On the Arithmetic and Geometry of Quaternion Algebras: a spectral correspondence for Maass waveforms
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Let be an indefinite rational division quaternion algebra with discriminant d equal to pq where p and q are primes such that p,q > 2 and let pq be a maximal order in . Further, let pq,p2rq2s,r,s ≥ 1 be an order of index p2rq2s in pq with Eichler invariant equal to negative one at p and at q . Finally, let pq,p2rq2s1 be the cocompact Fuchsian group given as the group of units of norm one in pq,p2rq2s. Using the classical Selberg trace formula, we show that the positive Laplace eigenvalues, including multiplicities, for Maass forms on pq,p2rq2s1 coincide with the Laplace spectrum for Maass newforms defined on the Hecke congruence group Γ0(M) where, M, the level of the congruence group, is equal to p2r+1q2s+1, i.e., the discriminant of pq,p2rq2s.
An Examination of the Goodness of Fit Model: How is the Relationship Between Child Temperament and Behavior Expressed in Different Types of Classroom Environments?
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The present study examined how the relationship between child temperament and behavior is expressed in different types of classroom environments in prekindergarten settings. Other goals of the study were to further operationalize the goodness of fit model in school settings and to evaluate possible interactions of process variables indicative of classroom quality with child temperament to see if these interactions predicted child behavior and social skills. Participants included 130 students and their teachers (N = 11) in three prekindergarten settings. Child temperament was measured using the Total Temperament score from the Teacher and Caregiver Temperament Inventory for Children (TACTIC; Billman & McDevitt, 1998). Classroom quality and environment characteristics were measured using the Program Structure scale of the Early Childhood Environment Rating Scales-Revised (ECERS-R; Harms et al., 2005) and the Sensitivity subscale score from the Caregiver Interaction Scale (CIS; Arnett, 1989). Outcomes in behavioral and social domains were measured using the Externalizing Behavior Problems and Social Skills subscales on the Preschool and Kindergarten Behavior Scales- Second Edition (PKBS-2; Merrell, 2002). Hierarchical linear modeling indicated that child temperament alone was the sole predictor of child externalizing behavior, while child temperament, disability status, and school program structure predicted child social skills. Overall, the study indicated that the goodness of fit model when operationalized in terms of the transactional relationship between temperament and environmental demand factors of characteristics of the classroom setting (as informed by the classroom quality literature) has predictive value and describes child behavioral and social outcomes in prekindergarten settings.
Pilgrimages to the Past: Place, Memory, and Return in Contemporary Life Writing
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Pilgrimages to the Past draws from recent scholarship on autobiography, memory, and trauma, while attending to the historical and ethnic specificities of each text. Extending beyond an inquiry into how autobiographical narratives evoke place and how they present the interplay between location and remembering, my dissertation aims to show that the autobiographical impulse, or the desire to tell one's life story, is intimately bound with specific locations that inspire and facilitate remembering. Return lends the past new urgency and propels its narrative reconstruction. An important concept in this project is the dialogic dimension of the homonym routes/roots, which Susan Stanford Friedman sees as integral to processes of identity formation in an age of increased mobility. This analysis of the recuperative potentialities and reparative limits of return seeks to explore place as identity's foundational and transformational site. Going back affirms the returnees' connection to places from the past; at the same time, return changes how they perceive and inhabit their location in the present. Although returns are retrospectively oriented, they propel a prospective engagement with the past that both acknowledges its relevance and accepts its irretrievability. Insofar as visiting places of ancestral or personal significance ultimately leads to an incorporative separation from the past, Pilgrimages to the Past posits that journeys of return are, in fact, journeys of departure that result in the returnee's turn towards present and future. The diasporic quest for origins organizes Eva Hoffman's After Such Knowledge: Memory, History, and the Legacy of the Holocaust (2004) and Daniel Mendelsohn's The Lost: A Search for Six of Six Million (2006). In Running in the Family (1982) and My Brother (1997), Michael Ondaatje and Jamaica Kincaid, two writers of the postcolonial experience now living in North America, play on "the return of the native" theme as they describe visits to their home islands, Sri Lanka and Antigua, respectively. The predicament of exilic homecoming, in turn, is the key theme in Marjane Satrapi's Persepolis 2: The Story of a Return (2003). Revisits to places of personal significance, rather than to a place of origin, give narrative shape to Susan J. Brison's Aftermath: Violence and the Remaking of a Self (2002), Joan Didion's The Year of Magical Thinking (2005), and Alix Kates Shulman's To Love What Is: A Marriage Transformed (2008).
