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Causal Discovery For Relational Domains: Representation, Reasoning, And Learning, Marc Maier
Causal Discovery For Relational Domains: Representation, Reasoning, And Learning, Marc Maier
Doctoral Dissertations
Many domains are currently experiencing the growing trend to record and analyze massive, observational data sets with increasing complexity. A commonly made claim is that these data sets hold potential to transform their corresponding domains by providing previously unknown or unexpected explanations and enabling informed decision-making. However, only knowledge of the underlying causal generative process, as opposed to knowledge of associational patterns, can support such tasks. Most methods for traditional causal discovery—the development of algorithms that learn causal structure from observational data—are restricted to representations that require limiting assumptions on the form of the data. Causal discovery has almost exclusively …
Physiological Models Of Geobacter Sulfurreducens And Desulfobacter Postgatei To Understand Uranium Remediation In Subsurface Systems, Roberto Orellana
Physiological Models Of Geobacter Sulfurreducens And Desulfobacter Postgatei To Understand Uranium Remediation In Subsurface Systems, Roberto Orellana
Doctoral Dissertations
Geobacter species are often the predominant Fe(III)-reducing microorganisms in many sedimentary environments due to their capacity for extracellular electron transfer. This exceptional physiological capability allows them to couple acetate oxidation to uranium (U(VI)) reduction, that is one of the most significant interactions between radionuclides and microorganisms that naturally takes place in uranium-contaminated environments. Although this process has been proposed as a promising strategy for the in situ bioremediation of uranium-contaminated groundwater, little is known about the molecular mechanisms involved in U(VI) reduction and the interaction between Geobacter and other microbial species. In the first two research chapters, this dissertation aim …
Evaluating Effects Of Molecular Heterogeneity On The Non-Linear Mechanical Behavior Of Epoxy Networks, Zhan Hang Yang
Evaluating Effects Of Molecular Heterogeneity On The Non-Linear Mechanical Behavior Of Epoxy Networks, Zhan Hang Yang
Doctoral Dissertations
This thesis describes synthetic and processing strategies to formulate epoxies resins with molecular heterogeneity to achieve enhanced engineering properties. The network heterogeneities include chemical differences in stiffness and crosslink density, as well as mechanical difference in baseline energy state. The focus is to understand the fundamental structure-process-property relationships in these unusual network polymers, especially the post-yield responses and fracture toughness. The main characterization techniques to probe the complex network architectures are dynamic mechanical spectroscopy and compression tests. Ductility and governing parameters are also proposed to describe the relationships between molecular structures and physical properties. Three different staged fabrication strategies are …
Environmental Change And The Agro-Pastoralist Livelihood In The Andes Of Peru, Meagan M. Mazzarino
Environmental Change And The Agro-Pastoralist Livelihood In The Andes Of Peru, Meagan M. Mazzarino
Doctoral Dissertations
This dissertation research focuses on a high elevation Andean social-ecological system. It examines system linkages between climate, grazing pasture (wetlands), and agro-pastoralist livelihood strategies in an indigenous peasant community. Working within the conceptual framework of complex systems dynamics and sustainable livelihoods analysis, methods and concepts are synthesized from the disciplines of climatology, hydrology, remote sensing and political ecology, and results contribute to the transdisciplinary literature on vulnerability analysis within the context of environmental change. In the Andes of southern Peru livelihoods are based on agro-pastoralist activities that rely on access to natural resources in the puna ecosystem. The majority of …
The Oirad Of The Early 17th Century: Statehood And Political Ideology, Richard P. Taupier
The Oirad Of The Early 17th Century: Statehood And Political Ideology, Richard P. Taupier
Doctoral Dissertations
The early 17th century Oirad ulus represents a major turning point in the politics that dominated Central Asian during the second millennia. The Oirad rose among nomadic and settled states to take control of the Central Asian steppes and play an instrumental role as the modern world was taking shape. Following several major studies of the 17th century Oirad over the past twenty years some fundamental issues remain unresolved. One key issue is the political status of the early 17th century Oirad. Confusions arise from conflicting sources and the absence of Oirat primary texts as well as from narratives influenced …
The Massachusetts Educator Evaluation Framework And Transformational Leadership Alignment: An Investigation, Martin J. Mcevoy Jr
The Massachusetts Educator Evaluation Framework And Transformational Leadership Alignment: An Investigation, Martin J. Mcevoy Jr
Doctoral Dissertations
