Molecular Dynamics of Shock Wave Interaction with Nanoscale Structured Materials
Year of Dissertation:
2012
Advisor:
Yiannis Andreopoulos
Typical theoretical treatments of shock wave interactions are based on a continuum approach, which cannot resolve the spatial variations in solids with nano-scale porous structure. Nano-structured materials have the potential to attenuate the strength of traveling shock waves because of their high surface-to-volume ratio. To investigate such interactions we have developed a molecular dynamics simulation model, based on Short Range Attractive interactions. A piston, modeled as a uni-directional repulsive force field translating at a prescribed velocity, impinges on a region of gas which is compressed to form a shock, which in turn is driven against an atomistic solid wall. Periodic boundary conditions are used in the directions orthogonal to the piston motion, and we have considered solids based on either embedded atom potentials (target structure) or tethered potential (rigid piston, holding wall). Velocity, temperature and stress fields are computed locally in both gas and solid regions, and displacements within the solid are interpreted in terms of its elastic constants. In this work we present results of the elastic behavior of solid structures subjected to shock wave impact and analysis of energy transport and absorption in porous materials. The results indicated that the presence of nano-porous material layers in front of a target wall reduced the stress magnitude detected inside and the energy deposited there by about 30 percent while, at the same time, its loading rate was decreased substantially
Making Conversation: The Poetics of Voice in Modernist Fiction
Year of Dissertation:
2012
Program:
Comparative Literature
This dissertation examines the function of dialogue within modernist fiction, and argues that it can be seen to assume a substantially expanded and diversified role in early twentieth-century narrative texts. While existing accounts of fictional speech stress its capacity to develop character or advance plot, I contend that modernist authors began using speech differently than it had historically been used in the novel: less for characterizing and plot-advancing purposes, than for rhetorical and poetic ones. My primary case studies include a cross-section of British and American modernist texts - including Henry James's The Ambassadors, Ernest Hemingway's The Sun Also Rises, James Joyce's "The Dead," Virginia Woolf's The Waves, and William Faulkner's The Sound and the Fury and Absalom, Absalom! - as well as examples from post-War Italian narrative, which reflect the influence of Anglophone modernism. Through close, comparative analyses of how fictional voice is deployed in these texts, and by drawing on a range of literary and narrative theory (by Mikhail Bakhtin, Franco Moretti, and Sharon Cameron among others) I demonstrate that these writers frequently "make" conversation less to express character, than to communicate ideas or affects that exceed character. In particular, I disclose the tendency for discourse within these fictional environments to belong to more than one speaker - or conversely, to none. By challenging the attributive logic used to make sense of represented speech, these texts encourage us to refocus our critical attention away from discrete utterances, and toward the larger system of utterances that emerges in a given work. In this way, I argue, modernist fiction seems to demand (and reward) a new mode of reading and interpreting fictional dialogue: one which takes into account how characters say, as well as what they say, and which treats dialogue's form as at least as rich a source of meaning as its content.
FACIAL EMOTIONAL EXPRESSION FOLLOWING VOICE TREATMENTS IN INDIVIDUALS WITH PARKINSON'S DISEASE
Year of Dissertation:
2012
A growing body of work has documented impairments in emotional facial expression (i.e., masked facies) in individuals with Parkinson's disease (PD). These impairments negatively impact patients' social interactions and functioning in daily life. However, little attention has been given to remediating facial emotional expression deficits in PD. Preliminary research has demonstrated that the treatment of voice using the Lee Silverman Voice Treatment (LSVT®; Ramig et al., 1995) has beneficial effects on limited aspects of facial expression in PD (Spielman et al., 2003). The present study extends the literature by examining the effects of two voice treatments on facial expression in PD in a comprehensive way, including facial mobility (FM) and three aspects of facial emotional expressivity (i.e., frequency [EF], variability [EV] and intensity [EI]). Participants included 56 posers, individuals who produced emotional and non-emotional monologues, and 18 raters, individuals who rated posers' facial expressions from video-recorded monologues. Ratings were made on a 7-point Likert scale for the four aspects of facial expression. Raters were trained to criterion, and reliability was high for each emotional expression variable (Intraclass Correlation Coefficient range .85 to .90). The study included four poser groups: 3 PD groups whose posers were randomly assigned into an LSVT, Articulation Voice Treatment (ARTIC), or a no treatment control group, and a demographically matched healthy control group (NC). Findings revealed that PD male posers displayed impaired facial expression at baseline compared to NCs on all variables examined, although PD women did not differ from NCs for any aspect of facial expression. Treatment findings showed that patients who received LSVT were rated as having higher FM, EF, EV, and EI after treatment, four weeks later, than at baseline. This increase was not observed for the 3 other poser groups. It is speculated that LSVT improves facial expression because facial and vocal expression are emotional communication channels that exist within a larger network of emotional processing. Facial and vocal emotional expression are linked at several levels of neural organization: cortical, subcortical, and cranial nerve. The broader clinical implications of our findings are that masked facies can be remediated using LSVT.
