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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Language Minority Children’s Sensitivity to the Semantic Relations Between Words

Unknown Date (has links)
The purpose of this study was to evaluate whether Spanish-speaking language minority children develop conceptual knowledge (Cummins, 1981) that is common to their two languages alongside development of proficiency in their first (L1) and second (L2) languages. Seventy-three first and second grade children completed two semantic priming tasks (i.e., a lexical decision task and a preferential looking paradigm) that were designed to examine children's sensitivity to the semantic relations between words within and across languages. It was hypothesized that within- and cross-language semantic priming effects would occur but that translation priming effects would not occur. Overall, results did not support hypotheses, as consistent semantic priming effects were not observed across the two tasks. However, limited evidence for semantic priming effects within English and from English to Spanish did emerge on the preferential looking paradigm. Substantial evidence for translation priming effects from Spanish-to-English was observed on the preferential looking paradigm. Children's Spanish vocabulary knowledge moderated translation priming effects on the lexical decision task. Although this pattern of results was not consistent with hypotheses, it was similar to the pattern of relations between bilingual individuals' L1 and L2 proposed by the revised hierarchical model (Kroll and Stewart, 1994). The results of this study indicated that Spanish-speaking language minority children rely on translation from their non-dominant to their dominant language to access meaning. Additionally, results provided limited evidence that information in the dominant and non-dominant language is activated simultaneously, indicating that children have conceptual knowledge that is common to both their L1 and L2. / A Dissertation submitted to the Department of Psychology in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Fall Semester 2015. / September 1, 2015. / language minority, semantic priming / Includes bibliographical references. / Christopher J. Lonigan, Professor Directing Dissertation; Carla Wood, University Representative; Arielle Borovsky, Committee Member; Michael Kaschak, Committee Member; Rick Wagner, Committee Member.
22

Increased Baseline YAP/TAZ Nuclear Localization and Responsiveness to Mechanical and Hormonal Changes Give Insight to Fibroid Pathophysiology

Purdy, MacKenzie Phyllice 06 April 2019 (has links)
<p> Uterine fibroids (UFs) are benign myometrial neoplasms that produce clinically-relevant symptoms in > 25% of all women and represent the leading cause of hysterectomy. Despite their importance, the mechanisms that promote UF growth are still not well-understood. Accumulating evidence indicates that the mechanical environment is altered and this may be a driver of fibroid pathobiology. There has been a proven regulatory mechanism for cellular proliferation with the Hippo pathway and the Yes-associated protein (YAP)/transcriptional coactivator with PDZ-binding domain (TAZ) in lung fibrosis which shares a response to gonadal steroids and serves as a model for this process. Here we assess the differences in YAP/TAZ nuclear localization and responsiveness to mechanical and hormonal cues in primary cells from UF compared to myometrium (Myo). Matched samples of UF and Myo were obtained from premenopausal women with IRB approval. Atomic force microscopy (AFM) was used to determine in-situ stiffness (N = 7). Immunohistochemistry (N = 5) was performed on OCT embedded tissue with YAP/TAZ antibody. For cell culture, UF and Myo were minced and digested with collagenase type 4. Cells (passages 1&ndash;4) were plated sparsely on hydrogels of five defined stiffness or at confluence on tissue culture plastic (N = 4 for both). Immunostaining for YAP/TAZ, Fibronectin (FN), Collagen I (COLI), and Collagen III (COLIII) were performed (N = 4&ndash;5). To perform siRNA, cells were incubated with control or YAP1 (YAP)/WWTR1 (TAZ) siRNA for 72 hours prior to analysis. RNA expression for Endothelin 1 (ET-1) and Connective Tissue Growth Factor (CTGF) was determined. Paired t-test and Wilcoxon sign-rank test were used as appropriate. AFM-measured stiffness was significantly higher in UF compared to Myo (p = 0.03). In freshly isolated cells cultured at confluence on tissue culture plastic, baseline YAP/TAZ nuclear localization was increased in UF when compared to Myo (p = 0.03). When seeded sparsely, decreasing substrate stiffness significantly (p = 0.05) reduced YAP/TAZ nuclear localization for both Myo and UF. Stimulation of confluent cells with 10nM estradiol and 100nM progesterone increased YAP/TAZ nuclear localization, but only in Myo (p = 0.01) as UF cells were constitutively active under these conditions. UFs also exhibited a trend toward increased FN, COLI, and COLIII deposition when compared to Myo. Following siRNA using YAP1 and WWTR1, ET-1 and CTGF were found to be statistically decreased which are known regulators of COLI and FN. These results demonstrate a possible feedback mechanism by which UFs progress by upregulation of matrix deposition, increase in tissue stiffness, and an increase in YAP/TAZ nuclear localization. </p><p>
23