The influence of hepatocyte growth factor during phagocytosis by retinal pigment epithelium
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Processing of photoreceptor outer segments (OS) by the RPE is critical for maintaining the health of the neural retina. If any portion of OS processing is disrupted, or if the RPE suffer injury, subsequent inhibition of OS processing has deleterious effects. Therefore, it is crucial to understand OS processing in order to maintain visual health.1 Sub-retinal clearance of OS by RPE is facilitated by phagocytosis featuring both RPE-specific and Fc gamma receptor associated signaling cascades.2 Integration of these two pathways renders RPE capable of internalizing both specific and non-specific targets. To accomplish these tasks, there must be specific pathways available to present the cell with the protein machinery necessary for binding, internalizing and processing OS. The discovery that lack of c-Met signaling results in impaired phagocytosis in alveolar and hepatocyte macrophages suggests c-Met's role as modulator of phagocytosis.3 These data also suggest a role for hepatocyte growth factor (HGF), the natural ligand for c-Met activation, in preparing phagocytes for clearance of cellular debris. We propose that HGF activation of c-Met in RPE prepares these cells for phagocytosis by initiating a signaling cascade that includes activation of phosphatidylinositol-3 kinase (PI3K). Subsequent activation of Rac1 by PI3K may regulate phagosome formation.4,5
Performed Identities: Theorizing in New York's Improvised Music Scene
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This research looks at the diverse approaches to musical practice in New York City's improvised music scene. Using the ideas of improvisers living and working in New York, a central aim of this study is to explore the development of a musician's music theory as personal and implicit. Theory is defined here as a subjective and internalized body of knowledge informing the particular choices an individual improviser makes in real time, given an aesthetic landscape consisting of many other theories. The eighteen interviewees were each asked a series of questions pertaining to their experience as contemporary improvisers. From analysis of these interviews, three central topics emerged, which form the basis for the chapters of the dissertation. First, theory is an expression of an individual's identity, and that identity is performed in the act of improvisation. Second, there is a causal link between one's theory and one's musical practice, and this link is often expressed through "extra-musical" metaphors pertaining to the body. Third, the project holds that improvisation is an ethical act, the working out of musical and structural processes in real time, requiring a negotiation between the implicit theories of individual players whose aesthetic beliefs may be quite different from one another.
AN ITEM STIMULUS APPROACH TO UNDERSTANDING TEST ITEM DIFFICULTY
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Understanding what makes test items difficult is an important step in understanding how individuals solve items on a test and in mapping the cognitive processes that are involved. However, there remains a gap in understanding how general stimulus features of items (e.g., length of a test item) impact the difficulty of items for a range of item types. In an effort to reduce this gap, the current study tested the impact of item stimulus features on item difficulty. The proposed difficulty framework utilized the radical and incidental approach of item generation theory (e.g., Irvine, Dann, & Anderson, 1990), which allows items to be decomposed into the factors that are hypothesized to impact difficulty as well as examine the impact of different item stimulus features on difficulty. To test the proposed framework, the current paper incorporated linear latent trait modeling (Fischer, 1973), an IRT-based analytical approach that expresses item difficulty in terms of underlying factors of stimulus complexity rather than individual parameters. Results indicate that certain item stimulus features, including language ambiguity, negative wording, constructed-response items, and colloquial knowledge impact item difficulty. Implications for test development are discussed.
THE TRANSFORMATION OF NARRATIVE: AN EXPLORATION OF ALLITERATION'S FUNCTION IN VLADIMIR NABOKOV'S AUTOBIOGRAPHY
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The following is a psychoanalytic inquiry that uses the successive publishings of Vladimir Nabokov's autobiography to explore the functions that various versions of repetition play in transforming traumatic or conflicted memories into narratives that represent more symbolized and coherent accounts of the self. The data set consists of the three, successive, published, English language versions of Nabokov's memoirs. These successive versions are useful in that they represent Nabokov's repeated return to the significant memories and material that compose his autobiographical narrative. With each returns, Nabokov made meaningful revisions to his narrative. Consequently, his transformations are tracked over the course of the successive, drafted versions. Specifically, this project focuses on one chapter of Nabokov's autobiography--"Mademoiselle O"--she being a figure who loomed large in the early part of Nabokov's life. This project proposes that repetition manifests in any one of three main forms: as static repetition, as means for transformation, or as a means of creative play. In addition it proposes that these forms of repetition correspond to a continuum of symbolization, with desymbolized stasis on one end and symbolized play on the other. Here, alliteration was identified as a signifier for these varied forms of repetition. Two main hypotheses are proposed. The first states that if alliterative repetition marks emotionally salient material, then the concentration of alliteration in Nabokov's autobiographical narrative would be greater in areas that contain his most conflicted themes--loss and exile. Indeed results reveal significance. The second hypothesis proposes that if alliterative repetition serves a transformative function, then the concentration of alliteration would decline over the course of Nabokov's progressive drafts. Results are not significant but do reveal a trend toward increase in the final draft. The discussion explores various possibilities as to the given results. It is suggested that Nabokov may have increased his use of alliterative repetition because of the pleasure derived out of mastery and play. Alternatively, it is suggested that alliteration might facilitate internalization, in this case where reader internalizes author and work, thus resulting in Nabokov being better remembered by his readers, an elegant solution to his concerns around loss and being lost.
