Master of Science / Department of Family Studies and Human Services / Karen S. Myers-Bowman / The current study focuses on qualitative data collected from youth and adults in two rural Kansas communities. The focal point of analysis was youth and adults' answers to questions about their experiences working with one another within community-based programs, specifically questions regarding youth's feeling of empowerment within the context of the program. Lerner's theory of developmental contextualism provided a framework for understanding how youth-adult relationships contribute to the development of youth empowerment. Youth voice, a construct related to the youth empowerment literature, appeared in the participants' responses across program sites. Common themes across settings were that teens who had been involved in the program the longest felt especially empowered, that youth became more responsible as a result of participating in the program, and that adults in both program sites fulfilled the six adult roles for youth empowerment that have been established in the research literature. Finally, three constructs significant in the youth development literature (confidence, connection and compassion) emerged as themes in relation to the experiences of the young people in the program. Implications of this study include exploring the impact youth-adult relationships have on adults and investigating how teens as role models or mentors for "littles" impact their feeling of empowerment. Suggestions for replication of this study are also given.

Doctor of Philosophy / Department of Biochemistry / Subbaratnam Muthukrishnan / In order to grow and develop, insects must undergo a process of molting, wherein the old cuticle is replaced with a new one. A thin envelope layer has been predicted to act as a physical barrier between molting fluid chitinases and the site of new chitin synthesis ensuring selective protection of newly synthesized chitin. The factors that help the new exoskeleton withstand the deleterious effects of chitinolytic enzymes remain poorly understood. In the current study a mechanistic role for two proteins, Knickkopf (Knk) and Retroactive (Rtv), was explored in organization and protection of the newly synthesized procuticular chitin. Our study demonstrated colocalization of molting fluid chitinases (chitinase-5) with chitin in T. castaneum pharate adult elytral cuticle. Presence of chitinases in the new cuticle, disproved the old theory of the envelope being a protective barrier against chitinases. Confocal and transmission electron microscopic imaging of T. castaneum pharate adult elytral cuticle suggested that Knk protein selectively colocalizes with chitin in the new procuticle, organizes chitin into laminae and protects it from the activity of molting fluid chitinases. Down-regulation of Knk expression resulted in reduction of procuticular chitin, disruption of the laminar architecture of the procuticle and severe molting defects that are ultimately lethal at all stages of insect growth. The presence and activity of Rtv protein ensures the trafficking of Knk into the procuticle. Down regulation of Rtv transcripts showed molting defects and a significant decrease in chitin content similar to those following Knk dsRNA treatment. Confocal microscopic analysis revealed an essential role for Rtv in proper trafficking of Knk from epithelial cells to within the newly synthesized procuticule. Once released into the procuticle, Knk organizes and protects chitin from chitinases. The conservation of Knk and Rtv in all insect species suggests a critical role for these proteins in maintenance and protection of chitin in the insect exoskeleton.

Nlrp5, a maternal-effect gene, is required for embryonic progression and female fertility in mice. Previous work indicated an age-related decline in Nlrp5 transcripts in murine oocytes. As maternal age is associated with increased spindle organization defects, studies in this thesis focused on the analysis of meiotic spindle defects in oocytes of Nlrp5-deficient mice. NALP5 protein showed a novel kinetochore-localization pattern, which was disturbed by spindle poisons. Nlrp5-deficient oocytes displayed a higher frequency of spindle abnormalities and chromosomal misalignment. Upon fertilization, these defects translated into increased incidences of multinucleation. As these phenotypes are associated with deficiencies in genome stability, we examined spindle assembly checkpoint (SAC) components. We found that numerous SAC proteins were dysregulated, implying that NALP5 may be critical in sensing oocyte-related SAC defects. We found that Nlrp5-deficient oocytes may have increased DNA damage. Thus, Nlrp5 may be an integral component responsible for preservation of genome integrity in female gametes.

Nlrp5, a maternal-effect gene, is required for embryonic progression and female fertility in mice. Previous work indicated an age-related decline in Nlrp5 transcripts in murine oocytes. As maternal age is associated with increased spindle organization defects, studies in this thesis focused on the analysis of meiotic spindle defects in oocytes of Nlrp5-deficient mice. NALP5 protein showed a novel kinetochore-localization pattern, which was disturbed by spindle poisons. Nlrp5-deficient oocytes displayed a higher frequency of spindle abnormalities and chromosomal misalignment. Upon fertilization, these defects translated into increased incidences of multinucleation. As these phenotypes are associated with deficiencies in genome stability, we examined spindle assembly checkpoint (SAC) components. We found that numerous SAC proteins were dysregulated, implying that NALP5 may be critical in sensing oocyte-related SAC defects. We found that Nlrp5-deficient oocytes may have increased DNA damage. Thus, Nlrp5 may be an integral component responsible for preservation of genome integrity in female gametes.

