have the unique challenge of communicating with students of all ages, interests, and academic levels, and doing so with limited staff and resources. Many recruiters have turned to social media as an important tool for reaching potential students. However, for community colleges with few staff, social media communication can be difficult and time-consuming. This study explores how community college administrators are using social media as a recruitment tool, and how this use aligns with students' needs and expectations. This two-part study employs uses and gratifications theory to guide qualitative interviews with the social media administrators at three Virginia community colleges and focus groups with current students at each of the colleges. This study takes a unique approach to theory by comparing the uses and gratifications of both the message creator and user. Social media administrators at the community colleges were found to use social media to gratify their awareness, recruitment, and reach/engagement needs. Students thinking about the recruitment process were found to expect community colleges' social media content to gratify their needs for socialization, discovery, and access. Administrators are meeting many of the students' reported social media recruitment needs but could use the data provided in this study to improve their social media efforts in a few emerging areas. / Master of Arts

Since the introduction of hybrid striped bass M. chrysops x M. saxatilis to Claytor Lake, Virginia in 1993, relative abundance of striped bass Morone saxatilis has dropped disproportionately to stocking density. Potentially deleterious interactions between the two fishes that may limit recruitment to age 1 were considered in terms of trophic relationships, physiological indices of health, overwinter survival, and post-stocking predation. Both fishes preferred habitat types characterized by structure-free sand or gravel substrates, but striped bass and hybrid striped bass did not exhibit significant diet overlap during the growing season. At a total length of approximately 120 mm, the juvenile moronids shifted from a mixed diet of zooplankton and invertebrates to a diet comprised primarily of age-0 fishes. However, after becoming piscivorous striped bass preyed primarily upon age-0 alewife Alosa pseudoharengus, while hybrid striped bass consumed age-0 sunfishes. Striped bass achieved mean total lengths of 229 and 173 mm by the end of the growing season in 2001 and 2002, respectively. Stocked into the reservoir three months later than striped bass, mean hybrid striped bass total lengths reached 133 mm at the end of the 2002 growing season. Condition factor, relative weight, and lipid index values were low, but nearly equivalent for both striped bass and hybrid striped bass throughout this study. Overwinter starvation of smaller (< 150 mm total length) striped bass was observed for the 2001-2002 sampling season. Predation upon stocked fingerlings was not considered significant in limiting juvenile survival; only three fingerling moronids were found in the examination of stomach contents of 200 potential predators captured near stocking sites. It does not appear that resource competition with hybrid striped bass during the growing season resulted in increased overwinter mortality of juvenile striped bass. Delayed stocking of hybrid striped bass lessens the potential for trophic competition between striped bass and hybrid striped bass at this early life-stage. / Master of Science

