Developmental Education Programs : Students' Perceptions of the Effectiveness at the Community College Level

Mitchell, Thad David Louisiana State University and Agricultural & Mech 2013 해외박사(DDOD)

Developmental education and the surrounding issues of academically underprepared students have been an ongoing source of debate within American higher education. While secondary education systems are frequently blamed for failing to adequately prepare students, community colleges, state colleges, and universities offer developmental programs to aid students in need of remediation in the form of developmental courses. Reading, Math, and English are subjects that are often taught on a developmental level. These courses are designed to provide students with the basic skills needed to be successful in higher education.This research was designed to examine students’ perception of the effectiveness of developmental education programs in a community college setting in Louisiana. The data was collected through a qualitative study using student surveys and interviews. For this study, effectiveness was defined in two ways: in evaluating students’ perception of whether the developmental courses taken address their deficiencies in each developmental course subject and through comparison of components of developmental programs to established indicators that facilitate developmental program success.Theoretical framework for the study drew on Baxter Magolda’s Epistemological Reflection Model. This study contributes to the discussion of effective developmental education pedagogy and the development of programs that enhance underprepared students’ transitional development into a postsecondary educational setting.

Popular Culture Imaginings of the Mulatta: Constructing Race, Gender, Sexuality, and Nation in the United States and Brazil

Mitchell, Jasmine University of Minnesota 2013 해외박사(DDOD)

Through a hemispheric framework, this dissertation explores how national, transnational, and racial identities have been mobilized through contemporary media representations of the mulatta/mulata (woman of African and European descent) figure in the United States and Brazil. Key to the national imagination, the mulatta figure embodies racialized sexual desires and tensions. Chapters One through Four compare U.S. and Brazilian histories, tropes, star texts, and cultural productions concerning mixed-race women of African descent. Chapter Five uses a transnational approach to consider the mixed-race figure. The dissertation uses both comparative and transnational methodologies to engage with a hemispheric framework. Through a hemispheric approach, this dissertation attempts to elucidate intersections and tensions of national, gender, sexual, class and racial formations and to uncover the very assumptions that construct these formations. As each country's historical and ideological responses towards racial mixing generated different national identities, images of the mulatta reflect these racialized national identities. At this juncture, the paths of Brazil and the United States are intersecting so that understandings of race in the United States and Brazil are becoming more similar. The dissertation shows how mixed-race discourses have upheld as well as resisted dominant racial ideologies. By examining media depictions of mixed-race actresses in both countries, the dissertation also shows how racial self-labeling repudiates national racial topographies. Using case studies from Hollywood films and U.S. and Brazilian television shows and star texts of mixed-race actresses, my dissertation argues that popular culture images of the mulatta demonstrate these shifts and that ideas of utopian mixed-race societies often operate concurrently with desires to manage or contain blackness and nullify racialized differences. The idea of the mixed-race figure of European and African descent then is hemispherically circulated such that similar indicators of sexual availability are signified in both countries. The last chapter explores the transnational dimensions of racial imaginings through an analysis of how Brazil is represented in U.S. cultural productions to mediate contemporary U.S. anxieties and desires around race and national identity. The dissertation ends with the upcoming Rio 2016 Olympic Games to examine how Brazil projects itself to the world. As the idea of race has been produced nationally and transnationally, my research shows that eliminating racism demands understanding race in both national and transnational contexts.

Strategic pricing decisions: Cognitive and organizational influences on competitive interactions

Mitchell, Scott Eugene University of California, Irvine 2015 해외박사(DDOD)

