cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.25549/usctheses-c40-351038
title: Analysis of the American Board of Orthodontics Model Grading System: plaster versus digital models

description: Introduction: The American Board of Orthodontics (ABO) developed the Model Grading System to enhance the reliability of examiners and to provide the examinees the tools to assess the adequacy of their finished orthodontic results. In recent years, the ABO has begun to accept pre- and post-treatment models in digital format. The purpose of this study is to determine if there are statistical differences between plaster and digital orthodontic models in scoring the ABO Model Grading System. Methods: 12 post-treatment plaster orthodontic study models were selected based on the criteria that each have been submitted to the ABO clinical exam and passed with a score between 10-30. The study models were scanned and oriented using Motion View Ortho Insight 3D, version 6.5.5046, to produce 12 corresponding digital models. 12 orthodontic residents graded the plaster and digital models using the ABO Model Grading System. Digital models were graded using the ABO Model Conversion Utility software (Motion View, Chattanooga, TN), version 6.7.24. The variables evaluated include alignment, marginal ridge, buccolingual inclination, occlusal contacts, occlusal relationship, overjet, and interproximal contacts. All data was entered for statistical analysis to assess examiner reliability and differences between grading plaster and digital models. Results: Buccolingual inclination and overjet were statistically significant when comparing digital and plaster models. High intraclass correlation coefficient of reliability for the 2 examiners that repeated the grading for all 12 plaster and digital models demonstrates agreement for all variables and total score when done by the same examiner. The reliability for digital models was also higher than plaster models for both examiners. Interexaminer reliability was excellent in all 7 categories with digital models demonstrating slightly higher reliability than plaster models. Conclusions: Based on this study, the current ABO Model Conversion Utility software was not adequate for scoring all the criterion of the ABO Model Grading System, and adequate calibration of the examiners is essential to achieve repeatability in both plaster and digital methods.
DOI: 10.25549/usctheses-c40-351964
title: Application of time series analysis and machine learning on stock forecasting

description: In modern financial analysis, price forecasting is very important. There are two main schools of idea to do analyzing. One is based on the news and event published regarding the target company’s stock price. In this article, I will use the data from Google Trend and Yahoo Finance to come up a news and event index that indicates the future weekly price change. The other one is numerical analysis. The Time Series Analysis is one of the most popular ways to do numerical analysis, I will fit the past five-year weekly stock price change of a target company into a couple of time series model and analyzing the linear trend of it. The goal of this research is to try to build a model that combines these two facts (news and event index and time series prediction) together and to make our prediction more precise.
DOI: 10.25549/usctheses-c127-624566
title: Addressing the high school dropout crisis: at-risk students and education2020 online credit recovery

description: The purpose of this study was to examine at-risk students’ satisfaction with an online credit recovery program, education2020, and its potential for providing equal opportunities to get students back on track toward graduation. This study also determined the degree to which at-risk student characteristics such as socioeconomic status, gender, age, ethnicity, and academic behaviors affected experiences in education2020 as measured by student satisfaction and pace of credit recovery. ❧ This study consisted of 220 high school students enrolled in the education2020 online credit recovery program at a small, urban high school district. Students came from three comprehensive high schools and one continuation school. The sample included students who were identified for education2020 due to applicable credit deficiency. A district-initiated survey gathered all demographic information and satisfaction levels. De-identified credit recovery data from one quarter revealed credit recovery patterns of one group of 67 seniors from the original 220-student sample. The survey data was analyzed using a hierarchical linear regression analysis to determine whether any student characteristics predicted satisfaction with education2020. Credit recovery data was examined using anova and Chi-square analyses to determine the relationship between pace of recovery and specific variables such as school site, academic behaviors, age, and ethnicity. ❧ The results of this study indicated that no demographic characteristic predicted satisfaction with education2020; the only significant variance was related to school site. There was no significant relationship between demographic characteristics and pace of credit recovery, but there was a positive correlation between academic behaviors such as prior credits earned and pass rate in concurrent face-to-face classes. ❧ Because no demographic characteristic prevented or ensured success in e2020, these findings demonstrate equal opportunity for at-risk students to find satisfaction and to recover credits. However, learning environment factors and academic behaviors did, in fact, demonstrate a relationship to satisfaction and pace of credit recovery. This information suggests that further research is needed to examine the specific components of the online learning environment and of programs for at-risk students, as well as their success in concurrent face-to-face classes and ability to recover credits in an online credit recovery program.
DOI: 10.25549/usctheses-c127-638027
title: The relationship between the implementation of a differentiated curriculum and the development of intellectualism

