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Dissertations and Theses

2020

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Articles 31 - 60 of 63

Full-Text Articles in Physical Sciences and Mathematics

Optimized Xanthene-Based Probes For Pancreatic Cancer Imaging, Ian Ruramai Munhenzva May 2020

Optimized Xanthene-Based Probes For Pancreatic Cancer Imaging, Ian Ruramai Munhenzva

Dissertations and Theses

Pancreatic Ductal Adenocarcinoma (PDAC) is one of the deadliest human malignancies with an extremely poor 5-year survival rate of below 5%. Surgical resection is the most effective treatment of choice because chemotherapy and radiation therapy do not improve life expectancy. Residual tumor after PDAC surgery is common due to a lack of PDAC targeted intraoperative contrast agents to confirm clear margins.

Fluorescence imaging has the potential to improve surgery outcome and PDAC patients' survival rate via the use of highly PDAC-specific molecular probes to facilitate tumor identification. This thesis describes the application of a focused library of benzoxanthene fluorophores for …


Leveraging Model Flexibility And Deep Structure: Non-Parametric And Deep Models For Computer Vision Processes With Applications To Deep Model Compression, Anthony D. Rhodes May 2020

Leveraging Model Flexibility And Deep Structure: Non-Parametric And Deep Models For Computer Vision Processes With Applications To Deep Model Compression, Anthony D. Rhodes

Dissertations and Theses

My dissertation presents several new algorithms incorporating non-parametric and deep learning approaches for computer vision and related tasks, including object localization, object tracking and model compression. With respect to object localization, I introduce a method to perform active localization by modeling spatial and other relationships between objects in a coherent "visual situation" using a set of probability distributions. I further refine this approach with the Multipole Density Estimation with Importance Clustering (MIC-Situate) algorithm. Next, I formulate active, "situation" object search as a Bayesian optimization problem using Gaussian Processes. Using my Gaussian Process Context Situation Learning (GP-CL) algorithm, I demonstrate improved …


Smart Contract Vulnerabilities On The Ethereum Blockchain: A Current Perspective, Daniel Steven Connelly May 2020

Smart Contract Vulnerabilities On The Ethereum Blockchain: A Current Perspective, Daniel Steven Connelly

Dissertations and Theses

Ethereum is a unique offshoot of blockchain technologies that incorporates the use of what are called smart contracts or DApps -- small-sized programs that orchestrate financial transactions on the Ethereum blockchain. With this fairly new paradigm in blockchain, however, comes a host of security concerns and a track record that reveals a history of losses in the range of millions of dollars. Since Ethereum is a decentralized entity, these concerns are not allayed as they are in typical financial institutions. For example, there is no Federal Deposit Insurance Corporation (FDIC) to back the investors of these contracts from financial loss …


Archaeological Feature Identification Through Geochemical Analysis Of Arctic Sediments From The Cape Krusenstern National Monument, Northwest Alaska, Patrick William Reed Apr 2020

Archaeological Feature Identification Through Geochemical Analysis Of Arctic Sediments From The Cape Krusenstern National Monument, Northwest Alaska, Patrick William Reed

Dissertations and Theses

Identification and interpretation of archaeological phenomena is typically based on visual cues and the physical presence of "something archaeological," such as a diagnostic artifact, landscape modification, or structural element. Yet many archaeological features, i.e. the discrete archaeological deposits related to past human behavior, lack clear indicators of human activity that provides clues to the feature's origin. At the Cape Krusenstern beach ridge complex, located in northwest Alaska, ambiguous features, that could be natural or anthropogenic (vegetation anomalies), or are of unknown cultural function (indeterminate), comprise 60% of the identified features at the complex. These ambiguous features represent a large gap …


Finding Trends In Big City Health Issues With Data Visualization, Shridhar Kulkarni Apr 2020

Finding Trends In Big City Health Issues With Data Visualization, Shridhar Kulkarni