This dissertation encompasses three papers that empirically examine ongoing competitive interactions in retail gas markets. Each paper takes a different empirical approach to examine how organizational and cognitive factors influence pricing decisions in this market. The first essay examines how multi-unit franchisee ownership and corporate ownership influences competitive behavior reflected in pricing. I use a panel dataset of pricing decisions of multi-unit franchisees and company-owned gas stations to compare two competing mechanisms by which ownership form influences pricing, double marginalization and strategic delegation. I find that franchisees charge higher average prices, supporting the greater influence of double marginalization on price. Contrary to agency theoretic predictions, firm size and geographic dispersion have a negative influence on the price of multi-unit franchisee stations. The second essay explains how spatial distance and competitor similarity influence firm identification of a relevant competitors. In contrast to prior studies that have used surveys to identify competitors managers saw as most important, I identify a firm's competitors by examining the competitive actions and responses of units using data that isolates the timing of price changes in the Los Angeles retail gas market. Consistent with predictions, I find that retail gas stations monitor a small number of rival stations. The results demonstrate that distance to a rival and similarity between competitors on price and the number of pumps at a station interact to influence the weights assigned to competitors. The findings suggest that managers categorize competitors based on a smaller number of key dimensions than previously theorized. The third essay takes a behavioral approach to examining competitive market factors that lead to systematic pricing errors using non-experimental data. While management researchers have studied the causes of suboptimal pricing decisions, previous research has emphasized experimental or aggregate corporate data rather than pricing and performance data from actual competitive interactions. I utilize a hand-collected, longitudinal dataset of prices and performance outcomes for 26 retail gas stations to determine a daily, station specific profit-maximizing price. These prices are then compared to the actual prices charged to assess the accuracy of station pricing decisions. I find that the number of competitors in a market have a positive influence on the accuracy of pricing decisions at low numbers of competitors but a negative influence at high numbers of competitors. Stations with a visible competitor that compete head-to-head set more accurate prices than stations without a competitor visible competitor.

Saving the Market From Itself: The Politics of Financial Intervention

Mitchell, Christopher W The George Washington University 2013 해외박사(DDOD)

What accounts for divergent and unexpected patterns of state response to banking crises? Contrary to predictions of convergence, significantly different patterns persist across countries. Moreover, these are contrary to expectations. States with a tradition of "laissez-faire" economic policy, such as the United States and United Kingdom, rely heavily on intensive and punitive state intervention, including compulsory nationalization of banks. Conversely, states such as Germany, with an "organized capitalist" tradition in which the state plays an active role in managing the economy, favor state intervention on much more generous and voluntary terms. Such states also see far more extensive privately-organized and -funded rescues than the laissez-faire states. I draw on the comparative capitalisms and multi-level governance literatures to explain these patterns by examining the organization of the financial system and the presence or absence of private governance networks. Divergence is explained by different conceptions of the self-interest of healthy banks in times of crisis. In organized capitalist states, a focus on interbank cooperation produces private governance networks, and means that healthy banks are invested in the fate of failing banks and willing to take action to support them. The healthy banks and institutions of private governance organize privately-funded rescues and lobby the state for generous terms of public assistance. By contrast, in the Anglo-American states interbank relations are atomized, with little or no private governance. In such an environment, healthy banks are unwilling to take action to support struggling peers. Thus there are few private rescues, but without healthy bank lobbying state policymakers are free to impose more stringent terms on banks receiving state-funded rescues. Research has been carried out in a combination of interview and archive-based case study research of American, British, and German responses to the 2007-2009 crisis and of quantitative analysis of state responses to banking crises in the advanced industrial world from 1974 to present. This research offers a valuable contribution to the comparative capitalisms and governance literatures. It demonstrates how corporatist capitalist systems perpetuate themselves in time of crisis through political influence rather than economic functionalism. It also offers comparative examples of how private governance or its absence can play a crucial role in shaping responses to banking crises. Moreover, it highlights how private governance can be both boon, through increased burden-sharing by healthy private interests, and bane, by compelling the state to offer more generous assistance.

The role of teacher beliefs and decision practices in the equitable access to educational opportunities in mathematics

Mitchell, Derek Spencer University of California, Los Angeles 2001 해외박사(DDOD)