Respecting Hair: The Culture and Representation of American Women's Hairstyles, 1865-90
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Respecting Hair: The Culture and Representation of American Women's Hairstyles, 1865-90 by Elizabeth L. Block Adviser: Professor Kevin D. Murphy Using a hybrid approach that merges art historical and material culture inquiry, this dissertation recognizes the centrality of hairstyles in figure painting, both portraiture and genre, and photography of the mid- to late nineteenth century in the United States. After establishing the pervasive reach of hair's culture and industry (Chapter One), it argues that artists exploited women's hairstyles as a way to convey commentaries on such topics as conspicuous consumption and monetary wealth (Chapter Two), social class and the development of the modern woman (Chapter Three), the New Woman (Chapter Four), publicly exposed women "à la toilette" and "en déshabillé" (Chapter Five), and overt sexuality (Chapter Six). It considers the specific ways in which artists depicted hair and how that treatment helped achieve their goals. It affirms that hair deserves serious attention with regard to its cultural significance, specifically within the American art historical context of the nineteenth century, which has not been addressed in any publication to date. The study begins in the mid- to late 1860s with the considerable rise in new advertising, products, and services related to hair after the Civil War and how these phenomena were treated by artists. It proceeds to discuss the entrenchment of the Cult of True Womanhood of the 1860s and 1870s, which had a patriarchal and conservative effect on hairstyles and their depiction in art. The emergence of the New Woman, which brought about a radical consideration of hairstyles about 1890, provides an end point. By tracing the development of women's hairstyles, this dissertation contends that the study of hair should take its place with readings of other visual culture in paintings, such as clothing, furniture, and interior decoration that broaden our view into the motivations behind cultural changes. The study highlights the following artists: Aaron Draper Shattuck (1832-1928); Thomas Pritchard Rossiter (1818-1871); Eastman Johnson (1824-1906); Winslow Homer (1836-1910); Alice Austen (1866-1952); Mary Cassatt (1844-1926); and John Singer Sargent (1856-1925).
Unemployed and Poor in New York: The Impact of Object Relations, Mentalization and Psychopathology on Job Outcome
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This study examined the relationships between the quality of internal object representations of self and other (OR), the capacity for reflective functioning (RF) and the presence of Axis II psychopathology and their respective and combined impact on the ability of unemployed, low-income individuals to complete job readiness training, and to obtain and retain employment. Given the intertwining nature of these constructs, it was expected that correlations would exist between OR, RF and Axis II psychopathology and that these constructs would also be related to job outcome, such that those with low OR and RF or those with Axis II psychopathology would experience greater difficulty in completing job training, let alone obtaining and maintaining employment. This research study posed additional research questions to examine the extent to which each of these variables would account for the variance in job outcome. It also sought to investigate the extent to which the predicted relationship between OR and job outcome would be moderated or mediated by Axis II pathology or the degree of RF present, such that an individual with significant psychopathology or low RF capacity would be expected to have poor job outcome regardless of OR scores. Similarly, it examined the question of whether the proposed relationship between Axis II pathology and job outcome would be moderated or mediated by the degree of RF present, such that those with a more developed capacity for RF would have better job outcome despite the presence of Axis II pathology. Results partially supported the study's main hypotheses in that RF and Axis II pathology were not only found to be related, but also to significantly predict job outcome. Moreover, it was determined that in those cases where participants with Axis II diagnoses were able to obtain jobs, their ability to obtain the job was entirely attributable to the presence of relatively higher levels of RF. This finding suggests that the presence of even a moderate capacity to consider and to reflect upon the mental states of self and other confers an advantage on those with Axis II diagnoses in the pursuit of gaining employment. OR findings were less robust although one of the subscales of OR, Complexity of Representations, was found to be significantly associated with RF in the predicted direction. These results are discussed in relation to implications for the design of programs and interventions to assist unemployed and underserved populations.
MESSAGE PASSING TECHNIQUES FOR STATISTICAL PHYSICS AND OPTIMIZATION IN COMPLEX SYSTEMS
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Optimization problem has always been considered as a central topic in various areas of science and engineering. It aims at finding the configuration of a large number of variables with which the objective function is optimal. The close relation between optimization problems and statistical physics through the probability measure of the Boltzmann type has brought new theoretical tools from statistical physics of disordered systems to optimization problems. In this thesis, we use message passing techniques, in particular cavity method, developed in the last decades within spin glass theory to study optimization problems in complex systems. In the study of force transmission in jammed disordered systems, we develop a mean-field theory based on the consideration of the contact network as a random graph where the force transmission becomes a constraint satisfaction problem, with which the constraints enforce force and torque balances on each particle. We thus use cavity method to compute the force distribution for random packings of hard particles of any shape, with or without friction and find a new signature of jamming in the small force behavior whose exponent has attracted recent active interest. Furthermore, we relate the force distribution to a lower bound of the average coordination number of jammed packings of frictional spheres. The theoretical framework describes different types of systems, such as non-spherical objects in arbitrary dimensions, providing a common mean-field scenario to investigate force transmission, contact networks and coordination numbers of jammed disordered packings. Another application of the cavity method is immunization strategies. We study the problem of finding the most influential set of nodes in interaction networks to immunize against epidemics. By means of cavity method approach, we propose a new immunization strategy to identify immunization targets efficiently with respect to the susceptable-infected-recovered epidemic model. We implement our method on computer-generated random graphs and real networks and find that our new immunization strategy can significantly reduce the size of epidemic.