The recent Massachusetts Educator Evaluation Regulations (CMR 35.00) articulates goals that include growth and improved performance by teachers. Despite this stated goal, however, it is unclear if the policy is consistent with transformational leadership, which has shown correlation with growth and performance. In fact, the policy may instead bring about unintended consequences associated by some with evaluations in general, such as promoting “inspectional and fault finding supervision . . . [that] has serious consequences for the improvement of teaching and student achievement” (Glanz, 2005, p. 3). Through a discursive analysis of the Educator Evaluation Regulations (CMR 35.00) and semi-structured interviews …
Mind, Brain, And Education: A Case Study Of Student Perceptions Of An Interdisciplinary Graduate Program, Martha C. Lees
Mind, Brain, And Education: A Case Study Of Student Perceptions Of An Interdisciplinary Graduate Program, Martha C. Lees
Doctoral Dissertations
Advances in developmental and neuroscience research, calls for educational reform, and an emphasis on interdisciplinarity have generated interest in how science might inform educational practice and policy, resulting in the emerging field of mind, brain, and education (MBE). A primary goal of the field is to connect the cognitive and developmental sciences, biology, and education to develop a scientific grounding for educational practice and policy. Interdisciplinary MBE graduate programs seek to train a new generation of interdisciplinary researchers and practitioners. The purpose of this case study is to investigate students’ perceptions of their experiences developing interdisciplinary understanding in an MBE …
Engineered Nanoparticles For Detection And Treatment Of Bacteria And Biofilms, Xiaoning Li
Engineered Nanoparticles For Detection And Treatment Of Bacteria And Biofilms, Xiaoning Li
Doctoral Dissertations
Rapid and sensitive detection and identification of bacteria woud control and prevent bacterial infection and disease, enhancing the likelihood of early diagnosis and treatment. Especially developing effective biosensor for identification of bacteria species involved in formation of biofilms, which cause chronic and persistent diseases, would promote diagnostic and therapeutic efficiency. Conventional detection methods are limited by sensitivity and required time. First part of my research has been focused on developing a rapid, simple, and sensitive biosensor aiming at portable device application for detection of bacteria in water samples. This sensor is able to detect bacteria at low concentration and generate …
The Impact Of Television Program Diet On Children's Achievement, Heather J. Lavigne
The Impact Of Television Program Diet On Children's Achievement, Heather J. Lavigne
Doctoral Dissertations
In this study, three waves of data from the Panel Study of Income Dynamics’s Child Development Supplement were used to examine patterns of children’s early TV exposure and its influence on middle childhood and adolescence. Analyses examined the pathways of influence depending on whether a dosage (hours of exposure) or diet (proportion of content to total TV time) variable was used. Results revealed that, in a dosage model, violent hours of early TV exposure were associated with decreases in independent reading and increases in externalizing behavior problems, but these did not predict later achievement. Early educational TV amount of exposure …
Functional Nanocomposites From Self-Assembly Of Block Copolymers With Nanoparticles, Xinyu Wang
Functional Nanocomposites From Self-Assembly Of Block Copolymers With Nanoparticles, Xinyu Wang
Doctoral Dissertations
This dissertation studied the proper distribution and location control of nanoparticles (NPs) within block copolymer (BCP) templates. A facile ligand exchange reaction was introduced for the hydrophilic magnetic NPs (MNPs) that are readily dispersed in polar solvents with outstanding stability. Small molecule ligands were selected to associate strongly with particle surfaces, provide hydrophilic termini for polarity matching with polar solvents, and offer the potential for hydrogen-bonding interactions to facilitate NP incorporation into polymers. Areal ligand densities of NPs indicated a significant increase in the ligand coverage after the exchange reaction. Hydrophilic MNPs were shown to drive the self-assembly of BCPs …
Single Molecule Studies Of A Short Rna, Peker Milas
Single Molecule Studies Of A Short Rna, Peker Milas
Doctoral Dissertations
The material related with orientation of Cyanine dyes and their behavior at the ends of duplex RNA is also documented in [110]. Cyanine dyes are widely used to study the folding and structural transformations of nucleic acids using fluorescence resonance energy transfer (FRET). The extent to which FRET can be used to extract inter- and intra-molecular distances has been the subject of considerable debate in the literature; the contribution of dye and linker dynamics to the observed FRET signal is particularly troublesome. We used molecular dynamics (MD) simulations to study the dynamics of the indocarbocyanine dyes Cy3 and Cy5 attached …
Understanding Income Inequality In The United States, Mark J. Stelzner
Understanding Income Inequality In The United States, Mark J. Stelzner
Doctoral Dissertations
In a democracy where the median income is substantially less than the mean, why does the poor majority not implement a significant level of redistribution? Despite fears that democracy would empower the poor majority to such ends, constituents of below average income have a mixed record of utilizing democracy to ameliorate economic inequality in the United States. How do we understand this puzzle? Why does the poor majority not maintain a constant level of redistribution in a democracy? In the first part of my dissertation, I provide a game theoretic answer based on historical research which is in accord with …