Despite gains in academic achievement and attainment among racial and ethnic groups over the last 40 years, the relative performance of students from differing backgrounds is far from equal. The causes for the achievement gap are as much structural as ideological. The gap is rooted in systems of economic and social privilege that have created belief systems and practices resulting in differential treatment of students. National programs aimed at eliminating academic difference in achievement based upon race and other factors have had only limited success (IASA, 1994). Because academic success has been increasingly gauged by standardized tests and assessments, instruments sensitive to social stratification, such tests may have reinforced beliefs of school personnel; new policies, however, have emphasized the use of different indicators of student performance. The study addressed how these different indicators related to teacher beliefs and decisions. The study, conducted in a web environment, investigated the effects of educator background, causal attributions, and student ethnicity (displayed in photographs) on placement decisions. The order of causal attribution and placement decision was counterbalanced. Teachers and administrators were presented with a diverse set of 32 students' photographs paired randomly with data profiles containing four types of indicators (norm-referenced test scores, performance categories, grade point average and homework completion information). Based on the given information, educators were asked to recommend students for a challenging mathematics course. The study found that attribution patterns were similar across indicators. Surprising, and counter to expectations, educators were found to make comparable and strong Effort causal attributions to success for students in all ethnic groups. Educators' Effort attributions were significantly lower for the norm-referenced test indicator. Accuracy of nominations was affected by the variance in attributions. The findings did not support the differential use of information for students of different backgrounds. The study was limited to high-performing student profiles and should be replicated on a wider range of student achievement. If substantiated by future research, the study may indicate that educators are valuing norm-referenced tests less and see them less subject to improvement by student effort.

Calculation of realistic charged-particle transfer maps

Mitchell, Chad University of Maryland, College Park 2007 해외박사(DDOD)

The study and computation of nonlinear charged-particle transfer maps is fundamental to understanding single-particle beam dynamics in accelerator devices. Transfer maps for individual elements of the beamline can in general depend sensitively on nonlinear fringe-field and high-multipole effects. The inclusion of these effects requires a detailed and realistic model of the interior and fringe magnetic fields, including knowledge of high spatial derivatives. Current methods for computing such maps often rely on idealized models of beamline elements. This Dissertation describes the development and implementation of a collection of techniques for computing realistic (as opposed to idealized) charged-particle transfer maps for general beamline elements, together with corresponding estimates of numerical error. Each of these techniques makes use of 3-dimensional measured or numerical field data on a grid as provided, for example, by various 3-dimensional finite element field codes. The required high derivatives of the corresponding vector potential strong, required to compute transfer maps, cannot be reliably computed directly from this data by numerical differentiation due to numerical noise whose effect becomes progressively worse with the order of derivative desired. The effect of this noise, and its amplification by numerical differentiation, can be overcome by fitting on a bounding surface far from the axis and then interpolating inward using the Maxwell equations. The key ingredients are the use of surface data and the smoothing property of the inverse Laplacian operator. We explore the advantages of map computation using realistic field data on surfaces of various geometry. Maps obtained using these techniques can then be used to compute realistically all derived linear and nonlinear properties of both single pass and circular machines. Although the methods of this Dissertation have been applied primarily to magnetic beamline elements, they can also be applied to electric and radio-frequency beamline elements.

Metabolic Versatility of the Hydrothermal Vent Worm Riftia Pachyptila: Allying Transcriptional and Metabolic Responses to a Dynamic Environment

Mitchell, Jessica Helen Harvard University ProQuest Dissertations & Theses 2021 해외박사(DDOD)

The climate dynamics of Titan

Mitchell, Jonathan L The University of Chicago 2007 해외박사(DDOD)

We study the climate dynamics of Titan by developing a hierarchy of planetary climate models and theories. We begin with a one-dimensional radiative-convective model of Titan's atmosphere including the greenhouse and antigreenhouse effects and a generalized moist convection scheme. Our simulations indicate the thermodynamics of methane evaporation and condensation play fundamental roles in establishing deep, precipitating convection while maintaining surface energy balance with the weak solar forcing at Titan's surface. We then derive an extension to a steady, analytic theory for the large-scale circulation of an atmosphere and apply the theory to Titan. The theory predicts Titan's meridional overturning circulation, or Hadley cell, spans the globe. Titan's Hadley cell tends to eliminate latitudinal temperature gradients, which is consistent with the observed weak equator-to-pole surface temperature gradients. We expect Titan's Hadley cell to globally converge moisture into the large-scale updraft and suppress convection everywhere else; resulting cloud patterns should appear sparse and isolated in latitude. We then study the seasonal cycle in a zonally symmetric general circulation model of Titan's climate with an unlimited surface supply of methane. This model produces condensation consistent with the position and timing of observed clouds, but only with the thermodynamic effect of methane condensation and evaporation included. The large-scale circulation in our simulations latitudinally oscillates with season, which in the annual mean dries the low-latitude surface. However, self-consistent drying of the surface requires an accounting of the methane reservoir. Finally, we present zonally symmetric general circulation model simulations with a soil model for the lower boundary and a finite reservoir of methane. Due to annual-mean moisture divergence of the oscillating large-scale circulation, more than 50 m of liquid methane is removed from the low-latitude surface and deposited at mid and high latitudes. Simulations with total reservoir depths below 50 m completely dry the low latitude surface. All simulations with the soil model produce condensation at positions and times consistent with observed clouds.

