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Description
Ethnic identity has consistently been associated with Latino youths' psychosocial well-being; however, an area that has received much less attention is how parents' characteristics inform their ethnic socialization efforts and, in turn, youths' ethnic identity. In addition, we know little about how this process unfolds in specific at-risk samples of youth, such as adolescent mothers. Thus, the current prospective study examined how mothers' cultural characteristics informed adolescents' and mothers' reports of ethnic socialization, and how this, in turn, informed adolescents' ethnic identity exploration and resolution among a sample of 193 adolescent mothers and their mothers. In addition, the current study tested whether mothers' ethnic identity affirmation was directly related to adolescents' ethnic identity affirmation over time. Results indicated that mothers' familism was associated with increases in mothers' reports of maternal ethnic socialization, and, in turn, with increases in ethnic identity exploration for foreign-born adolescents, and decreases in ethnic identity exploration for U.S.-born adolescents. In addition, adolescents' reports of familial ethnic socialization were associated with increases in their ethnic identity exploration and resolution. Finally, mothers' ethnic identity affirmation was associated with increases in adolescents' ethnic identity affirmation. Findings are discussed with special attention to the importance of mothers' cultural values in how they socialize their adolescents, and this impact on adolescents' ethnic identity, as well as the implications this study has for interventions focused on bolstering positive outcomes for adolescent mothers.
ContributorsDerlan, Chelsea L (Author) / Umaña-Taylor, Adriana J. (Thesis advisor) / Knight, George P. (Committee member) / Updegraff, Kimberly A. (Committee member) / Arizona State University (Publisher)
Created2012
Description
In somatic cells, the mitotic spindle apparatus is centrosomal and several isoforms of Protein Kinase C (PKC) have been associated with the mitotic spindle, but their role in stabilizing the mitotic spindle is unclear. Other protein kinases such as, Glycogen Synthase Kinase 3â (GSK3â) also have been shown to be associated with the mitotic spindle. In the study in chapter 2, we show the enrichment of active (phosphorylated) PKCæ at the centrosomal region of the spindle apparatus in metaphase stage of 3T3 cells. In order to understand whether the two kinases, PKC and GSK3â are associated with the mitotic spindle, first, the co-localization and close molecular proximity of PKC isoforms with GSK3â was studied in metaphase cells. Second, the involvement of inactive GSK3â in maintaining an intact mitotic spindle was shown. Third, this study showed that addition of a phospho-PKCæ specific inhibitor to cells can disrupt the mitotic spindle microtubules. The mitotic spindle at metaphase in mouse fibroblasts appears to be maintained by PKCæ acting through GSK3â. The MAPK pathway has been implicated in various functions related to cell cycle regulation. MAPKK (MEK) is part of this pathway and the extracellular regulated kinase (ERK) is its known downstream target. GSK3â and PKCæ also have been implicated in cell cycle regulation. In the study in chapter 3, we tested the effects of inhibiting MEK on the activities of ERK, GSK3â, PKCæ, and á-tubulin. Results from this study indicate that inhibition of MEK did not inhibit GSK3â and PKCæ enrichment at the centrosomes. However, the mitotic spindle showed a reduction in the pixel intensity of microtubules and also a reduction in the number of cells in each of the M-phase stages. A peptide activation inhibitor of ERK was also used. Our results indicated a decrease in mitotic spindle microtubules and an absence of cells in most of the M-phase stages. GSK3â and PKCæ enrichment were however not inhibited at the centrosomes. Taken together, the kinases GSK3â and PKCæ may not function as a part of the MAPK pathway to regulate the mitotic spindle.
ContributorsChakravadhanula, Madhavi (Author) / Capco, David G. (Thesis advisor) / Chandler, Douglas (Committee member) / Clark-Curtiss, Josephine (Committee member) / Newfeld, Stuart (Committee member) / Arizona State University (Publisher)
Created2012
Description
Cognitive function declines with normal age and disease states, such as Alzheimer's disease (AD). Loss of ovarian hormones at menopause has been shown to exacerbate age-related memory decline and may be related to the increased risk of AD in women versus men. Some studies show that hormone therapy (HT) can have beneficial effects on cognition in normal aging and AD, but increasing evidence suggests that the most commonly used HT formulation is not ideal. Work in this dissertation used the surgically menopausal rat to evaluate the cognitive effects and mechanisms of progestogens proscribed to women. I also translated these questions to the clinic, evaluating whether history of HT use impacts hippocampal and entorhinal cortex volumes assessed via imaging, and cognition, in menopausal women. Further, this dissertation investigates how sex impacts responsiveness to dietary interventions in a mouse model of AD. Results indicate that the most commonly used progestogen component of HT, medroxyprogesterone acetate (MPA), impairs cognition in the middle-aged and aged surgically menopausal rat. Further, MPA is the sole hormone component of the contraceptive Depo Provera, and my research indicates that MPA administered to young-adult rats leads to long lasting cognitive impairments, evident at middle age. Natural progesterone has been gaining increasing popularity as an alternate option to MPA for HT; however, my findings suggest that progesterone also impairs cognition in the middle-aged and aged surgically menopausal rat, and that the mechanism may be through increased GABAergic activation. This dissertation identified two less commonly used progestogens, norethindrone acetate and levonorgestrel, as potential HTs that could improve cognition in the surgically menopausal rat. Parameters guiding divergent effects on cognition were discovered. In women, prior HT use was associated with larger hippocampal and entorhinal cortex volumes, as well as a modest verbal memory enhancement. Finally, in a model of AD, sex impacts responsiveness to a dietary cognitive intervention, with benefits seen in male, but not female, transgenic mice. These findings have clinical implications, especially since women are at higher risk for AD diagnosis. Together, it is my hope that this information adds to the overarching goal of optimizing cognitive aging in women.