Maternal Supportiveness of Infants at 1, 2, and 3 Years of Age in Low-Income Families: Associations With Maternal Characteristics, Child Characteristics, and Developmental Outcomes at 5 Years

Pressman, Aliza W. January 2011 (has links)
This study investigated maternal supportiveness of infants at 1, 2, and 3 years of age in low-income families. Maternal supportiveness over time was categorized as stably low, stably medium, stably high, increasing, or decreasing. The study determined associations between supportiveness group and (a) maternal characteristics, (b) child characteristics, and (c) child-development outcomes at age 5 years. The child-development outcomes were cognitive and social-emotional outcomes as measured by the Leiter-R, Peabody Picture Vocabulary Test-Third Edition, Woodcock-Johnson® III Tests of Achievement, Achenbach Child Behavior Checklist Aggressive Behavior subtest, and various measures from the Head Start Family and Child Experiences Survey. The study's data derived from the nationally representative Early Head Start Research and Evaluation Project, in which maternal supportiveness was assessed by means of observations of mother-infant play interactions. The current study's sample consisted of 1,019 mother-infant dyads. Findings differed from those of previous studies that investigated higher income, less ethnically diverse samples. Maternal-supportiveness groups significantly differed with respect to the child characteristic of emotion regulation and the following maternal characteristics: ethnicity, level of education, marital status, parenting stress, and knowledge of infant development. They also significantly differed with regard to the following child outcomes: sustained attention, receptive language, preliteracy, math skills, prosocial skills, and aggression. Stably high supportiveness was associated with the best cognitive and social-emotional outcomes, and stably low supportiveness was associated with the worst outcomes. Timing of maternal supportiveness was less predictive of child outcomes than level of maternal supportiveness, suggesting that mothers may benefit from intervention to improve supportiveness at any point during their child's first 3 years.
24

The Family Process Model: Predicting Youth Behavior Problems in Mexican American, African American, and European American Families

Barajas, Rita Gabriela January 2011 (has links)
Research in developmental psychology suggests that economic hardship affects youth indirectly via its negative impact on several family processes. Specifically, parents' mental well-being, family relations, and ultimately parenting, can be adversely affected by the strain of economic hardship and can lead to deleterious consequences on adolescent well-being. While considerable progress has been made in documenting whether these processes account for the adverse effects of economic hardship on family functioning in European American and African American families, less is known about the processes mediating the effects of economic hardship on Latino families. The lack of research on the applicability of the family process model to Latino families is surprising as Latinos are disproportionately affected by economic disadvantage. This study addresses these limitations in the literature by examining the applicability of the family process model to a large sample of Mexican heritage youth and families. Specifically, path models were used to test whether the family process model (where low income-to-needs ratio is negatively associated with maternal mental well-being and more family conflict, which are in turn associated with less warmth and more aggressive parenting, and ultimately child internalizing and externalizing behaviors) fit equally well across Mexican American, African American, and European American families. In addition, a test of the direct influence of family conflict on youth internalizing and externalizing behaviors was conducted. Further, this study examined whether lack of social support from families, lack of social support from friends, fear for safety, and discrimination helped explain the association between income and family conflict. Finally, this study considered whether neighborhood concentrated poverty, immigrant concentration, and residential stability helped explain the association between income-to-needs ratio and maternal mental stress. These questions were answered using data from 2,025 participants in the Project in Human Development in Chicago Neighborhoods (PHDCN). Specifically, information from 787 Mexican American, 881 African American, and 357 European American mothers and their children informed the findings of this study. The family process model fit equally well across first generation Mexican American, second generation Mexican American, African American, and European American households. Further, there was a positive direct association between family conflict and child internalizing and externalizing behaviors across all groups. Lack of social support from families, lack of social support from friends, fear for safety, and discrimination helped explain the association between income and family conflict across all groups. Inclusion of neighborhood characteristics did not fit the data well. We were thus unable to test whether neighborhood concentrated poverty, immigrant concentration, and residential stability helped explain the association between income-to-needs ratio and maternal mental stress.
25