description: This study was conducted to explore the perceptions of gifted students and their teachers on the relationship between the implementation of a differentiated curriculum designed to meet the needs of gifted students and the development of intellectualism. In this mixed methods study data was gathered using an online teacher survey, teacher interviews, student focus groups, and a document analysis of the descriptions of five widely implemented programmatic and curricular models. The results indicated that both gifted students and their teachers perceive the development of intellectualism to be congruent with the purposes and outcomes of a differentiated curriculum as defined by the GATE Standards, California Department of Education (2005). Impediments to the development of intellectualism identified by the students and teachers included a prescribed curriculum, the structure of the school day, excessive testing, untrained principals, and student goal orientation. ❧ The analysis of the programmatic and curricular models indicated that the structure of each model was congruent with the development of intellectualism. However, an analysis of the descriptions of a differentiated curriculum and the mission statements of schools and districts currently implementing each model indicated inconsistencies between the immediate and long-term goals of the schools and districts as they related to the development of intellectualism. The results of this study implied that professional development opportunities for teachers and principals need to include intellectual challenge and that efforts need to be made to develop a mastery goal orientation for gifted students
DOI: 10.25549/usctheses-c127-649206
title: Los jardineros de Los Angeles: suburban maintenance gardening as a pathway to first and second generation Mexican immigrant mobility

description: This dissertation is the first in-depth study of the Mexican immigrant men who work as suburban maintenance gardeners throughout Los Angeles.  Specifically, it is an interview-based study of social mobility among first-generation Mexican immigrant gardeners, or jardineros, and among their U.S.-born young adult children.  In it, I ask several key questions, including: Is there a false distinction between entrepreneurship and manual labor?  And what can account for the remarkable degree of social mobility that some Mexican immigrant gardeners and their young adult children can experience?  After reviewing of the history of this immigrant occupational niche in Los Angeles, I find that self-employed jardineros can earn relatively high incomes through their maintenance gardening routes.  The profitability of their routes rests upon several key factors, including: (1) self-exploitation; (2) the exploitation of co-ethnic employees; (3) the exploitation of unpaid family labor; (4) the routine practice of taking on “extra” jobs; and (5) the reselling of plants and other garden materials to clients at marked-up prices.  Meanwhile, some of the factors that contribute to the social mobility of the children of jardineros include: (1) work ethic lessons; (2) the positive mechanism of keeping kids occupied with gardening work or under close supervision; (3) fathers’ social capital and know-how; (4) being able to afford good schools; and (5) homeownership.  The findings of this study challenge taken-for-granted notions about the fate of Mexican immigrant workers with low levels of human capital as well as the fate of their U.S.-born young adult children.  Moreover, the suburban maintenance gardening niche combines elements of ethnic entrepreneurship and subjugated service work in a way that has not been accounted for in the literature on immigrant entrepreneurs.
DOI: 10.25549/usctheses-c127-655638
title: The effects of ascorbates on Cr(VI)-induced cytotoxicity in C3H 10T1/2 mouse cells

