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Referring and Describing: Three Essays on the Meaning and Use of Definite Descriptions and Complex Demonstratives
Year of Dissertation:
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.
NUMERICAL SIMULATION OF MULTIPHASE FLOWS IN MICROCHANNELS USING THE LATTICE BOLTZMANN METHOD
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Dynamics of multiphase systems in micro-fluidic devices is a topic of great interest in many industrial applications such as chemical synthesis, DNA analysis, enhanced micromixing, and power generation. Due to the small transverse dimensions, microchannels provide a great surface to volume ratio, offering an enhanced heat and transfer efficiency. In addition, they provide a great alternative for many chemical reactions by minimizing the amount of reactants needed. Different from large scale channels, bubbles can create significant problems in micro-fluidic devices by altering or blocking the flow. On the other hand, controllable addition of bubbles is desired to improve mixing and heat transfer in microsystems. Therefore it is important to understand clearly the dynamic behavior of multiphase systems, from the point of formation to transport along the microchannel. Bubble formation dynamics is governed by the set-up geometry and ratio between interfacial and viscous forces in the system. Multiphase flow transport along microchannel is determined by wall surface wettability, initial fluid conditions, and velocities. A stable Lattice Boltzmann Method (LBM) based on the Cahn-Hilliard diffuse interface approach is used for the simulation of bubble formation and motion along the microchannel. Initial validation of the model is presented for the dynamics of a single bubble rising in unconfined and confined domains.
Clinical Nurse Faculty and the Lived Experience of Clinical Grading
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Clinical grading is one approach to assure that future nurses have the knowledge and skills to provide safe patient care. The phenomenon being explored for this study was the experience of clinical grading for clinical nurse faculty. Through the use of a qualitative phenomenological method, the lived experience of grading nursing student clinical performance for experienced clinical nurse faculty in pre-licensure programs is described. Eleven full-time nursing faculty were recruited using a purposive technique to obtain a convenience sample. Each participant first underwent an initial in-depth personal interview followed by a brief follow-up interview a few weeks later. The van Manen method of hermeneutic phenomenology was applied to describe and interpret the data while developing an understanding of the experience for the participants. Findings from this study revealed five essential themes. These essential themes were collated to form a textual interpretive statement which illuminated the meaning of the experience of clinical grading for the participants. Barrett's theory of Power as Knowing Participation in Change emerged as one way to reflect on the findings in a way that was meaningful to nursing. Recommendations for future research and implications for nursing are identified.
OPTICAL ALGORITHMS FOR ASSESSMENT OF FLUORESCENCE SOURCES IN SEA WATERS
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An optical algorithm, hereinafter called the Red Band Difference (RBD), is proposed and tested using sun induced chlorophyll fluorescence as the primary tool for the detection of relatively low backscattering phytoplankton blooms from space. The RBD technique is found to have potential for improving identification of blooms and their location compared to other algorithms. Since Karenia brevis (K. brevis) blooms are of great interest and have been commonly reported throughout the Gulf of Mexico, I also propose a K. brevis bloom classification algorithm, hereinafter called the K. brevis Bloom Index (KBBI). The KBBI technique is primarily based on the fact that total particulate backscattering associated with K. brevis bloom is different and much lower than that for non-K. brevis blooms. Since K. brevis bloomed water is known to have lower particulate backscattering than the non-K. brevis bloomed waters, the water-leaving radiance signal is much weaker for K. brevis blooms. As a consequence, the KBBI index becomes much larger for K. brevis blooms than for non-K. brevis blooms, thus permitting their distinction. The RBD and KBBI algorithms are capable of detecting relatively low backscattering blooms and classifying K. brevis blooms respectively from Moderate Resolution Imaging Spectroradiometer (MODIS) and Medium Resolution Imaging Spectrometer (MERIS) ocean color measurements. To assess the efficacy of the detection and classification algorithms, simulations, including chlorophyll fluorescence (assuming 0.75% quantum yield) based on the K. brevis and non-K. brevis blooms conditions were performed and thresholds were determined. The approaches were applied to well documented blooms of K. brevis in the Gulf of Mexico and results were compared to other detection techniques such as Fluorescence Line Height (FLH). The application of the RBD was extended to test capabilities for detecting various toxic dinoflagellates blooms around the world. An analysis of impacts of the atmospheric corrections was performed on both of the algorithms.