Association of Maternal Cumulative Risk during Pregnancy and IQ in Preschoolers: Role of Glucocorticoids and their Receptors

Beckmann, Katherine January 2012 (has links)
There may be a cumulative effect of social and environmental risk factors which lead to chronic, elevated levels of stress. Constant elevations of maternal stress hormones during pregnancy disrupt developing fetal brain chemistry and architecture, resulting in later memory and learning deficiencies. While we know that the quality of the fetal environment and the timing of exposure to a variety of substances are critical for developmental and health outcomes, little is known about the consequences of maternal cumulative risk on the fetus and later cognitive development. With data from the Nurse Family Partnership Elmira Sample, this work investigates whether maternal cumulative risk during pregnancy predicts IQ in 3 and 4 year olds, without and with postnatal influences. The role that birth outcomes play as mediators of this relationship is also explored. Finally, moderation effects and cumulative genetic risk of five polymorphisms of the glucocorticoid receptor (GR) gene are examined. Increased maternal cumulative risk during pregnancy was negatively associated with IQ at ages 3 and 4 with and without the inclusion of postnatal controls. Birth outcomes partially mediated this relationship to a small extent. GR rs6198 G and rs6190 G alleles infer risk while rs6198 A alleles serve as protective factors with respect to the association of maternal cumulative risk during pregnancy and IQ in young children. This study contributes insights on the cumulative effects of chronic social and environmental stressors that may lead to increased levels of maternal stress hormones during pregnancy and poor cognitive outcomes in young children in the presence of specific glucocorticoid receptor single nucleotide polymorphisms. Application of findings to early intervention programming and policy is discussed.
26

Who's Who in Kindergarten Literacy Skill Groups: What Really Matters?

Mitchell, E. Imani January 2015 (has links)
American kindergartners enter schools with varying levels of emergent literacy skills. The present study examined the nature of variation of these skills through the lens of distinct literacy skill groups. Using the Early Childhood Longitudinal Study – Kindergarten (ECLS-K) data set, the literacy skill sets of over 10,000 children were examined at kindergarten and third grade. Latent class cluster analysis was used to demonstrate the presence of these groups through the analysis of proficiency probabilities of mastery of the following skills: 1) letter recognition; 2) beginning sound recognition; 3) ending sound recognition; 4) sight word recognition; 5) reading words in context; 6) literal inference; 7) extrapolation; and 8) evaluation. Three groups emerged for kindergarten based on skills 1-5, and three groups for third grade based on skills 4-8. Latent class multinomial logistic regression was used to examine the influence of contextual factors on determining group membership at both time points. Findings indicate that phonological awareness skills have the largest influence on determining literacy skill sets at kindergarten, most children enter kindergarten without mastery of the skills to be ready to learn to read, ethnicity does not have a significant effect once a comprehensive set of contextual factors (i.e., child, family, maternal, school, and family environment characteristics) are considered, and the family literacy environment has one of the strongest effects above and beyond the rest. By third grade, comprehension skills have the largest influence on determining skill sets. As for contextual factors, the patterns of influence appear to be lasting with consistency in group membership over time. Taken together these results have the potential implications supporting parents throughout the nation.
27