Cholera toxin inhibition and EpsF from its secretion system

Mitchell, Daniel David University of Washington 2006 해외박사(DDOD)

Cholera is a severe diarrheal disease that kills several thousand individuals and infants each year. Cholera is currently a disease endemic in many developing countries. The closely related Enterotoxigenic E. coli (ETEC), confers a relatively mild form of diarrhea known as traveler's diarrhea, but is much more widespread than Cholera. ETEC accounts for approximately 200 million diarrhea episodes and approximately 380,000 deaths annually. The causative agents of Cholera and ETEC are the closely related AB5 heterohexameric virulence factors Cholera Toxin and heat-labile enterotoxin, respectively. Both heterohexamers are fully assembled in the bacterial periplasm and secreted by the Type II Secretion System (T2SS) into the extracellular milieu. The T2SS is a large complex of 12-15 proteins that function together to secrete specific proteins such as Cholera Toxin. EpsF is the only multi-pass integral inner membrane protein of the T2SS, and is later examined in depth. Upon secretion, the B subunits of the toxin are responsible for binding to the protruding pentasaccharide of ganglioside GM1, on the surface of host epithelial cells lining the gut. The catalytic A-subunit is carried to the host cells in this manner by the B pentamer, and is eventually brought into the host cell. The catalytic A-subunit ultimately creates an imbalance of ions, which causes an efflux of cellular water to the gut, and produces host dehydration and diarrhea. Various monovalent and bivalent inhibitors of the B-pentamer's GM1 binding pocket are bound to toxin protein, crystallized, and have their structures determined in order to explain binding affinities and improve future inhibitor design.

Service-learning and social justice: Making connections, making commitments

Mitchell, Tania D University of Massachusetts Amherst 2005 해외박사(DDOD)

Much of the service-learning literature in higher education assumes that community service linked to classroom learning is inherently connected to concerns of social justice. While some service-learning practice aims to alleviate oppressive or unfair circumstances and promote "more just relationships," there is little research that examines the effectiveness of service-learning in developing that commitment. The purpose of this qualitative research is to understand how students' experiences in service-learning contribute to their understanding of and commitment to social justice. The program investigated is a four semester critical service-learning experience, named the Citizen Scholars Program, at the University of Massachusetts Amherst. Written assignments and interview transcripts from 11 women who participated in the program comprise the data for this dissertation research. This secondary data set was analyzed using grounded theory methodology to explore connections between students' participation in service-learning and their understandings of and commitments to social justice. The findings from this research suggest that participants in this study did develop more complex conceptions of social justice. Through the critical service-learning experience provided by the Citizen Scholars Program, students report being able to: develop authentic relationships with community members, question the distribution of power in society, and deepen their commitments to social justice. The study identified six properties of social justice sensemaking that appear to influence students' understanding of and commitment to social justice. Reflection on the self and experience, introduction to new information, contradictory experiences, relationships with peers and community members, and the idea of plausibility were all shown to spur students' social justice meaning construction. The findings of this study were used to develop a conceptual framework that charts how the critical service-learning experience of the Citizen Scholars Program facilitates social justice sensemaking. This framework can guide the work of scholars and practitioners who aim or hope to encourage social justice commitments in students. Students left Citizen Scholars with confidence in their views of social justice and a willingness to take action in alignment with those views. This research demonstrates that critical service-learning can foster a greater sense of agency to act in support of social justice.