The purpose of this study was to investigate the perceptions of teachers and administrators in a rural southeast school district regarding the impact of strategic compensation as a motivating factor on teacher quality, recruitment, and retention. As a result of increased demands on K12 education and the limited pool of teaching candidates, public school districts continue to search for ways to motivate, recruit and retain teachers (Muranto and Shuls, 2012). Since many view the traditional teacher salary scale as an outdated and ineffective practice, school districts continue to search for new ways to provide additional financial bonuses. (Springer, 2009). At the time of the study, the rural southeast school district studied was the only district within its state that used a strategic compensation model as a part of its employee benefits package. The locally funded plan awarded bonuses to teachers who qualify according to the parameters set by their school board. The initial rationale behind the implementation of the plan was to acknowledge exemplary teachers within the district. In this study, the history of the traditional salary scale, teacher quality, teacher retention, teacher recruitment, proponents and opponents of strategic compensation and recent studies on merit pay were examined. In this mixed methods study, a survey was sent to all 237 candidates eligible for strategic compensation, and a focus group interview with 7 administrators responsible for the summative evaluations of teachers was conducted. After the data were collected, descriptive statistics were examined to determine if additional ANOVA analyses were required to determine if demographic differences could be identified. The findings from this study may assist school districts develop and maintain a strategic compensation plan as a part of its overall teacher compensation package. After the data were disaggregated and analyzed, the findings from this study indicated mixed reviews regarding teacher perceptions of strategic compensation. Survey results indicate that the ideal bonus lies between $1,000-$3,000. In addition, teachers and administrators did not perceive that strategic compensation assisted with teacher recruitment or retention. Additional findings indicated differences in perceptions of strategic compensation based on gender and level of teaching assignment. / Doctor of Education / The purpose of this study was to investigate the perceptions of teachers and administrators in a rural southeast school district regarding the impact of a pay for performance plan as a motivating factor on teacher quality, recruitment, and retention. As a result of the teacher shortage in America, public school districts continue to search for ways to motivate, recruit and retain teachers. Since many view the salaries of teachers low, school districts continue to search for new ways to provide additional end of year bonuses as a motivating factor to improve teacher quality, recruitment and retention. To date, the rural southeast school district studied is the only district within its state that uses a strategic compensation model as a part of its employee benefits package. The plan awards bonuses to teachers who qualify according to their end of year rating. In this study, the history of the traditional salary scale, teacher quality, teacher retention, teacher recruitment, proponents and opponents of strategic compensation and recent studies on merit pay will be examined. A survey was sent to all 237 candidates eligible for strategic compensation, and a focus group interview with 8 administrators responsible for the summative evaluations of teachers was conducted. After the data were collected, they were sorted by demographic identifiers to determine if there were differences in responses between different groups. The findings from this study may assist school districts develop and maintain a strategic compensation plan as a part of its overall teacher compensation plan. The findings from this study include: $1,000-$3,000 is the ideal amount of money that would motivate a teacher to improve, strategic compensation did not assist with teacher recruitment, and school administrators did not believe strategic compensation led to greater teacher retention within the rural southeast school district. In addition, teachers and administrators believed that participation in the strategic compensation plan should be voluntary. Findings based on demographic identifiers indicated that male teachers responded more positively than female teachers, and there were differences among elementary, middle school and high school teacher responses with regard to their perceptions of the strategic compensation plan.

Mental health is an important part of college students' experiences, and more administrators are paying attention to mental health issues (Cooper, 2000; Kitzrow, 2003). Self-esteem is central to mental health (Kittleson, 1989), and can be attributed to social situations, especially those that deal with rejection (Bednar, Wells, & Peterson, 1989; Caunt, 2003; Eisenberger & Lieberman, 2004; Steffenhagen & Burns, 1987). Sorority recruitment is an event that includes rejection (National Panhellenic Conference, n.d.), and may negatively affect self-esteem. The purpose of this study was to determine how recruitment affects the self-esteem of participants. First, this study sought to determine if self-esteem changes during recruitment for two groups of Potential Members (PMs): those who complete recruitment (persistent PMs) and those who withdraw (withdrawn PMs). Second, this study investigated how self-esteem differed at the start and end of recruitment between these groups. The sample included 336 potential sorority members at a large state institution. Data were collected by administering the Rosenberg Self-Esteem Scale (Rosenberg, 1979) twice: once before recruitment, and again when the PM either withdrew or completed the process. The results of the study indicate a significant change in self-esteem during recruitment. The persistent PMs experienced an increase in self-esteem; the withdrawn PMs experienced a drop in self-esteem. Also, there was a difference between the self-esteem levels of the two groups at the start of recruitment; the withdrawn PMs had a higher self-esteem than the persistent PMs. There was no difference in self-esteem at the end of the recruitment process. / Master of Arts

Diversifying the physician workforce is crucial for addressing healthcare disparities. Despite efforts to promote diversity, residency programs still have low representation of Black/African Americans. Our research, drawn from articles in the Temple University Libraries Database and Google Scholar Database up to March 2024, highlights differences in perceptions of program culture and racial diversity between URIM and non-URIM applicants. URIM applicants consider factors such as the authenticity of diversity, equity, and inclusion (DEI) efforts, as well as the racial climate when evaluating programs. Additionally, representation of URIM faculty and residents along with post-interview communication and events are important factors when assessing residency programs. There is limited literature on how Black/African American applicants' preferences influence diversity recruitment efforts. It is imperative for programs to incorporate feedback from URIM applicants to develop effective recruitment strategies and foster cultural shifts. By doing so, we can contribute to a more diverse and inclusive physician workforce capable of more effectively addressing health disparities that disproportionately affect Black/African Americans. / Urban Bioethics