Cognitive Malleability: Does Disgust Act As A "Stop" Signal On Currently Accessible Cognitive Processing Styles In Perceptual And Conceptual Tasks?, Elicia C. Lair
Doctoral Dissertations
Much of the research on feeling and thought supports the notion of a fixed relationship between affect and cognition, specifically that particular affective experiences promote particular ways of thinking (i.e., information processing styles). Surprisingly, little is known about the relationship between disgust and cognition, and this dissertation sought to rectify this omission. The recently proposed Cognitive Malleability approach (Clore, et al., 2001; Huntsinger & Clore, 2007; Isbell, 2010; Isbell, Lair, & Rovenpor, 2013) calls the fixed nature of the affect-cognition relationship into question, and instead argues that affect confers value on whatever information processing style is currently dominant. This new …
Interrogating The Divide: A Case Study Of Student Technology Use In A One-To-One Laptop School, Nicholas Wilson
Interrogating The Divide: A Case Study Of Student Technology Use In A One-To-One Laptop School, Nicholas Wilson
Doctoral Dissertations
Persistent gaps in technology literacy skills between students of differing socioeconomic backgrounds over the past two decades (even despite cases of parity in technology resources (Subramony, 2007) amongst poor and affluent students) have necessitated that researchers now look beyond monetary funding as the primary reason for the existence of the Digital Divide. Rather than looking to quantitative measures of students’ technology skills to identify potential areas for skill remediation or special services, some scholars have adopted a sociocultural approach to the problem to examine how the circumstances of technology-related classroom activities influence teachers’ technology integration strategies, and the ways in …
Inference-Based Forensics For Extracting Information From Diverse Sources, Robert J. Walls
Inference-Based Forensics For Extracting Information From Diverse Sources, Robert J. Walls
Doctoral Dissertations
Digital forensics is tasked with the examination and extraction of evidence from a diverse set of devices and information sources. While digital forensics has long been synonymous with file recovery, this label no longer adequately describes the science’s role in modern investigations. Spurred by evolving technologies and online crime, law enforcement is shifting the focus of digital forensics from its traditional role in the final stages of an investigation to assisting investigators in the earliest phases — often before a suspect has been identified and a warrant served. Investigators need new forensic techniques to investigate online crimes, such as child …
Flexible Tethers In Multi-Chromophoric Systems: Linking Photophysics With Assembly, Jeffrey M. Lucas
Flexible Tethers In Multi-Chromophoric Systems: Linking Photophysics With Assembly, Jeffrey M. Lucas
Doctoral Dissertations
Aggregation and folding events in conjugated polymers have a dramatic effect on the photophysics, and in turn, the efficiency of said species in organic electronic devices. The factors that lead to twisting, bending and folding in conjugated polymers have been studied in numerous polymeric materials, but due to the variability of these events, they remain poorly understood. To probe the spectroscopic signatures of folding and to link them with conformational and morphological features formed by these species in the solid state, a series of alternating co-polymers were then synthesized, incorporating the 2- and 4-carbon tethers with oligo-phenylenevinylene derivatives. Static absorption, …
Polymer Modification With Multifunctional Additives And Unique Processing Methods, Polina R. Ware
Polymer Modification With Multifunctional Additives And Unique Processing Methods, Polina R. Ware
Doctoral Dissertations
This dissertation describes the investigation of unconventional methods to enhance polymer properties either by using unique processing methods, such as solid-state deformation, or by using multifunctional additives that can simultaneously provide a number of property enhancements. The three main research areas of this dissertation are self-reinforced glassy thermosets, melt-processeable organic/inorganic thermoplastic elastomers and semi-crystalline thermoplastics with improved ductility due to a unique solid-state process treatment. Various thermosets, including epoxies, are used in systems with fibers or other additives to improve stiffness. However such systems are difficult to process due to increased viscosity. This work investigates a new method to reinforce …
Efficient Routing And Scheduling In Wireless Networks, Anand Seetharam
Efficient Routing And Scheduling In Wireless Networks, Anand Seetharam
Doctoral Dissertations