ContributorsBraden, Brittany Blair (Author) / Bimonte-Nelson, Heather A. (Thesis advisor) / Neisewander, Janet L (Committee member) / Conrad, Cheryl D. (Committee member) / Baxter, Leslie C (Committee member) / Arizona State University (Publisher)
Created2012
Description
The use of bias indicators in psychological measurement has been contentious, with some researchers questioning whether they actually suppress or moderate the ability of substantive psychological indictors to discriminate (McGrath, Mitchell, Kim, & Hough, 2010). Bias indicators on the MMPI-2-RF (F-r, Fs, FBS-r, K-r, and L-r) were tested for suppression or moderation of the ability of the RC1 and NUC scales to discriminate between Epileptic Seizures (ES) and Non-epileptic Seizures (NES, a conversion disorder that is often misdiagnosed as ES). RC1 and NUC had previously been found to be the best scales on the MMPI-2-RF to differentiate between ES and NES, with optimal cut scores occurring at a cut score of 65 for RC1 (classification rate of 68%) and 85 for NUC (classification rate of 64%; Locke et al., 2010). The MMPI-2-RF was completed by 429 inpatients on the Epilepsy Monitoring Unit (EMU) at the Scottsdale Mayo Clinic Hospital, all of whom had confirmed diagnoses of ES or NES. Moderated logistic regression was used to test for moderation and logistic regression was used to test for suppression. Classification rates of RC1 and NUC were calculated at different bias level indicators to evaluate clinical utility for diagnosticians. No moderation was found. Suppression was found for F-r, Fs, K-r, and L-r with RC1, and for all variables with NUC. For F-r and Fs, the optimal RC1 and NUC cut scores increased at higher levels of bias, but tended to decrease at higher levels of K-r, L-r, and FBS-r. K-r provided the greatest suppression for RC1, as well as the greatest increases in classification rates at optimal cut scores, given different levels of bias. It was concluded that, consistent with expectations, taking account of bias indicator suppression on the MMPI-2-RF can improve discrimination of ES and NES. At higher levels of negative impression management, higher cut scores on substantive scales are needed to attain optimal discrimination, whereas at higher levels of positive impression management and FBS-r, lower cut scores are needed. Using these new cut scores resulted in modest improvements in accuracy in discrimination. These findings are consistent with prior research in showing the efficacy of bias indicators, and extend the findings to a psycho-medical context.
ContributorsWershba, Rebecca E (Author) / Lanyon, Richard I (Thesis advisor) / Barrera, Manuel (Committee member) / Karoly, Paul (Committee member) / Millsap, Roger E (Committee member) / Arizona State University (Publisher)
Created2013
Description
Recommendations made by expert groups are pervasive throughout various life domains. Yet not all recommendations--or expert groups--are equally persuasive. This research aims to identify factors that influence the persuasiveness of recommendations. More specifically, this study examined the effects of decisional cohesion (the amount of agreement among the experts in support of the recommendation), framing (whether the message is framed as a loss or gain), and the domain of the recommendation (health vs. financial) on the persuasiveness of the recommendation. The participants consisted of 1,981 undergraduates from Arizona State University. The participants read a vignette including information about the expert group making a recommendation--which varied the amount of expert agreement for the recommendation--and the recommendation, which was framed as either a gain or loss. Participants then responded to questions about the persuasiveness of the recommendation. In this study, there was a linear main effect of decisional cohesion such that the greater the decisional cohesion of the expert group the more persuasive their recommendation. In addition, there was a main effect of domain such that the health recommendation was more persuasive than the financial recommendation. Contrary to predictions, there was no observed interaction between the amount of decisional cohesion and the framing of the recommendation nor was there a main effect of framing. Further analyses show support for a mediation effect indicating that high levels of decisional cohesion increased the perceived entitativity of the expert group--the degree to which the group was perceived as a unified, cohesive group¬--which increased the recommendation's persuasiveness. An implication of this research is that policy makers could increase the persuasiveness of their recommendations by promoting recommendations that are unanimously supported by their experts or at least show higher levels of decisional cohesion.