description: Compounds containing hexavalent chromium [Cr(VI)] are well-documented human carcinogens that cause cancers in the respiratory system, including the lungs. In this paper, we examined the ability of the insoluble Cr(VI) compound, lead chromate, PbCrO4, to induce morphological transformation of C3H 10T1/2 mouse embryonic fibroblastic cells. We seeded the cells at 2,000 cells per 60mm dish, then treated the cells 1 day after seeding with PbCrO4 at three concentrations, 1.72μg/mL, 2.5μg/mL, and 4.21μg/mL. Next, we also followed the Nesnow protocol where we seeded 2,000 cells per 60 mm dish, and then treated the cells on Day 5 after they were seeded, for 48 hours. Interestingly, we found very low induction of morphologically transformed foci induced by PbCrO4 when compared with the high yields of foci induced by 1μg/mL of 3-methylcholanthrene ( MCA). This is surprising considering that Cr(VI) compounds are strong human carcinogens to the respiratory system. However we realized from reading the scientific literature, that ascorbate, a dominant biological reducing agent, is required for reductive activation of the carcinogenic activity of Cr(VI). In addition, we realized that Cr(VI) is usually present in the micromolar range when humans are exposed to it occupationally, whereas by contrast ascorbate is present at concentrations in the millimolar range under physiological conditions in humans. Therefore we investigated the cytotoxic effects of ascorbate on 10T1/2 mouse embryo cells, and the effect of ascorbate on Cr(VI)-induced cytotoxicity in 10T1/2 cells. Our preliminary cell survival data revealed that ascorbate can itself exert a cytotoxic effect on the 10T1/2 mouse embryo cells. Furthermore when 10T1/2 cells were treated with both Cr(VI) and ascorbate, we found that ascorbate played dual roles. It serves as an anti-oxidant as well as a pro-oxidant. We also found that treating the cells with &lt;0.07mM, caused only minimal or no cytotoxicity, and also showed that ascorbate at this concentration had a pro-oxidative activity, i.e. ascorbate reduced the cytotoxicity of Cr(VI) to 10T1/2 cell. This information could be crucial when we design a protocol to incorporate ascorbate into our transformation assay.
DOI: 10.25549/usctheses-c127-670412
title: Management systems and policies, their effect on compliance with safety regulations and safety outcomes: a case study of an electrical utility company

description: This research is explores how organizational systems influence its members' ability to meet regulatory and safety compliance.  The contribution of systems theory is important in today's world where organizations must comply with mandated and negotiated regulatory requirements for licensing, funding, and other purposes such as performance objectives. ❧ The literature on safety climate and safety culture has defined a variety of dimensions which contribute to the overall safety climate of an organization by assessing employee perceptions about these dimensions.  The definitions used to describe these dimensions, however, are unclear and overlap.  Thus they do not provide useful information about how to implement a good safety program or what dimensions would overlap across different industries to achieve safety compliance. ❧ This study uses data from open-ended interviews which were collected during a consulting project which was undertaken because of a failure in this organization's systems to accurately report compliance and safety compliance.  The data was derived by coding the interview comments to the safety climate and safety culture dimensions.  A number of themes which were not addressed in the literature emerged from the analysis of the comments. The data and comments were used to explore the meaning and function of the safety climate and safety culture dimensions in the organization.  Where independent themes arose, these were also explored. ❧ The findings of this study suggest that organizations would benefit from using a systems approach to design their compliance and safety compliance programs.  Rather than using the dimensions found in the safety climate and safety culture to design a compliance program, the findings from this study suggest that a systems approach for compliance programs would create a high-performing safety program.  Such a program would be comprised of organizational policies, support systems, and practices, aligned to work together, and using audits and controls to check if the system is working as it should.
DOI: 10.25549/usctheses-c127-671859
title: Reducing the risk among the most at-risk: determining what contributes to African-American males in special education having the highest rates of incarceration and academic failure

description: Large disparities exist in the dropout and incarceration rates of different races, genders, and disabilities. These two phenomena, commonly referred to as the Achievement Gap and Incarceration Gap, also contribute to other problems within society and cost taxpayers billions of dollars annually. Because of the intersection of race, gender, and disability, African-American males in special education have both the highest dropout and incarceration rates. However, few studies have focused on this specific subgroup and the factors contributing to their significantly lower outcomes. The purpose of this study is to examine the differences between successful and unsuccessful African-American males in special education at a Los Angeles High School. Specifically, it will compare high-achieving and non-delinquent African-American males in special education to their low-achieving and delinquent counterparts. This comparison will be done across various environmental and personal (psychological) factors in an effort to explain what contributes to the high dropout and incarceration rates among the population. A total of fifteen environmental factors across the home, community, and school environments were explored. The psychological constructs of self-efficacy and school engagement were explored as personal factors. Data were collected utilizing a mixed-method approach with quantitative surveys and qualitative focus groups. Quantitatively, chi-square tests were used to compare frequencies across environmental factors while t-tests were used to compare student means across personal factors. Qualitative data was organized into themes and reported with its corresponding research questions. A total of 31 students completed surveys and 16 students participated in focus groups. All participants were between the ages of 14 through 19. Findings indicate  significant differences across both the environment and personal factors of successful and unsuccessful African-American males in special education exist. Findings also indicate more significant differences exist between non-delinquent and delinquent students than high and low achieving students. Based on these findings, several changes may be implemented to reduce dropout and incarceration rates among this most vulnerable group.
DOI: 10.25549/usctheses-c40-120314
title: The Continuing Education in Social Work Project: An evaluation
DOI: 10.25549/usctheses-c40-317060
title: The impact of preschool interactions on the development of language and reasoning skills