Dissertations and Theses

In recent years, data visualization has become one of the most effective tools to understand and identify unseen features of the large datasets available. An open source data set available for health issues for big cities across the United States was obtained. There are numerous indicators presented in the dataset including Demographics, Chronic Health Diseases, Social and Economic Factors, Food Safety, Mortality Rates, Cancer and Life Expectancy Rates. The dataset encompassed myriad of demographics as well as specific data for a number of US cities. The data was explored in different methods in Data points in terms of the demographic …


Unpacking The Process And Outcomes Of Ethical Markets: A Focus On Certified B Corporations, Renée Bogin Curtis Apr 2020

Unpacking The Process And Outcomes Of Ethical Markets: A Focus On Certified B Corporations, Renée Bogin Curtis

Dissertations and Theses

The growth in conscious consumption presents an opportunity to 1) better understand the potential outcomes of ethical market practices as a community-advocacy tool and 2) to consider potential policy considerations. The marketplace has increasingly become an arena for social action. This leads to the question of how can markets facilitate ethical business practices and community benefits? The recent rise of social benefit corporations warrants an evaluation of the outcomes of ethically-driven markets. Using a comparative research design and qualitative interview methods, this study examines certified Benefit Corporations (B Corps) in two selected cities: Philadelphia and Portland. Through interviews with B …


Perception Of Healthcare Providers On Mirror Therapy For Stroke, Dhwani Kamlesh Doshi Apr 2020

Perception Of Healthcare Providers On Mirror Therapy For Stroke, Dhwani Kamlesh Doshi

Dissertations and Theses

Stroke is a very important health problem faced worldwide with high mortality and incidence. The majority of stroke survivors suffer temporary or permanent disabilities of which hemiparesis is one of the most common. Hemiparesis makes it difficult for patients to perform their activities of daily living and often they have declining quality of life. Mirror therapy (MT) is a an inexpensive, easy and safe intervention which has been proven to be very effective to improve the motor function in hemiparetic stroke. Despite this, it is not often employed. Hence, the purpose of this study was to explore the awareness and …


Chronic Migraine: Role Of Cgrp Antagonists And Botox, Gabriella Hassan Apr 2020

Chronic Migraine: Role Of Cgrp Antagonists And Botox, Gabriella Hassan

Dissertations and Theses

Chronic migraine (CM) is characterized by the International Headache Society classification (ICHD-3) as headache that occurs for greater than or equal to 15 days a month, lasting 4 or more hours. For chronic migraine patients, the goal with prophylactic treatment is to prevent future attacks and reduce the migraine frequency and severity. OnabotulinumtoxinA is the most universally accepted medication for the treatment of chronic migraine; and if successful, reduces migraine frequency up to 50%. The goal of CGRP (Calcitonin-gene-related peptide) antagonists is to reduce the frequency of chronic migraines by targeting the CGRP protein that is elevated during a migraine …


Study Of Satisfaction Of Inpatient Discharge Based On Nurses’ Perceptions, Hong Lin Apr 2020

Study Of Satisfaction Of Inpatient Discharge Based On Nurses’ Perceptions, Hong Lin

Dissertations and Theses

Patient satisfaction plays an important role in providing quality health care, and discharge satisfaction is part of overall patient satisfaction since it reveals how patients feel about their stay. In this paper, we evaluated inpatient discharge satisfaction based on nurses’ perceptions. An anonymous survey was used to evaluate how satisfied the patients were when being discharged from the acute care hospital with survey questions answered by nurses who work on medical-surgical floors. Data was collected from the questionnaires and analyzed using Excel.