ContributorsVotruba, Ashley M (Author) / Kwan, Virginia S.Y. (Thesis advisor) / Saks, Michael J. (Committee member) / Demaine, Linda (Committee member) / Arizona State University (Publisher)
Created2013
Description
Although aggression is sometimes thought to be maladaptive, evolutionary theories of resource control and dominance posit that aggression may be used to gain and maintain high social prominence within the peer group. The success of using aggression to increase social prominence may depend on the form of aggression used (relational versus physical), the gender of the aggressor, and the prominence of the victim. Thus, the current study examined the associations between aggression and victimization and social prominence. In addition, the current study extended previous research by examining multiple forms of aggression and victimization and conceptualizing and measuring social prominence using social network analysis. Participants were 339 6th grade students from ethnically diverse backgrounds (50.4% girls). Participants completed a peer nomination measure assessing relational and physical aggression and victimization. They also nominated friends within their grade, which were used to calculate three indices of social prominence, using social network analysis. As expected, results indicated that relational aggression was associated with higher social prominence, particularly for girls, whereas physical aggression was less robustly associated with social prominence. Results for victimization were less clear, but suggested that, for girls, those at mid-levels of social prominence were most highly victimized. For boys, results indicated that those both high and low in prominence were most highly relationally victimized, and those at mid-levels of prominence were most highly physically victimized. These findings help inform intervention work focused on decreasing overall levels of aggressive behavior.
ContributorsAndrews, Naomi C. Z (Author) / Hanish, Laura D. (Thesis advisor) / Martin, Carol Lynn (Committee member) / Updegraff, Kimberly A (Committee member) / Arizona State University (Publisher)
Created2013
Description
Approximately one-third of Iraq and Afghanistan veterans develop mental health problems, yet only 35-40% of those with mental disorders are seeking mental healthcare (Hoge, et al., 2004; Vogt, 2011). Military spouses may be an important resource for facilitating treatment seeking (Warner, et al., 2008), especially if service member mental health issues are impacting the marriage. Military spouses might be hesitant to encourage service member help-seeking, however, due to perceived threat of adverse military career consequences. For this study, 62 military wives completed an online survey. As part of the survey, participants were randomly assigned to one of four vignettes containing a description of a hypothetical military husband with mental health symptoms. Each vignette presented different combinations of marital conflict (high versus low) and service member concerns about adverse career consequences (high versus low). Wives rated on a five-point scale how likely they were to encourage the hypothetical military husband to seek help. It was hypothesized that spouses would be more willing to encourage help-seeking when concerns about adverse military career consequences were low and marital distress was high. No main effects or interaction effect were found for marriage and career. Perceived stigma about seeking mental health treatment in the military, psychological identification as a military spouse, and experience and familiarity with military mental healthcare policies failed to moderate the relationship between marital conflict, career concerns, and encouragement of help-seeking. Correlational analyses revealed that (1) greater experience with military mental healthcare (first- or secondhand), and (2) greater perceptions of stigma regarding seeking mental healthcare in the military each were associated with decreased perceptions of military supportiveness of mental healthcare. Therefore, although the experimental manipulation in this study did not lead to differences in military spouses' encouragement of a hypothetical military service member to seek mental health services, other findings based on participants' actual experiences suggest that experiences with military mental healthcare may generate or reinforce negative perceptions of military mental healthcare. Altering actual experiences with military mental healthcare, in addition to perceptions of stigma, may be a useful area of intervention for military service members and spouses.
ContributorsHermosillo, Lori (Author) / Roberts, Nicole (Thesis advisor) / Burleson, Mary (Committee member) / Tinsley, Barbara (Committee member) / Arizona State University (Publisher)
Created2013
Description
Time adolescents spend in organized or informal skill based activities after school is associated with a variety of positive developmental outcomes. Little is known about how siblings might shape adolescents' motivation to participate in after-school activities. The current study applied the expectancy value model and ecological theory to understand if sibling behaviors were related to adolescents' after-school activities for 34 Mexican origin families. Qualitative and quantitative results suggested siblings engaged in five promoting behaviors (i.e., support, provider of information, role modeling, comparison, co-participation) and three inhibiting behaviors (i.e., babysitting, transportation, and negativity) towards adolescent activity participation. Furthermore, sibling behaviors differed by adolescent characteristics (i.e., cultural orientation, familism, and neighborhood) and sibling characteristics (i.e., gender, age). The results provide evidence of the various promoting and inhibiting socialization behaviors sibling might use to influence adolescents' activity motivation.