National Physiology: Literature, Medicine, and the Invention of the American Body, 1789-1860
Year of Dissertation:
2012
"National Physiology" investigates the intertwined discourses of literature and medicine in the proto-disciplinary early American world. It makes three interventions. First, in contrast to existing scholarship that has actively neglected it, I bring to light an important history of early American medicine. Second, I show how American writers produced medical models of their own. Literary figures did not simply reflect medicine in their texts, but used fiction to craft medical philosophies, which they believed directly promoted the health of the nation. Finally, I argue these histories were not separate, but intimately connected: doctors and writers worked together to craft an American body that was metonymically linked to the healthy nation. In mining the relationship between medicine and literature in the early republic, my project is the first to offer a genealogy of the Medical Humanities in America; it also suggests that by looking at this history, we will find promising new models for interdisciplinary scholarship.
The Ecology of the Woodlands of Central Park, New York City
Year of Dissertation:
2012
A quantitative ecological inventory was conducted in the 54.6-hectare (ha) urban woodlands of Central Park, New York City. Fifteen sites were selected and woody stems greater than or equal to one centimeter (cm) diameter were surveyed using the point-centered quarter transect method. Total area surveyed was 1.091 hectares. The survey tallied 1,271 stems from 82 species in 31 families and 50 genera. Stem diameters ranged from 1 cm to 218 cm. In terms of ecological dominance, Prunus serotina Ehrh. was the dominant taxon followed by Quercus rubra L. The largest trees were Quercus rubra, Prunus serotina, Morus alba L., Phellodendron amurense Rupr., Platanus occidentalis L., Liriodendron tulipifera L., Quercus palustris Münchh., Ulmus americana L., and Styphnolobium japonicum (L.) Schott, ranging in diameter from 100 cm to 218 cm. Lower diameter at breast height (DBH) quartile stem sizes were dominated by Acer platanoides L., Prunus serotina, Celtis occidentalis L. and Q. palustris.
Brokering Literacies: An Ethnographic Study of Languages and Literacies in Mexican Immigrant Families
Year of Dissertation:
2012
This dissertation studies how English language acquisition and literacy transformed family relations and structured educational ambitions within a specific Spanish-dominant urban immigrant community. Ten first-generation Mexican-origin immigrant families living in New York City were the focus, all members of a small, under-funded, self-sustained educational mentoring program, whose core of eleven dedicated volunteers were also participants in this qualitative study. The grassroots organization offered free after-school tutoring services while also promoting active family involvement in schooling and positive views toward ethnic and linguistic identities. The organization also helped to mediate and bridge the linguistic miscommunications between schools and language minority parents. In addition, the program cultivated a sense of community and academic participation closely allied to ethnic identity, encouraging a sense of value for bilingualism as a political tool for--and the everyday reality of--immigrant children. Finally, the program also sponsored and reinforced the notion of standard English acquisition as valuable for academic success, while offering a space where standard and nonstandard languages and literacies freely mixed and where bilingual exchanges between individuals openly nurtured, critiqued, and, ultimately, defended the distinctive, monolingual spoken and written standard English language of schooling.
Influences of the Female Reproductive Cycle on Inflammatory Induced Pain Resonses
Year of Dissertation:
2009
Advisor:
Vanya Quinones-Jenab
Abstract
Race and Realism in Edward Harrigan's Mulligan Guards Series
Year of Dissertation:
2009
In this dissertation I examine the written texts and performances of the original productions of Edward Harrigan's Mulligan Guard series as they intersected and embodied the presentation of race and Realism. My study considers the context of the period in which the plays premiered: 1879 - 1884, beginning with the first full-length piece from the series: The Mulligan Guard Ball. Using race performance theory and the theories and history of Realism, I show how Harrigan's work figured prominently at a key point in the history of American theatre, embodying a plethora of contradictions: racism and progressivism; Realism and melodrama.
Referring and Describing: Three Essays on the Meaning and Use of Definite Descriptions and Complex Demonstratives
Year of Dissertation:
2010
This dissertation is composed of three independent essays, and it investigates the meaning and use of definite descriptions and complex demonstratives and the form of complex demonstratives. In the first essay, I tackle the referential-attributive status of definite descriptions. I argue that these expressions are referential-attributive ambiguous in the sense of semantic polysemy - as opposed to homonymy or pragmatic polysemy. In the second essay, I turn to complex demonstratives and argue on methodological grounds that they are non-quantificational terms that refer and describe, descriptive designators I dub them. I also provide arguments against the idea that demonstratives, from a syntactic point of view, are articles in disguise. And in the third essay, I argue against `direct reference' theorists and quantificationalists alike, claiming that complex demonstratives and referential descriptions are descriptive designators. This hypothesis provides the simplest explanation of the full semantic significance of nominals in both expressions.
MICROSTRUCTURAL ENVIRONMENTS AND REDOX STATES OF IRON IN RANDOM AND ORDERED POROUS SILICA MATRICES
Author:
Don Anton Amarasinghe
Year of Dissertation:
2009
In our previous studies we have shown that the refractive index of porous Vycor glass can be changed by doping with iron and at the lower end of the iron loading, the refractive index shows a fairly linear increase with the loading. This allows us to create refractive index patterns in porous Vycor glass. The exact mechanisms regarding image formation in the Vycor glass and the factors that affect the image quality are still being investigated. In this study we analyzed the cross-sectional distribution of iron and the lateral diffusion of iron during the heat treatment in order to understand the contrast variations. The study also focused on microstructural changes of iron particles from the surface to the interior of the porous Vycor glass. The other objective of the study is to understand microstructural variations of iron in regular pore structured materials such as MCM-41 and random pore networks such as xerogel and PVG.