The temporal and spatial variation in wireless channel conditions, node mobility make it challenging to design protocols for wireless networks. In this thesis, we design efficient routing and scheduling algorithms which adapt to changing network conditions caused by varying link quality or node mobility to improve user-level performance. We design and analyze routing protocols for static, mobile and heterogeneous wireless networks. We analyze the performance of opportunistic and cooperative forwarding in static mesh networks showing that opportunism outperforms cooperation; we identify interference as the main cause for mitigating the potential gains achievable with cooperative forwarding. For mobile networks, we quantitatively …
Formación De Intérpretes Y Políticas Lingüísticas En La Provincia Jesuítica Del Paraguay (S. Xvii - Xviii), Ana P. Rona
Formación De Intérpretes Y Políticas Lingüísticas En La Provincia Jesuítica Del Paraguay (S. Xvii - Xviii), Ana P. Rona
Doctoral Dissertations
This dissertation explores language policies regarding selection and training of interpreters by the Society of Jesus during 17th and 18th centuries, in the former Paraquaria (the Jesuit Province of Paraguay). The Society of Jesus played a major role in the standardization of indigenous languages, as well as in translation and education policies; all areas of what is now known as language planning. Using as primary sources public and private letters produced by Jesuit authorities during this period, this study identifies overt and covert (Schiffman, 1996) language policies regarding interpreters, their linguistic repertories and the quality of their work. …
Fragments And Clausal Ellipsis, Andrew Weir
Fragments And Clausal Ellipsis, Andrew Weir
Doctoral Dissertations
This dissertation investigates the syntactic and semantic properties of fragments -- utterances which consist of a constituent smaller than a clause. Examples include short answers, such as What did he eat? --- Chips, as well as cases which do not respond to any overt question; for example, saying The train station, please on entering a taxi. I defend Merchant 2004's proposal that, underlyingly, fragments contain clausal structure: the fragment answer chips is elliptical for he ate chips, with he ate being present in the syntax but unspoken. I argue that challenges to ellipsis-based accounts of fragments can be …
Introducing The Newton-Poisson-Brillouin Model In The Quest For Plasmons In Metallic Carbon Nanotubes, Richard P. Zannoni
Introducing The Newton-Poisson-Brillouin Model In The Quest For Plasmons In Metallic Carbon Nanotubes, Richard P. Zannoni
Doctoral Dissertations
A new method is presented to model carbon nanotubes (CNT) of micron length. The Newton-Poisson-Brillouin (NPB) model uses Newtonian physics to model the interaction of a population of thermally excited quasi-particles. The NPB model is self-consistent with Poisson’s equation, and the quasi-particles are confined to the CNT’s band structure. In this work, we explore the parameter space of the model.
Engineering Surface Functionality Of Nanoparticles For Biological Applications, Yi-Cheun Yeh
Engineering Surface Functionality Of Nanoparticles For Biological Applications, Yi-Cheun Yeh
Doctoral Dissertations
Engineering the surface functionality of nanomaterials is the key to investigate the interactions between nanomaterials and biomolecules for potent biological applications such as therapy, imaging and diagnostics. My research has been orientted to engineer both of the surface monolayers and core materials to fabricate surface-functionalized nanomaterials through the synergistic multidisciplinary approach that combine organic chemistry, materials science and biology. This thesis illustrates the design and synthesis of the surface-funcitonalized quantum dots (QDs) and gold nanoparticles (AuNPs) for the fundamental studies and practical applications. For QDs, A new class of cationic QDs with quaternary ammonium derivatives was synthesized to provide permanent …
Production Of Sustainable Aromatics From Biorenewable Furans, Christopher Luke Williams
Production Of Sustainable Aromatics From Biorenewable Furans, Christopher Luke Williams
Doctoral Dissertations
Increasing demand for renewable and domestic energy and materials has led to an accelerated research effort in developing biomass-derived fuels and chemicals. The North American shale gas revolution can provide a domestic source for the manufacture of four of the five major products of the world chemical industry: methanol, ethylene, ammonia, and propylene. However this emerging domestic resource lacks a conversion pathway to the fifth major chemical building block; the larger C6 aromatics benzene, toluene, and xylene (BTX). One sustainable feedstock for renewable C6 aromatic chemicals is sugars produced by the saccharification of biopolymers (e.g., cellulose, hemicellulose). The catalytic conversion …
A Journal Club: A Scholarly Community For Preservice And Inservice Science Teachers, Karen Tallman
A Journal Club: A Scholarly Community For Preservice And Inservice Science Teachers, Karen Tallman
Doctoral Dissertations
This qualitative case study examines how a journal club can be used as a pedagogical tool in science teacher education. Six preservice and inservice science teachers, for seven months, participated in a journal club where they chose, read, and discussed science education research articles from problems or concerns they had in their teaching practice. The data included field notes, audio-recordings of meetings, pre- and post- interviews with all the teachers, two focus groups, artifacts collected (e.g. journal articles, reflective paper, e-mail exchanges, and researcher’s field notes). The data were analyzed using the techniques of grounded theory (Corbin & Strauss, 2008). …