COMPUTATIONAL INSIGHTS INTO THE OXYGEN EVOLVING COMPLEX OF PHOTOSYSTEM ΙΙ
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The Oxygen Evolving Complex (OEC) of Photosystem II (PSII) is a unique Mn4O5Ca2+ cluster that catalyzes the photoactivated water splitting reaction. The OEC is a model system for bio-inspired artificial systems to use solar energy to pull electrons from water to produce fuel. The OEC goes through a cycle of 5 S states storing 4 holes, via electron transfer to P680+, the primary electron donor in PSII to generate a high valence S4 state that oxidizes water. The key questions are what controls the order of oxidation and deprotonation of the OEC complex and how does the PSII protein modulate the cluster behavior. Here, we present a classical electrostatics Monte Carlo (MC) technique, with input from density functional theory (DFT) and molecular dynamics (MD) to study the thermodynamics of the S0 to S3 states in a cluster embedded in the whole PSII. The model is tested against model complexes and yields a very good agreement with the experiment. In the simulation, the electrochemical potential (Eh) is varied to oxidize the OEC. The MC sampling allows the Âµ-oxo-bridges, terminal waters and amino acid residues to change their protonation states and/or their rotamer position to respond to the Mn oxidation. In addition, chloride is allowed to move during the cycle. The order of Mn oxidation found here is Mn2, Mn3, Mn4 and finally Mn1 as the system goes from the S0 to S3 states. In the S-1 state O1 and O4 are protonated as are the terminal waters on Mn4 and the Ca2+. O4 and O1 are deprotonated when S0 and S1 are formed respectively. The formation of S2 includes proton transfer from W2 to the nearby D61, reducing the release of protons to the media, consistent with experimental measurements. Protons are also lost from H337 and E329. The proton-release pattern is compared fixing the protonation states for H337, D61, terminal waters and with chloride-depleted PSII. The calculated midpoint potential of each Mn and their dependence on pH is discussed.
The diet and foraging ecology of gray seals, Halichoerus grypus, in United States waters
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Once extinct in U.S. waters, there are now more than 7,000 gray seals (Halichoerus grypus) that breed and forage in the waters of Maine and Massachusetts. This is the first long-term study of the diet and foraging behavior of this species in its U.S. range. I used hard parts in 305 seal scats and 49 stomachs, and fatty acid profiles in 45 seal blubber cores, to 1) reconstruct the diet of gray seals in U.S. waters, and 2) investigate regional, temporal, and intraspecific variation in the diet. I compared species in the diet with those most abundant in the seals' range, as measured by bottom trawl surveys. I analyzed the tracks of 6 satellite-tagged seals, and asked which prey species were most abundant in areas where foraging activity occurred. I recovered a total of 3,798 otoliths, and 7,005 prey individuals from 34 prey taxa. Sand lance (Ammodytes spp.) dominated the diet by weight (53.3% of total) and number (66.3% of total). Sand lance, winter flounder (Pseudopleuronectes americanus), red/white hake (Urophycis spp.) and Atlantic cod (Gadus morhua) together made up 82% of the diet by weight. Cod comprised 6.4% of the diet by weight, although this varied seasonally. Fatty acid profiles were best able to classify seals by age (young-of-the-year pups vs. yearlings, Wilks-Lambda = 0.27, F25,19 = 2.07, p <0.054), suggesting that diet differences were most pronounced between these two groups. Consistent 2:1 ratios of 22:6n3 and 20:5n3 fatty acids occurred in seal blubber (10.12/5.00 = 2.02). These ratios are similar to those in smooth skate (Malacoraja senta, 20.87/10.02 = 2.08) and alewife (Alosa pseudoharengus, 15.04/7.48 = 2.01), indicating that these species were important in the diet. Seals consumed abundant species, and tracked interannual trends in sand lance abundance, but the diet could not be predicted from prey availability alone. Satellite telemetry of seals revealed area restricted search behavior and central place foraging activity in areas with high abundance of sand lance and winter flounder, and these taxa comprised over 72% of the diet estimated from scats.
ACCESS TO URBAN FOOD OUTLETS AS A PREDICTOR OF DIABETES
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Earth & Environmental Sciences
Background and problem statement:There is an unprecedented rise in diabetes in urban populations worldwide. A relationship between spatial concentration of other metabolic diseases and poor access to healthy foods in some underserved urban neighborhoods have been reported. Concurrently, a relationship between increased risk of developing diabetes and consumption of unhealthy foods and has been shown to exist. Neighborhood food contexts hypothesized to lead to developing diabetes need to be studied. Study goals:: The main hypothesis of this study is that the degree of access to food outlets near residences influences the outcome of diabetes. Covariates include individual-level variables of age and gender of the subjects, and neighborhood-level variables of educational attainment, percent of residents in poverty, of housing units without vehicles, and of female-headed households with children. Methods:Address, demographic, and health data extracted from medical records of black visitors to hospital emergency department were linked to geo-referenced socio-economic and food outlet data for the visitors' Census Tract (CT) of residence. Hierarchical linear modeling was used to consider the effect of variation in food and socio-economic environments on diabetes among the subjects. A cross-sectional study was designed and a multilevel logistic regression analysis was performed. Results: Spatial access to food outlets was not a significant predictor of diabetes in this study. However, subjects living in the socio-economically deprived neighborhoods had a higher probability of having diabetes. For every unit decrease in the neighborhood's socio-economic index constructed from the census variables, the subjects were 7 percent more likely to have diabetes (CI 1.03-1.12, p-value 0.0024). Female gender and older age were strongly associated with odds of having diabetes. Conclusions: Socio-economic context of neighborhood was shown to affect probability of having diabetes, while local food outlet access did not. The results indicate that there may be a critical difference between economic and spatial access to foods and the actual choices individuals make about their diets. These choices may be driven by individual cultural and social preferences. More research is needed to study these individual biosocial factors and to analyze how they affect diet and diabetes outcome.