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I. Incorporation Of Functionality At The Β-Position For The Zinc-Mediated Chain Extension Reaction Ii. Formal Synthesis Of Heliotridane And Pseudoheliotridane Through A Zinc-Mediated Chain Extension Approach, Nicholas Alexander Arnista

Doctoral Dissertations

The zinc-mediated chain extension reaction has been previously developed to incorporate alkyl or aryl substituents at the β position of the chain-extended product. The incorporation of heteroatom functionality at the β position of the chain-extended product was demonstrated through the use of a functionalized zinc carbenoid species. Silyl ether-functionalized geminal diiodides were used in the chain extension reaction with low to modest yields. Optimization of the chain extension reaction was performed by modification of solvent, reaction temperature, reaction time, and addition of diiodide. The chain extension reaction was performed on several different substrates, such as β-keto esters, β-keto amides, and …

Primary Cilia In The Pathogenic Mouse Brain & Eeg Waveform Analysis Of A Mouse Model Of Alzheimer's Disease, Ashley Diemand Sterpka

Doctoral Dissertations

In the last two decades, primary cilia have become recognized as tiny sensory organelles with considerable physiological function including regulation of cell division and modulation of transduction pathways. Scientists build on former discoveries, identifying new connections and accentuating the value of primary cilia in disease and intercellular signaling. Astrocytes, the most numerous cell type within the brain, act in support of neurons and maintain neurological health by providing neurotrophic factors and removing synaptic debris. These cells are particularly significant in reparations following neural injury and diseases, altering shape and function to protect healthy tissue. Astrocytes display primary cilia, yet little …

Climatic And Biotic Interactions In Terrestrial Systems During Ancient Warm Periods, Sarah Johnson Widlansky

Doctoral Dissertations

This work focuses on two terrestrial sedimentary records in the western United States that record the ancient greenhouse interval of the early Paleogene (~ 55 million years ago). The Paleogene, and past warm periods in general, offer a means of understanding potential biotic and environmental response to future warming scenarios. Part One of this dissertation establishes a new stable isotope climate record from the Bighorn Basin of Wyoming that is tied to an extensive fossil mammal assemblage (Chapter 1). This new stable isotope record captures carbon isotope excursions (CIEs) associated with the early Eocene hyperthermals ETM2, H2, and potentially I1 …

Heat Transport By Baroclinic Acoustic Streaming, Jacques Abdul Massih

Doctoral Dissertations

Acoustic streaming refers to time-averaged flows generated by time-periodic sound waves. In classic“Rayleigh streaming”, the mean flow is generated by the interaction of a standing acoustic wave with a solid boundary (e.g., a channel wall). Applications of acoustic streaming include inducing fluid mixing in microfluidic medical devices, improving the efficiency of chemical reactions, and enhancing heat transfer. Recently, Chini et al. [J. Fluid Mech., Vol. 744 (2014)] and Michel & Chini [J. Fluid Mech., Vol. 858 (2019)] demonstrated that strong acoustic streaming flows can be generated in gases subjected to an imposed cross-channel temperature gradient. In contrast with Rayleigh streaming, …

First-Generation Student Status As A Predictor Of Participation In Selected High-Impact Practices At The University Of New Hampshire, Paula Marie Dinardo

Doctoral Dissertations

Institutions of higher education are under increased scrutiny as graduation rates decline while student loan debt soars. One proposed strategy to improve completion rates is to give additional support to those students who are most at-risk of leaving college before graduating. Research has shown that first-generation students are more likely to leave college before attaining a degree than their non-first-generation counterparts.