This study examined the impact of working memory deficits (WMD) on the academic achievement of adolescents with ADHD. Adolescents (n=79) aged 13 to 17 years with a clinical diagnosis of ADHD were subtyped into those with and without WMD based on impairment in at least two measures, and then compared on their academic achievement and clinical profile. Results indicated that adolescents with ADHD plus WMD (23%) manifest significantly lower academic achievement than those with adequate WM. By contrast, there were no group differences in psychiatric comorbidity, severity of ADHD symptoms and psychological adjustment. We also found a unique contribution of WM to academic achievement over and above that of other clinical features. These findings suggest that WMD compromise the educational attainment of a subgroup of individuals with ADHD. Individuals with ADHD should be screened for WMD to prevent academic failure and WM should be considered as a treatment target.

Introduction: Les stratégies d’optimisation de la performance chez les athlètes sont de plus en plus exploitées par les entraîneurs et préparateurs physiques. La potentialisation de post- activation (PAP) est reconnue comme étant un phénomène pouvant mener à une augmentation des performances. L’objectif de la présente étude était de donc décrire les effets d’une pré-sollicitation à la hanche sur la coordination inter-musculaire et la performance au cours d’un exercice épuisant. Méthodes: Six athlètes de patins de vitesse de courte piste (3 de sexe masculin et 3 de sexe féminin; âge: 20.2 ± 2.8 ans; moyenne±écart-type) ont exécuté aléatoirement un exercice qui consistait en 2 séries de 9 blocs de squats sautés maximaux, entre-coupés d’un squat isométrique d’une durée de 5 secondes sans pré-sollicitation préalable (CON) et avec une tâche de pré-sollicitation unilatérale de squat isométrique (EXP) contre une barre fixe de 2x3 secondes. Le pic de puissance moyen, l’amplitude et la fréquence moyenne d’EMG, et la vitesse et l’accélération angulaires des premiers et derniers blocs étaient enregistrés. Résultats: La pré-sollicitation isométrique maximale des membres inférieurs n’a pas amélioré de manière significative la performance de sauts et la coordination des muscles stabilisateurs à la hanche. La fréquence spectrale moyenne a néanmoins témoigné de l’implication de stratégies compensatoires du membre inférieur gauche en réponse à la fatigue. Conclusion: La pré-sollicitation des stabilisateurs à la hanche n’augmenterait pas la performance de squats répétés. Par contre, la fréquence moyenne du grand fessier et du tibial antérieur gauche ont suggéré meilleure résistance à la fatigue des muscles du membre inférieur non-dominant avec une pré-sollicitation. Les résultats de la présente étude indiquent donc la pertinence de considérer la pré-sollicitation dans un objectif de performance et de réadaptation sachant que l’asymétrie est omniprésente chez les athlètes et qu’elle est impliquée dans le taux élevé de blessures enregistré chez cette population. / Introduction: Strategies in order to optimize athlete’s performances are commonly used by coaches and trainers. Post-activation potentiation (PAP), occurring after a pre-activation, is known to be a phenomenon that can lead to an increase in force and power production and thus, performance. The aim of the present study was to describe the effects of a hip stabilizers pre-activation on multi-segment coordination and performance during a fatiguing exercise. Method: Six short-track speed skating athletes (3 males and 3 females; age: 20.2 ± 2.8 years; data reported as mean ± SD) participate in the study were they had to execute 2 sets of 9 blocks of 6 maximal squat jumps with 5 s isometric squats between blocks and 5 min rest between sets without (CON) or with (EXP) a 2x3s unilateral isometric squats against a fixed bar potentiating exercise 5 min before to the first set of 9 blocks intending to target the lower body hip stabilizers, flexors and extensors. Jumping average peak power, EMG amplitude, median frequency, angular velocity and acceleration were measured. The first and last blocks of jumps were recorded for each set. Results: There were no significant difference between conditions, as results showed an overall fatigue state. However, mean frequency showed compensating strategies in left leg muscles in response to fatigue. Conclusion: Hip stabilizers isometric pre-activation did not improve overall performance and coordination on jump squats. However, gluteus maximus and anterior tibialis showed a an improved fatigue resistance in non-dominant leg with pre-activation. Results from this study suggest that pre-activation protocols, while they produce no significant impact on performance, could be relevant for reducing lower-limb movement asymmetry during athlete training and as such, contribute to injury prevention and rehabilitation.