Low Alcohol Consumption: Maternal Functioning and offspring Development

Herrman, Jana J. 01 January 1984 (has links)
No description available.
28

Impact of reduced calcium during development in snakes

Mathis, Kaitlyn A 01 May 2016 (has links)
In squamate reptiles, the evolutionary transition from oviparity to viviparity is accompanied by loss of the calcareous outer eggshell, which suggests significant implications for the role of calcium during embryonic development (Packard et al., 1977). An experiment was designed to evaluate the impact of reduced calcium availability during development in the oviparous corn snake, Pantherophis guttatus (Stewart and Ecay, 2013). Results from that study showed significant decreases in the mass and length of hatchling corn snakes when the outer calcareous eggshell layer was removed during development. In vertebrates, variation in total body length reflects skeletal differences---primarily differences in the number or sizes of vertebrae and/or differences in length of the skull. Skeletal components obviously are affected by the availability of calcium during development. My study was designed to determine the anatomical and developmental bases for the smaller size observed in hatchling snakes subjected to reduction of eggshell calcium during embryonic development. My hypotheses were, as follows: 1) Differences in mass reflected differences in overall length of hatchlings; 2) Differences in length resulted from decreased size of vertebrae---rather than decreased number---and/or decreased length of skulls in hatchlings with reduced calcium. Hatchlings were prepared for skeletal analysis via clearing-and-staining. Vertebrae of each hatchling were counted and size measurements obtained for separate spinal regions (cervical, thoracic, and caudal). Results demonstrate a significant treatment effect on size of vertebrae in the thoracic and anterior caudal regions, as well as length of the skull. These findings suggest that reduced developmental calcium, comparable to the condition in viviparous species, impacts ossification and growth of skeletal elements in late development.
29

An Ultrastructure Study of Strobilation in Chrysaora quinquecirrha with Special Reference to Neurosecretion

Dietz, Marsha Ann 01 January 1971 (has links)
No description available.
30

Psychological development of infants conceived through in vitro fertilization

Van de Water, Virginia Lee 01 January 1988 (has links)
In 1984, The National Institute of Child Health and Human Development awarded a grant to The Eastern Virginia Medical School and The Children's Hospital of The King's Daughters to study the IVF children conceived a The Jones Institute for Reproductive Medicine in Norfolk, Virginia. The purpose of the study was to assess the children comprehensively using a multi-disciplinary team to determine whether the IVF process resulted in higher than average physical and/or behavioral deficits. The children were psychologically tested on the Bayley Scales of Infant Development; they also received pediatric, neurological, cardiac, and ultrasound examinations of their internal organs. 83 of 105 eligible IVF children were examined. These children were matched on the following criteria: maternal age, child's age, race, gender, births/pregnancy, and socioeconomic status. The controls were obtained from a 100 mile radius of Norfolk, Virginia. Ninety-three children served as controls. All were between 12 and 30 months of age.;The results indicate that these families are different from the general population in several respects: they are older, better educated, more affluent, almost all white, and have a higher rate of multiple births. The groups did not differ in their rate of congenital defects. While prematurity was common, the children demonstrated no adverse effects from their prematurity.;The psychological results indicated that both groups were above the national norms for the Bayley Scales on both their MDIs and PDIs; they did not differ significantly, but the IVF group was higher on both scores. Two IVF children with physical handicaps were cognitively normal. Behaviorally the groups did not differ at the p =.01 level on any of the Behavioral Record variables.;The NICHHD study concludes that the risk of the IVF process is acceptable from a medical viewpoint. The children who are born do not demonstrate a higher rate of physical or psychological abnormalities based on current information.

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