Research has also suggested that engaging in two or more High-Impact Practices (or HIPs) during college can improve one’s academic achievement and persistence to graduation. HIPs are defined as educationally purposeful activities that require students to delve deeply into …

Penalized Regression Splines-Based Tests For Comparing Two Time Series With Unequal Lengths, Mirajul Islam

Doctoral Dissertations

The Spline-based modeling has been an established tool for parametric and nonparametricregression modeling because of its continuous progress on theoretical and computational fronts over the last three decades. This thesis explores the idea of penalized spline modeling and goodness of fit testing in the context of time series testing in the frequency domain approach. The comparison of different time series is an important topic in statistical data analysis and has various applications in scientific research. One approach to identifying similarities or dissimilarities between two stationary processes is to compare the spectral densities of both time series. This thesis examines whether …

Efficient Data-Driven Robust Policies For Reinforcement Learning, Bahram Behzadian

Doctoral Dissertations

Applying the reinforcement learning methodology to domains that involve risky decisions like medicine or robotics requires high confidence in the performance of a policy before its deployment. Markov Decision Processes (MDPs) have served as a well-established model in reinforcement learning (RL). An MDP model assumes that the exact transitional probabilities and rewards are available. However, in most cases, these parameters are unknown and are typically estimated from data, which are inherently prone to errors. Consequently, due to such statistical errors, the resulting computed policy's actual performance is often different from the designer's expectation. In this context, practitioners can either be …

N-Heterocyclic Carbene Functionalized Single-Chain Nanopartcles Aqueous Catalytic Platform, Xianggeng Liu

Doctoral Dissertations

Single-chain nanoparticles (SCNP) are a class of intramolecular cross-linked polymericnanoparticles with a variety of applications including catalysis, sensors, nanomedicine, and nanoreactors. Such nanoparticles are synthesized by folding or collapsing single polymer molecules. By implementing a single-chain folding technique, the single-chain nanoparticles with uniform degrees of cross-linking are synthesized by parent polymer chains with similar chain lengths and polymer microstructure. Polymer chains that are synthesized by various controlled polymerization techniques can be converted to SCNPs through a variety of covalent chemistry and supramolecular interactions. Based on the expected cross-linking chemistry, related functional groups can be installed either during monomer synthesis or …

Recombination Drives Genomic Divergence And Cooperation Across Bacterial Populations, Isaiah Paolo Atienza Lee

Doctoral Dissertations

Genetic recombination is a major driving evolutionary force across the Tree of Life, but it plays a special role in bacteria. In the absence of sexual reproduction, bacteria rely on horizontal transmission to recombine their genetic material. Horizontally transferred genes can spread rapidly across a population, greatly expanding the niches available to bacteria. We are only beginning to understand the degree to which recombination varies between and even within bacterial taxa. In the first part of this dissertation (Chapter 1 and Chapter 2), I investigate how patterns of recombination influence bacterial diversity. In Chapter 1, I studied the pan-genome of …

Sociocultural Dimensions Of Environmental Stewardship In New Hampshire: Implications For Adult Environmental Education, Ian Patrick Hanley

Doctoral Dissertations

The overarching aim of this dissertation is to expand evidence and theory of adult identity processes in the context of environmental stewardship, as well as to provide knowledge and recommendations to environmental stewardship and environmental education professionals. The intent is to better understand variation in how adult environmental stewards report on and value their own engagement with both sociocultural and natural systems. This line of inquiry stems from the fundamental claim that environmental stewardship activity is not singularly based on environmental content knowledge but is also related to forms of cultural and social engagement. By recognizing these dual aspects of …

Socioscientific Decision-Making In Undergraduate Students: The Role Of Personal Epistemology, Jordan Dana Bader

Doctoral Dissertations

Socioscientific issues (SSIs), or controversial scientific issues with social implications, influence members of society regardless of demographic. SSIs are contentious and ill-structured, meaning they do not have a definitive answer. To properly equip students with the tools needed to handle SSIs, undergraduate science curricula emphasize scientific literacy skills, such as the ability to search, recognize, and utilize accurate scientific information when handling science driven issues outside of the classroom. However, SSIs are influenced by political, social, economic, and cultural stakeholders. Therefore, students may not be basing their SSI decisions off of accurate information. An individual’s personal epistemology is known to …

Water Droplet Machining And Droplet Impact Mechanics, Benjamin Mitchell

Doctoral Dissertations

Water Droplet Machining (WDM) is a new manufacturing process, which uses a series of high-velocity, pure-water droplets to impact and erode metal workpieces, for the purpose of through-cutting, milling and surface profiling. The process is conducted within a vacuum environment to suppress aerodynamic drag and atomization of the waterjet and droplet stream. This preserves droplet momentum and allows for a more efficient transfer of energy between the water and workpiece, than in standard atmospheric pressure. As a new manufacturing technique, parameter-specific details and characteristics of this process are absent from the scientific literature. Furthermore, the erosion mechanisms involved in droplet-solid …