description: This study applies Vygotsky’s social development theory and previous findings on teacher-child interactions to understanding environmental factors in the classroom environment that increase expressive language and reasoning skills in preschool children. The purpose of this study was to identify specific factors in the classroom environment, specifically emotional climate, classroom organization, and instructional support that is related to higher expressive language and reasoning skills in preschool children. This study used teacher interviews and standardized observations (Classroom Assessment Scoring System) to obtain ratings of classroom quality in the areas of emotional climate, classroom organization, and instructional support in four classrooms at a private religious school. A total of 16 students who had attended each preschool class the year prior were administered the TELD-3, and play-based reasoning tasks. Parents completed a Home Environment Survey on learning experiences, developmental information, and parent factors. The amount of time parents spent reading to children and parent’s first language were statistically and significantly correlated with performance on reasoning tasks. Screen time was correlated with lower performance on reasoning tasks. As found in several other studies (Bracken & Fischel, 2008; Mashburn & Pianta, 2006) findings indicate that parents must be encouraged to read to their children, and continue to limit screen time.
DOI: 10.25549/usctheses-c127-623166
title: Influence of early parental emotional abuse and support on health in middle and late adulthood

description: This dissertation examined whether: 1) parental emotional abuse and support influenced physical and psychological health outcomes later in adulthood; 2) the associations were mediated by self worth, social support, and avoidant coping; 3) parental emotional abuse and support contributed to physical and psychological stress reactivity. Hypotheses were tested by performing structural equation modeling analyses on data from the National Survey of Midlife Development in the United States (MIDUS; 1995-2005); the National Study of Daily Experiences II (NSDE-II; 2004-2009); and the Longitudinal Study of Generations (LSOG; 1971-2005). Higher early paternal emotional support was associated with better self-rated health and more positive affect in adulthood. The association was partially mediated by self worth, social support, and avoidant coping. Maternal emotional abuse was associated with greater daily emotional distress, whereas maternal emotional support attenuated negative emotional reactivity to daily network stress. These findings are discussed in relation to theories of attachment, cumulative advantage and disadvantage, and implications on stress and coping across the lifespan.
DOI: 10.25549/usctheses-c127-623623
title: Tetraspanin18 regulates angiogenesis through VEGFR2 and notch pathways

description: This work is to identify one of Tetraspanin family members, designated Tetraspanin18 (Tspan18), for expression in the developing blood vessels. Tspan18 knock down in zebrafish results in defective spouting, mis-patterning as well as regression of newly formed intersegmental vessels. Investigation of mechanism of action by global and targeted gene expression studies indicates that Tspan18 regulates VEGF/VEGFR2 and Notch/Dll4 pathways. Tspan18 knock down markedly reduced the expression of VEGF/VEGFR2 and downstream targets Notch, and EphrinB2 that are necessary for arterial phenotype and up-regulates EphB4 that defines venous phenotype. Conversely, Tspan18 knock down up-regulates Sema3ab/Nrp-plexinD1 which guide vessel positioning. Tspan18 deficient phenotype can be fully rescued by introduction of VEGFR2 or activated Notch while only partial rescue can be achieved with reduction of Semaphorin or PlexinD1. ❧ In vitro studies confirmed Tspan18 expressed in endothelial cells, and knock down resulted in loss of EC cell migration, invasion and tubular formation. Furthermore, Tspan18 knock down inhibits endothelial VEGFR2 and Notch expression and introduction of VEGFR2 or activated Notch corrected endothelial cell effects. Wound healing studies confirmed up-regulation of Tspan18 expression during remodeling and return to basal level within 7 days. Taken together, our findings reveal that Tspan18, a specific vessel marker, guide arterial development and modulate angiogenesis via VEGFR2 and Notch signaling pathways.