ContributorsPrice, Chara Dale (Author) / Simpkins, Sandra (Thesis advisor) / Updegraff, Kimberly (Committee member) / Menjivar, Cecilia (Committee member) / Arizona State University (Publisher)
Created2012
Description
The hypothalamus pituitary adrenal (HPA) axis and the human genome are important components of the biological etiology of externalizing disorders. By studying the associations between specific genetic variants, diurnal cortisol, and externalizing symptoms we can begin to unpack this complex etiology. It was hypothesized that genetic variants from the corticotropine releasing hormone receptor 1 (CRHR1), FK506 binding protein 51 (FKBP5), catechol-O-methyl transferase (COMT), and dopamine transporter (DAT1) genes and diurnal cortisol intercepts and slopes would separately predict externalizing symptoms. It was also hypothesized that genetic variants would moderate the association between cortisol and externalizing. Participants were 800 twins (51% boys), 88.5% Caucasian, M=7.93 years (SD=0.87) participating in the Wisconsin Twin Project. Hierarchical Linear Modeling (HLM) was used to separate the variance associated with state and trait cortisol measured across three consecutive days and trait cortisol measures were used. There were no main effects of genes on externalizing symptoms. The evening cortisol intercept, the morning cortisol slope and the evening cortisol slope predicted externalizing, but only in boys, such that boys with higher cortisol and flatter slopes across the day also had more externalizing symptoms. The morning cortisol intercept and CRHR1 rs242924 interacted to predict externalizing in both boys and girls, with GG carriers significantly higher compared to TT carriers at one standard deviation below the mean of morning cortisol. For boys only there was a significant interaction between the DAT1 variable number tandem repeat (VNTR) and the afternoon slope and a significant slope for 9/9 carriers and 9/10 carriers such that when the slope was more steep, boys carrying a nine had fewer externalizing symptoms but when the slope was less steep, they had more. Results confirm a link between diurnal trait cortisol and externalizing in boys, as well as moderation of that association by genetic polymorphisms. This is the first study to empirically examine this association and should encourage further research on the biological etiology of externalizing disorder symptoms.
ContributorsSwann, Gregory (Author) / Lemery-Chalfant, Kathryn (Thesis advisor) / Chassin, Laurie (Committee member) / Doane-Sampey, Leah (Committee member) / Arizona State University (Publisher)
Created2012
Description
Infertility has become an increasing problem in developed countries and in many cases can be attributed to compromised sperm quality. Assessment of male fertility typically utilizes semen analysis which mainly examines sperm morphology, however many males whose sperm appear normal are sub- or infertile, suggesting that sperm from these males may be deficient in a protein or suite of proteins. To date, very little is known about the composition of sperm or the complex maturation process that confers motility and fertilization competency to sperm. Chapter 1 discusses the use of whole cell mass spectrometry to identify 1247 proteins comprising the Rhesus macaque (Macaca mulatta) sperm proteome, a commonly used model of human reproduction. This study provides a more robust proxy of human sperm composition than was previously available and facilitates studies of sperm using the rhesus macaque as a model. Chapters 2 & 3 provide a systems level overview of changes in sperm proteome composition that occurs during epididymal transit. Chapter 2 reports the proteomes of sperm collected from the caput, corpus and cauda segments of the mouse epididymis, identifying 1536, 1720 and 1234 proteins respectively. Chapter 3 reports the sperm proteome from four distinct segments of the Rhesus macaque epididymis, including the caput, proximal corpus, distal corpus and cauda, identifying 1951, 2014, 1764 and 1423 proteins respectively. These studies identify a number of proteins that are added and removed from sperm during epididymal transit which likely play an important role in the sperm maturation process. To date no comparative evolutionary studies of sperm proteomes have been undertaken. Chapter 4 compares four mammalian sperm proteomes including the human, macaque, mouse and rat. This study identified 98 proteins common to all four sperm proteomes, 82 primate and 90 rodent lineage-specific proteins and 494, 467, 566, and 193 species specific proteins in the human, macaque, mouse and rat sperm proteomes respectively and discusses how differences in sperm composition may ultimately lead to functional differences across species. Finally, chapter 5 uses sperm proteome data to inform the preliminary design of a rodent contraceptive vaccine delivered orally using recombinant attenuated Salmonella vaccine vectors.
ContributorsSkerget, Sheri Jo (Author) / Karr, Timothy L. (Thesis advisor) / Lake, Douglas (Committee member) / Petritis, Konstantinos (Committee member) / Arizona State University (Publisher)
Created2013