Structural And Biochemical Characterization Of The Allosteric Regulation Of Photoreceptor Phosphodiesterase, Richa Garg

Doctoral Dissertations

ABSTRACT

Structural and Biochemical Characterization of the Allosteric Regulation of Photoreceptor Phosphodiesteraseby Richa Garg

The photoreceptor phosphodiesterase (PDE6) is the central enzyme in the visual signaling pathway. Cone PDE6 is a homodimer consisting of a catalytic dimer (Pα’α’) and two cone-specific inhibitory γ-subunits (Pγ’). Rod PDE6 is a heterotetramer which consists of a catalytic dimer (Pαβ) with two rod-specific Pγ subunits. The PDE6 differs from other phosphodiesterases (PDEs), in its unique inhibitory Pγ subunit and its activation by α-subunit of the G-protein (Gα). Regulation of PDE6 activity is a key factor in determining the electric response upon light stimulations. PDE6 …

Melanin Pigments As Antibacterial Agents, Tahmineh Rahmani Eliato

Doctoral Dissertations

In this dissertation I investigated the structural properties of melanin biopigment from different sources as an antibacterial and endotoxin bonding agent. I extracted melanin from Equus ferus hair with acid hydrolysis (termed EquusMel) and characterized it by microscopic and spectroscopic techniques. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed that EquusMel is mainly elliptical in shape with a mesoporous and layered structure within the individual particles. Wide-angle (WAXS) and small-angle (SAXS) X-ray scattering measurements demonstrated a semicrystalline multilayered structure with order spacing of 45.2 Å. Pore size distribution determined by the Barrett–Joyner–Halenda (BJH) method showed primary pores within …

“Test Run Or One And Done”: Gender Differences In Lgbtq+ Hookup Experiences, Della Burke

Doctoral Dissertations

This dissertation explores queer individuals’ participation within hookup culture, the goals and motivations of those taking part in queer hookup encounters, and the ways queer individuals make sense of their hookup experiences. I analyze data from 24 semi-structured qualitative in-person and online interviews to examine LGBTQ+-identified individuals’ experiences with queer hookup encounters. This dissertation offers several major contributions to the scholarship of LGBTQ+ hookup experiences. First, I find that participants talk about three discrete levels of intimacy: noncommittal hookups, “catching feelings,” and third, “real relationships” or emotional connections. Second, both men and women define hookups as noncommittal sexual encounters, but …

A Memory-Based Approach To Multiple Document Comprehension, Allison Sonia-Bolduc

Doctoral Dissertations

Multiple document (MD) comprehension is of growing interest in the Internet age, in which reading material is readily available from multiple sources. However, comprehension research has typically been dominated by studies investigating single documents (Bråten et al., 2019; McNamara & Magliano, 2009). This dissertation applies a memory-based approach traditionally used in research on single document comprehension to a MD context, with the goal of understanding the on-line processing and integration of information from multiple documents. Expository-style passages were created in which the first half contained information that was either consistent or inconsistent with a target sentence in the second half. …

Essays On The Effects Of Air Quality And Intra-Industry Trade On Labor Market Outcomes, Protika Bhattacharjee

Doctoral Dissertations

This dissertation examines the impacts of poor air quality and the rise of intra-industry trade on different labor market outcomes like migration, workings hours, and wages. This thesis contributes two distinct strands of literature, literature on air pollution focusing on the economic consequences of poor air quality, and international trade literature. The first two essays examine how a moderate level of air pollution can drive migration decisions and impact working hours in the United States. The third essay investigates the role of the rise in within industry trade on occupational wages in the United States. This dissertation aims to contribute …

Cryopreservation Studies Of An Antifreeze Protein From The Desert Beetle Anatolica Polita, Jonathan Sreter

