The developmental trajectory of contour integration in autism spectrum disorders
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Sensory input is inherently ambiguous and complex, so perception is believed to be achieved by combining incoming sensory information with prior knowledge. One model envisions the grouping of sensory features (the local dimensions of stimuli) to be the outcome of a predictive process relying on prior experience (the global dimension of stimuli) to disambiguate possible configurations those elements could take. Contour integration, the linking of aligned but separate visual elements, is one example of perceptual grouping. Kanizsa-type illusory contour (IC) stimuli have been widely used to explore contour integration processing. Consisting of two conditions which differ only in the alignment of their inducing elements, one induces the experience of a shape apparently defined by a contour and the second does not. This contour has no counterpart in actual visual space - it is the visual system that fills-in the gap between inducing elements. A well-tested electrophysiological index associated with this process (the IC-effect) provided us with a metric of the visual system's contribution to contour integration. Using visually evoked potentials (VEP), we began by probing the limits of this metric to three manipulations of contour parameters previously shown to impact subjective experience of illusion strength. Next we detailed the developmental trajectory of contour integration processes over childhood and adolescence. Finally, because persons with autism spectrum disorders (ASDs) have demonstrated an altered balance of global and local processing, we hypothesized that contour integration may be atypical. We compared typical development to development in persons with ASDs to reveal possible mechanisms underlying this processing difference. Our manipulations resulted in no differences in the strength of the IC-effect in adults or children in either group. However, timing of the IC-effect was delayed in two instances: 1) peak latency was delayed by increasing the extent of contour to be filled-in relative to overall IC size and 2) onset latency was delayed in participants with ASDs relative to their neurotypical counterparts.
The Ecology of the Woodlands of Central Park, New York City
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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. As a fully human-made park under continual management, these woodlands contain a high percentage of non-native and horticultural species. A survey of the biodiversity of the park, however, shows the significant role even a highly managed park can play in wildlife habitat. Invasive plants are a serious threat to native plants and wildlife habitat everywhere. Numerous invasive species are present in Central Park. This study evaluates management practices to control these species and makes further recommendations. It analyzes the potential of other non-native species, as well as native species, to become invasive. This study can help park managers decide which plants to highlight and preserve and which to manage and control.
Brokering Literacies: An Ethnographic Study of Languages and Literacies in Mexican Immigrant Families
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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. Through ethnographic observation and analysis of oral and written language at the program's center, the study examines the rhetoric of "brokered" social relations in the bilingual exchanges among the organization's volunteer staff of college and high school student mentors and its numerous youth and adult members, paying particular attention to documenting the various linguistic skills developed by bilingual youth, mentors, and parents. I argue that the notions of culturally valuable literacy skills of translation and language brokering, undervalued and existing outside the dominant models of school culture and literacy practices, were actively utilized at the center. Day-to-day translations between languages for the children participants at this mentoring program meant involving and engaging monolingual family members in their schooling lives, which were largely conducted in a second language. This collaboration in immigrant families, though, produced conflicts from linguistic inequalities which re-distributed authority in family linguistic exchanges. The program's mentors mediated such shared power contexts, allowing language minority parents access to collaboration in their children's educations in English, while also encouraging language brokering skills among young bilinguals.
'The Duty of Woman by Woman': Exploring Female Friendships in Jane Austen's Novels
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Though men populate the pages of Jane Austen's novels, her interest is not in a male world. This dissertation argues that the central theme of Austen's oeuvre is not marriage, but the bonds forged within female same-sex networks: the three kinds of friendships in which Austen's heroines engage--defined by ties of blood, surrogate kinship, or circumstance--ease them into heterosexual society while allowing them to challenge some of the institutions and conventions that define them as nonentities. Ranging from devotion to manipulation, the three types of friendship present in Austen's six published novels allow the heroines to experience both supportive understanding and competititive hostility in a safe environment. This work argues that the attachment between each protagonist and another woman promotes a strong sense of identity that allows her to enter into the larger society surrounding her female world from a position of strength through marriage--the heroine's only venue of social recognition, visibility, and success. Here, I contend that Jane Austen's novels portray friendships between women as the strongest source of female identity because the self-awareness they advance allows the heroine to resist her culture's unwillingness to acknowledge her as an intellectual and moral agent.