This study examined the impact of working memory deficits (WMD) on the academic achievement of adolescents with ADHD. Adolescents (n=79) aged 13 to 17 years with a clinical diagnosis of ADHD were subtyped into those with and without WMD based on impairment in at least two measures, and then compared on their academic achievement and clinical profile. Results indicated that adolescents with ADHD plus WMD (23%) manifest significantly lower academic achievement than those with adequate WM. By contrast, there were no group differences in psychiatric comorbidity, severity of ADHD symptoms and psychological adjustment. We also found a unique contribution of WM to academic achievement over and above that of other clinical features. These findings suggest that WMD compromise the educational attainment of a subgroup of individuals with ADHD. Individuals with ADHD should be screened for WMD to prevent academic failure and WM should be considered as a treatment target.

No description available.

Master of Science / Department of Family Studies and Human Services / Mark B. White / Although the processes by which fathers’ presence in the home affect children’s development is not known exactly, ongoing research is making strides toward a greater understanding of this concept (Lamb, 2000). Much of the research conducted on fathering came from researchers’ applying measures and concepts developed to understand mothering. This comparison of fathering and mothering has yielded little understanding of the processes by which father involvement can influence child development and, only in recent decades, has fathering begun to be studied using separate measures designed specifically to understand the unique aspects of fathering (Marsiglio, Amato, Day, & Lamb, 2001). To date, the effects of father involvement in families have been highlighted as a key factor in child growth and development, prevention of poverty, and as a buffer against adolescent risk-taking behaviors (Day & Lamb, 2004). However, in some cases, father involvement can have a very negative effect on children in families, and counter examples of research, showing the deleterious effects of negative father involvement, add an important aspect to fathering studies (Pleck, 2003). Unfortunately, the contradictory opinions and information found in research literature offer practitioners limited information upon which to base their work with fathers and their families. The following is a review of current research literature on father involvement, with an emphasis on families with adolescents. Recent improvements in researchers’ understanding and measurement of father involvement offer practical information for mental health practitioners. The written portion of this report will review current research on father involvement with adolescent children, and then in the presentation, offer suggestions for applying current fathering research to counseling practice. The goal of this report is to offer information that will narrow the research to practice gap for those working with adolescents and their families. Despite the flurry of research on father involvement in recent decades, little appears to have been done to make this research readily available to practitioners. Thus, current practices are limited, in that they are not benefiting from past research on father involvement and are not evolving with improved conceptualization and measurement of fathering activities. Given the current emphasis on evidence-based practice, this report is meant to be an added resource for practitioners, intending to help fathers in families with adolescents. In addition to a critical review of key works focusing on the effects of father involvement on adolescent children, this report will add insight to the work that clinicians do by discussing current perspectives in the fathering literature and offering suggestions for applying these ideas in the talk-therapy arena. Father influence on children during adolescence is the focus of this report due to research evidence showing that fathers influence may become increasingly important in the later stages of child development. (Amato, 1994; Faber, Edwards, Bauer, & Wetchler, 2003).

Doctor of Philosophy / Department of Family Studies and Human Services / Bronwyn S. Fees / When compared to adult mothers, adolescent mothers are more prone to parenting challenges (Whitman et al., 2001). Age is considered influential on a mother’s belief in her ability to successfully organize and execute her parenting plan (Bandura, 1999). The purpose of this study was to examine potential predictors of self-efficacy (determinant of parenting) among first-time mothers applying Belsky’s (1984) parenting framework. Maternal age, maternal depression, available social support and infant temperament were all considered to be potential predictors of maternal self-efficacy. A sample of first-time mothers (N = 115) with no other children in the home with an infant between the ages of four and six months was recruited from local alternative high schools, home and center child care facilities, and various other social services agencies and programs that typically serve new mothers. Participants self-reported on the above variables by completing a survey measuring self-efficacy as well as the hypothesized predictors. Responses were analyzed using group mean comparisons between 3 age groups: mothers 19 years and under (23%); mothers 20-26 years of age (29%); and mothers 26 years of age and older (48%). No significant differences in self-efficacy, perceived infant temperament, social support were found between age groups. Age differences in maternal depression fell just below significance. Maternal income level was significantly (and negatively) correlated with maternal depression, therefore was controlled for in additional analyses. Annual income, depression, and self efficacy were significantly correlated to perceived infant temperament. Mothers with lower incomes, who perceived less social support, who reported higher levels of depression, or had lower levels of self-efficacy were found to rate their infants as more temperamentally difficult. Regression analyses demonstrated that level of perceived social support significantly predicted maternal self-efficacy levels across all age groups. Additionally, infant temperament and maternal depression levels predicted self-efficacy. These findings provide evidence to support the importance of equal accessibility and affordability of social support for all new mothers to assist with the positive transition to parenthood.