Doctoral Dissertations

Antifreeze proteins (AFPs) are specialized evolutionary adaptations by certain cold climate organisms, including fish, plants, fungi, bacteria, and insects, to prevent cryo-injury. AFPs contribute to freeze resistance or tolerance by binding to the surface of ice crystals and preventing their growth, as well as inhibiting ice recrystallization (i.e., small crystals restructuring into large crystals) during large temperature fluctuations and constant sub-zero temperatures. AFPs have potential applications in cryopreservation and in the development of cryo-functional materials for medicine, the food industry, and agriculture. We investigated the ability of an antifreeze protein from the desert beetle Anatolica polita, ApAFP752, to confer cryoprotection …

Notes From The Underground: An Exploration Of Burying Beetle Thermal Ecology, Sound Production And Reception, And Brain Morphology., Michelle Ward

Doctoral Dissertations

In a climatically and structurally changing world, it is important to understand how different thermal and social environments influence the behavior and physiology of the pillars of terrestrial ecosystems: insects. In this dissertation, I explored how insects, specifically Nicrophorus beetles, respond to biotic and abiotic challenges. Through this research, I addressed 1) how daily fluctuations in temperature influence Nicrophorus americanus reproductive success, 2) the context in which breeding pairs use stridulation during carcass burial, and subsequently how inhibition of stridulation influences reproductive success, 3) if the clypeal membrane on Nicrophorus beetles has the physiological properties of a tympanum, and if …

Compound, Elemental, And Isotopic Perspectives On Mercury Mobilization During Thaw In A Discontinuous Permafrost Zone, Maria F. Fahnestock

Doctoral Dissertations

Arctic ecosystems are a major global sink for both carbon (C) and mercury (Hg), both of which are influenced by anthropogenic activities. The accelerated climate-change-induced warming documented in the Arctic has led to permafrost thaw resulting in landscape evolution from hydrological, vegetation and microbial shifts. All of these resulting changes have the potential to influence how Hg, a toxic contaminant, is mobilized and re-cycled in this ecosystem. In this body of work, I investigate patterns of Hg speciation, elemental abundances, and stable isotopes across the thaw gradient in a permafrost peatland and interconnected freshwater lakes in Abisko, Sweden to assess …

Othered Ambitions: The Conflation Of Villainy And Homosexuality In 20th Century American Media, Sherard Harrington

Doctoral Dissertations

This work sets out to examine the ways in which homosexuality and villainy have been conflated throughout the 20th Century in American media, and the ways in which that conflation has been reinforced and challenged. My observations about the villainous connotations of homosexuality hold despite the ways in which the boundaries of homosexuality have changed throughout the century. A homosexual is anyone who experiences romantic or amorous affection for someone who presents with the same gender presentation and/or who experiences attraction aversion for those who present with the opposite gender presentation. A villain breaks the law seeking to restructure society …

Query-Specific Subtopic Clustering In Response To Broad Queries, Sumanta Kashyapi

Doctoral Dissertations

Information Retrieval (IR) refers to obtaining valuable and relevant information from various sources in response to a specific information need. For the textual domain, the most common form of information sources is a collection of textual documents or text corpus. Depending on the scope of the information need, also referred to as the query, the relevant information can span a wide range of topical themes. Hence, the relevant information may often be scattered through multiple documents in the corpus, and each satisfies the information need to varying degrees. Traditional IR systems present the relevant set of documents in the form …

Interventions Towards Sustainable Watershed Management As Demonstrated By Hydrologic Simulation, Shan Zuidema

Doctoral Dissertations

Increasing population, changing climate, and on-going legacies of environmental mismanagement motivate our need for deeper understanding of the process and limits of adaptation towards sustainable management of water resources. Movements towards open-science and transdisciplinary research have enabled deeper assessments of the co-evolution of human society and changing landscapes. Policies and decisions enabling environmental restoration or sustainable resource use have been actively pursued for decades. The social barriers that prevent adaptations to succeed are deep and entrenched, but equally important are the physical barriers. Successful adaptations in water resource management need to explicitly consider the joint interactions of intervention magnitude, or …