Influences of the Female Reproductive Cycle on Inflammatory Induced Pain Resonses
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Abstract Influences of the Female Reproductive Cycle on Inflammatory Induced Pain Responses by Nicole J. Amador Advisor: Professor Vanya Quiñones-Jenab Clinical and preclinical studies have demonstrated significant sex differences in the perception of inflammatory pain; females display higher nociceptive responses to inflammatory stimuli than male rats. Additionally, the complex endocrinological profile of females has been shown to impact their nociceptive responses. For example, estradiol reduces Phase II behavioral-nociceptive responses after formalin administration. However, little is known about the specific biological pathway(s) and/or mechanisms in which cycling endogenous female sex hormones affect inflammatory pain responses. Current literature has established that cyclooxygenases and prostanoids are major pro-inflammatory mediators directly linked to inflammatory responses. Additionally, glucocorticoids, (i.e. corticosterone) negatively regulate inflammatory induced COX-2, resulting in attenuation of inflammatory responses. The objective of this study was to further understand how fluctuations of endogenous female sex hormones alter inflammatory-induced responses by examining two physiological pathways (i.e. NO/COX-2 regulation of the prostanoid biosynthetic pathway and corticosterone regulation of the NO/COX pathway) which may in part be responsible for these effects. Endogenous peaks of estrogen and progesterone during proestrus, were shown to significantly attenuate behavioral responses after formalin administration. This attenuation of behavioral responding was accompanied by a significant increase in PGD2 serum levels. Cortiscosterone serum levels were unaffected after formalin administration suggesting that regulation of behavioral responses by endogenous hormones may be occurring through a pathway independent of the corticosterone biosynthetic pathway. COX-2 and nNOS levels in the spinal cord were not significantly affected by the estrous cycle, suggesting that regulation of behavioral responses by endogenous hormonal fluctuations may be occurring through a pathway independent of the NO/COX biosynthetic pathway. Furthermore, although no estrous cycle effects were seen in paw withdrawal latency after carrageenan administration, we observed estrous cycle effects in the contralateral paw at baseline and one hour post-injection. Rats in proestrus showed a significant reduction in thermal- induced hyperalgesia as measured by increased paw withdrawal latency. Although no significant differences were seen in PGD2 serum levels, rats in estrus had significantly higher PGE2 serum levels after carrageenan administration. A significant decrease in PWL was observed in rats during estrus, a time of the lowest levels of fluctuating hormones. These results suggest that hormonal troughs during the cycle may affect inflammation through the PG biosynthetic pathway. Finally, during ages when animals are considered "middle aged" attenuation in inflammatory induced behavior was observed. This finding was accompanied by significant decreases in PGE2 and PGD2 levels and a significant increase in corticosterone serum levels. Taken together these results suggest a relationship between endogenous hormonal fluctuations, corticosterone release and PG activity. In summary, our results suggest that endogenous hormonal peaks and troughs effects on inflammation may be mediated through the regulation of the NO/COX-2/prostanoid biosynthetic pathway.
Race and Realism in Edward Harrigan's Mulligan Guards Series
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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. The two key terms to my study are "race" and "realism." Rather than imposing contemporary definitions onto these concepts, I examine the terms in their contemporaneous usages. I show how Edward Harrigan's work embodies the meeting point of Realism and the entertainments which held sway in America prior to the arrival of Realism. Harrigan, along with more "serious" dramatists, instilled an expectation for Realism on the stage, the ramifications of which are still felt in American theatre. Harrigan's works enacted particular cross sections of New York life in very specific neighborhoods - replete with the various denizens of these neighborhoods. Harrigan's Americans inhabit the poorer areas of working class New York and his portraits of these characters are extremely detailed in their wants, pursuits, peeves and drives. At the core of the Mulligan Guard series, and indeed most of Edward Harrigan's plays lies the depiction of the New York Irish community and, to a slightly lesser extent, the African American community. Surrounding these core groups stand a variety of ethnicities: German, Chinese, and Eastern European Jews. Harrigan's approach to Realism is explored thoroughly through reportage of his productions, specifically that of the Mulligan Guard series, in light of Harrigan's own assertions as to his approach to his craft. I examine the use of Realism in regard to the depiction of race. When considering the depiction of race, Harrigan's characters cannot literally be accepted as authentic because of the actors in the roles (White actors performing Black), but my study shows how authenticity of racial depiction was regarded in its own age. Methodology Because of the nature of this study, I combine research methods from a variety of scholars. I reconstruct the period in order to approach Harrigan's work historiographically. I examine not only the written text but the audience, demographics of New York City, other forms of entertainments at the time, critical writing, and illustrations. Of chief importance to this study are the various collections and scrapbooks of Harrigan's work. The Billy Rose Theatre Collection at the New York Public Library has a vast collection of Harrigan's work, clippings, scripts, songs, and the like. Alicia Kae Koger's two-part exhaustive bibliography on Edward Harrigan is invaluable to this study. In addition to the collection in New York, Harrigan materials exist at various public and private libraries, particularly the Library of Congress.