Elucidating Cellular Signaling Pathways That Contribute To The Immunopathogenesis Of Aplastic Anemia, Christina M. Kuksin
Elucidating Cellular Signaling Pathways That Contribute To The Immunopathogenesis Of Aplastic Anemia, Christina M. Kuksin
Doctoral Dissertations
Aplastic Anemia is a rare immune mediated bone marrow failure disease that is mediated by autoreactive T cells that cause destruction to the stem, progenitor, and stromal cells in the bone marrow. Because little is known about the etiology of the disease, our lab has developed a major MHC mismatch GVHD model to examine cellular pathways in autoreactive T cells that contribute to disease. We examined three pathways that are important in T cell activation and differentiation and asked if they were important in the development of Aplastic Anemia. First, we were able to show that expression of active PKCθ …
Relational Coordination: The Perception And Experiences Of Student Nurses And Nursing Faculty In A Hospital Setting, Clare Lamontagne
Relational Coordination: The Perception And Experiences Of Student Nurses And Nursing Faculty In A Hospital Setting, Clare Lamontagne
Doctoral Dissertations
The purpose of this study was to describe and measure student nurses’ and nursing faculty experiences and perceptions of relational coordination during their most recent clinical experience in a hospital setting. The complexity of healthcare settings in the United States necessitates a coordinated approach to patient care in order to meet the divergent needs of its citizens. Healthcare students and professionals need to be prepared to work collaboratively and communicate proficiently and effectively. The theory of relational coordination states that, in a well-functioning organization, members of the healthcare team engage in frequent, timely, accurate, and problem-solving communication and have high …
Signal Processing In Wireless Communications: Device Fingerprinting And Wide-Band Interference Rejection, Adam C. Polak
Signal Processing In Wireless Communications: Device Fingerprinting And Wide-Band Interference Rejection, Adam C. Polak
Doctoral Dissertations
The rapid progress of wireless communication technologies that has taken place in recent years has significantly improved the quality of everyday life. However with this expansion of wireless communication systems come significant security threats and significant technological challenges, both of which are due to the fact that the communication medium is shared. The ubiquity of open wireless Internet access networks creates a new avenue for cyber-criminals to impersonate and act in an unauthorized way. The increasing number of deployed wide-band wireless communication systems entails technological challenges for effective utilization of the shared medium, which implies the need for advanced interference …
Financialization Of The Commodities Futures Markets And Its Effects On Prices, Manisha Pradhananga
Financialization Of The Commodities Futures Markets And Its Effects On Prices, Manisha Pradhananga
Doctoral Dissertations
After declining for almost three decades, the food price index of the Food and Agricultural Organization (FAO) rose by 90 percent between January 2002 and June 2008. Besides the magnitude, the rise in prices was remarkable for its breadth, affecting a broad range of commodities including agricultural (wheat, corn, soybeans, cocoa, coffee), energy (crude oil, gasoline), and metals (copper, aluminum). According to the US Department of Agriculture, this price spike was responsible for increasing the number of malnourished people by 80 million. These dramatic developments in prices coincided with a rapid inflow of investment into the commodities futures market -- …
Patterning And Mechanical Analysis Of Fiber-Based Materials, Samuel A. Pendergraph
Patterning And Mechanical Analysis Of Fiber-Based Materials, Samuel A. Pendergraph
Doctoral Dissertations
The ability to define and control the topography of a surface has been studied extensively due to its importance in a wide variety of applications. The control of a non-planar topography would be very valuable since a number of structures that are pervasive in artificial applications (e.g. fibers, lenses) are curved interfaces. This potential of enabling applications that incorporate non-planar geometries was the motivation for this thesis. The first study of this thesis comprises the study of patterning the circumference of micrometer sized fibers. Specifically, a unique technique was described to pattern the fiber with a periodic array of colloids. …
How Much Do In-Vehicle Tasks With Swapping, Switching And Spillover Effects Interfere With Drivers’ Ability To Detect And Respond To Threats On The Forward Roadway?, Siby Samuel
Doctoral Dissertations
Distractions have long been associated with crashes. A review of the literature shows drivers engaging in secondary tasks to be three times as likely to crash as compared to attentive drivers. Although several studies report that excessively long glances away from the forward roadway elevate the risk of crashes, little research has been conducted to determine how long a driver needs to glance towards the forward roadway in between glances inside the vehicle to perform a secondary task in order to detect threats present in or emerging from the forward roadway. To determine this, drivers were asked to perform simulated …