Evaluation Of Curing Effects On Cold In-Place Recycled (Cir) Materials, Chibuike Ogbo

Doctoral Dissertations

Most cold In-place recycled (CIR) construction use asphalt emulsion or foamed asphalt with or without active fillers as a stabilizing agent. To ensure the CIR layer gains appreciable stiffness and strength to support traffic, the stabilizing agents have to undergo curing (to gradually develop strength). If traffic is allowed on the CIR layer before sufficient strength and structural capacity is gained, premature damage will occur. Lack of a fast and reliable procedure to determine the extent of in-situ curing significantly increases the risk of such damage. Present construction specifications rely on empirically based time recommendations to ensure sufficient curing. Current …

The Efficacy Of Response To Intervention On Academic Outcomes At The Secondary School Level In A New England School District, Kimberly Mcglinchey

Doctoral Dissertations

Educational policies and practices have had a long-standing emphasis of conducting incoming literacy screenings to determine who is at risk for school failure. Response to intervention (RTI) is an intervention program designed to deliver educational resources to students who fall below what is deemed an acceptable level of proficiency as viewed through the early screening process. The goal of the program is to provide early mitigation in order to catch students up to their peers, and to limit misidentification into special education. Studies have evaluated the success of the program in grades K-3 and shown mixed success. However, there was …

Rational Design And Synthesis Of Antifreeze-Protein Inspired Polymers For Anti-Icing Coatings And Cryopreservation Applications, Mohamamd Mousazadehkasin

Doctoral Dissertations

Certain organisms living in cold regions have adapted different strategies to survive in harshly cold temperatures. Some of them use freeze-avoiding strategies in which they can prevent freezing by controlling the concentration of sugars (et. sucrose, trehalose) or polyols (glycerol), regulation of the ice nucleator, and dehydration. Other organisms have adapted to this extremely cold condition by producing antifreeze (gly)proteins (AF(G)Ps) which exhibit ice recrystallization inhibition (IRI), thermal hysteresis activity (THA), and dynamic ice crystal shaping. These proteins discovered in Antarctic fish in 1960 for the first time have been reported in bacteria, fungi, insects, and plants. AF(G)Ps and their …

The Active Tail In The Mms Era: An Ion Perspective, Anthony Jason Rogers

Doctoral Dissertations

The Earth's magnetic field has a complex and dynamic relationship with the greater solar system. The solar wind and interplanetary magnetic field extend the influence of the Sun's atmosphere to the orbit of Earth and well beyond, carrying charged particles in a constant stream of varying density and velocity. These solar influences carry energy which interacts with every object they encounter, including the Earth and its magnetic field.

The primary mechanism for the energetic interaction and exchange of energy between the Earth's magnetic field and the solar wind is called Magnetic Reconnection, a process by which two opposing magnetic fields …

Nsu Huizenga College Of Business And Entrepreneurship 2022-2023 Graduate Catalog, Nova Southeastern University

Huizenga Postgraduate Course Catalogs

No abstract provided.

Understanding Appalachian Deaths Of Despair Through A Perspective Of Marxism And Intersectionality, Mackenzie Boughner

Undergraduate Honors Theses

Uneducated working-class individuals in the United States are dying from suicide, drug overdose, and alcoholic-related liver disease at unprecedented rates; a phenomenon economists Anne Case and Angus Deaton describe as deaths of despair. This paper focuses on deaths of despair in the Appalachian region, where mortality rates from these types of deaths are disproportionately higher than the rest of the country. Marxism and intersectionality are two philosophical frameworks that I will apply to Appalachian despair to test the adequacy of their explanatory power. By placing Marxism and intersectionality in the context of the data surrounding deaths of despair, I can …

Trial Practice And Procedure, John O'Shea Sullivan, Leesa M. Guarnotta

Mercer Law Review

The 2021 Survey period yielded decisions involving issues of first impression relating to federal trial practice and procedure in the United States Court of Appeals for the Eleventh Circuit. This Article analyzes recent trial practice developments in the Eleventh Circuit, including significant rulings in the areas of consumer debt collections, removal, jurisdiction and abstention, arbitration, and sanctions.