Referring and Describing: Three Essays on the Meaning and Use of Definite Descriptions and Complex Demonstratives
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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
Don Anton Amarasinghe
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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. Results show that the maximum effective lateral diffusion length of iron in PVG is <10 μm at 650C. We conclude that the particle growth which occurs at 650C is due to a less than 10 μm diffusion length within the matrix. XANES results show that elemental iron found in the PVG immediately after photolysis is concentrated in the interior of the glass. Although some elemental iron is found on the surface of the glass they are covered with a protective layer of Fe(III) oxides. This protective layer seems to be robust enough to prevent further oxidation of elemental iron particles during the annealing process at 6500C but the elemental iron found in the interior of the glass did oxidize during the annealing process until the protective layer of Fe(III) oxide is formed. The results suggest that once the Fe(III) / Fe(0) ratio reach a critical value further oxidation is prevented. EXAFS data analysis along with EPR confirmed that the chemical nature of iron oxides formed on the surface and the interior of the PVG are identical and Fe(III) is in an octahedral environment. The Mössbauer data suggest that the Fe(0) particles in the PVG substrate are randomly oriented whereas Fe(III) has some orientation suggesting that particles are attached to the silica substrate through the oxide envelope. Unlike Fe(CO)5 doped PVG, when Fe(CO)5 doped MCM-41 is photolyzed, it leads to formation of octahedrally and tetrahedrally coordinated iron sites within the silica matrix. Mossbauer study shows that with the increasing temperature, iron migrates from octahedral sites to tetrahedral sites. Iron in xerogel behaves differently than iron in PVG or MCM-41. Iron migration into tetrahedral sites initiates at 650C and the number of tetrahedral sites increase with temperature. Neither xerogel nor MCM-41 shows any evidence of elemental iron before or after heat treatments. The Fe(0) formation in PVG seems to be a unique phenomenon.
Alien Spaces: Planning, Reform, and Preservation on the Lower East Side, 1880-2002
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In this project, I trace the ways in which reform and urban planning discourses, shored up by a desire for ethnic and racial regulation, defined the Lower East Side as an "alien space," both removed from and problematic for the rest of New York City over the long twentieth century. I argue that this sustained discourse of "alienness" in the service of regulation - varying from Progressive reform efforts at the turn of the twentieth century to the racially-charged citizen participation efforts of the mid-twentieth century urban renewal era to the battle for community preservation in the face of increasing gentrification at the turn of the twenty-first century - had a direct impact on the built environment of the Lower East Side. This approach to the neighborhood's formation and development not only links language (the discursive production of the area) with action (its demolition, construction, reconstruction, and preservation), it also highlights the profound fissures that existed in liberal reform, particularly with regard to race and ethnicity. Even when ambivalence toward the Lower East Side's ethnic population was not readily apparent, as in the language of social science and the maps of urban planning, it was implied by ongoing questions about the fitness of Lower East Siders to determine the fate of their own neighborhood.
The Politics of Laughter in Ariosto's "Orlando Furioso" and Cervantes' "Don Quixote"
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Abstract The Politics of Laughter in Ariosto's Orlando Furioso and Cervantes' Don Quixote By Rosa Amatulli Adviser: Professor Clare Carroll This dissertation explores the function of laughter in the Orlando Furioso and Don Quixote. Contrary to those who consider laughter an emotional release devoid of social and political importance, this study will show that laughter is a very powerful social and political world view. For Ariosto and Cervantes laughter was a most appropriate literary vehicle with which to respond to the great social and political changes of their time. Embodying the political climate of their milieu, their characters are ridiculous because they fail to be political in the Platonic-Aristotelian sense of the word politiké and because they fail to engage with the political life of their communities. These characters are idions, that is to say, they are ridiculously unethical: they are irresponsible and apolitical, and as such they are ridiculed. In order to understand the social-political aspects of laughter, we will first have to answer the question, what is a system of ethics. A system of ethics aims to prescribe the right kind of social action according to different situations: political, military, economic, etc. Plato's and Aristotle's philosophies, and Pico della Mirandola's and Leonardo Bruni's theories, will demonstrate that systems of ethics are not transcendental but answer to different situations, and that an ethics is the prescription for social behavior and not merely individual behavior. For example, the knights in the Orlando Furioso are ridiculous for two main reasons: one, because they are swayed by their appetites and two, because they are not loyal to the principles of knighthood, and specifically to their political, ethical and moral duties. Don Quixote, on the other hand, is ridiculous for opposite reasons. Forgetful or, neglectful of the contemporary social and economic life-world around him, Don Quixote is obsessively loyal to a set of ethics relevant only to chivalry, and not to his contemporary society. Thus, while the knights in the Orlando Furioso are derided for being individualistic and devoid of any high ideals, for failing to behave in ways conducive to the common good, Don Quixote suffers ridicule for being too idealistic and for attempting to enforce certain ideals that have no relevance given the contemporary state of affairs--illustrative of the fact that moral values and ideology are historically bound. Four chapters constitute the main body of this dissertation: Chapter I is devoted to Plato and Aristotle's conceptualization of ethics and laughter and, Chapter II is dedicated to the Renaissance understanding of political and ethical agency in the philosophies of Leonardo Bruni and Pico della Mirandola. After proposing the relationship between politics and ethics in the first two chapters, Chapter III analyzes the ridiculous behavior of the idions in Ariosto's Orlando Furioso and Chapter IV analyzes the honorable--yet foolish conduct of the knight in Cervantes' Don Quixote.