Towards Wide Implementation Of Dance Therapy In Mental Health, Pin-Wen Chou Apr 2020

Towards Wide Implementation Of Dance Therapy In Mental Health, Pin-Wen Chou

Dissertations and Theses

In recent years, Dance Movement Therapy (DMT) has been increasingly mentioned in the field of mental health counseling. Despite the progress of DMT in terms of studies showing its efficiency for various forms of mental health conditions such as depression and trauma, the implementation of DMT amongst mental health therapists is still not as widespread as other forms of therapies such as verbal and art therapies. In this project, we aim to determine the underlying causes of its low implementation by surveying a set of populations, specifically mental health patients, mental health therapists that do not specialize in dance/movement therapy, …


Workflow Critical Path: A Data-Oriented Path Metric For Holistic Hpc Workflows, Daniel D. Nguyen Mar 2020

Workflow Critical Path: A Data-Oriented Path Metric For Holistic Hpc Workflows, Daniel D. Nguyen

Dissertations and Theses

Optimizing scientific application performance in HPC environments is a complicated task which has motivated the development of many performance analysis tools over the past decades. These tools were designed to analyze the performance of a single parallel code using common approaches such as message passing (MPI), multithreading (OpenMP), acceleration (CUDA), or a hybrid approach. However, current trends in HPC such as the push to exascale, convergence with Big Data, and growing complexity of HPC applications and scientific workflows, have created gaps that these performance tools do not cover, particularly involving end-to-end data movement through an end-to-end HPC workflow comprising multiple …


Multiple Diagram Navigation, Hisham Benotman Mar 2020

Multiple Diagram Navigation, Hisham Benotman

Dissertations and Theses

Domain novices learning about a new subject can struggle to find their way in large collections. Typical searching and browsing tools are better utilized if users know what to search for or browse to. In this dissertation, we present Multiple Diagram Navigation (MDN) to assist domain novices by providing multiple overviews of the content matter using multiple diagrams. Rather than relying on specific types of visualizations, MDN superimposes any type of diagram or map over a collection of documents, allowing content providers to reveal interesting perspectives of their content. Domain novices can navigate through the content in an exploratory way …


Extensible Performance-Aware Runtime Integrity Measurement, Brian G. Delgado Mar 2020

Extensible Performance-Aware Runtime Integrity Measurement, Brian G. Delgado

Dissertations and Theses

Today's interconnected world consists of a broad set of online activities including banking, shopping, managing health records, and social media while relying heavily on servers to manage extensive sets of data. However, stealthy rootkit attacks on this infrastructure have placed these servers at risk. Security researchers have proposed using an existing x86 CPU mode called System Management Mode (SMM) to search for rootkits from a hardware-protected, isolated, and privileged location. SMM has broad visibility into operating system resources including memory regions and CPU registers. However, the use of SMM for runtime integrity measurement mechanisms (SMM-RIMMs) would significantly expand the amount …


Tending The Fire: Wildfire Risk Management At The Interface, Cody Randolph Evers Mar 2020

Tending The Fire: Wildfire Risk Management At The Interface, Cody Randolph Evers

Dissertations and Theses

Escalating loss from wildfire in the American West has made clear the need to rethink wildfire risk, including how such risks result from the unique interaction of social and natural dynamics within the wildland urban interface. Unfortunately, techniques for studying these interactions remain limited. The intent of this research is to address this gap. In each of four chapters, I examine different aspects of wildfire risk management through a coupled human-natural lens. I document how wildfire activity has shifted over three decades across forest and shrubland systems in the western US and connect these changes to the simultaneous growth in …


Detecting Geomorphic Change And Stream Channel Evolution On The Sandy River, Oregon, Using Lidar Following Dam Removal In 2007, Lowell Henry Anthony Mar 2020

Detecting Geomorphic Change And Stream Channel Evolution On The Sandy River, Oregon, Using Lidar Following Dam Removal In 2007, Lowell Henry Anthony

Dissertations and Theses

Following the removal of Marmot Dam on the Sandy River, Oregon, several Lidar flights were flown over the area of the former reservoir. The resultant sequential DEMs permitted calculation of reach-scale volumetric erosion and aggradation following dam removal. This allows for change detection across the entire affected reach of the former impoundment rather than just at several cross sections. In the first year there was a net loss of blank sediment in the dewatered reach. Subsequent flights show continued degradation of 145,649 m3 as well as aggradation of 6,232 m3. Sediment transport reached quasi-equilibrium in 2012 with …


Balancing Security, Performance And Deployability In Encrypted Search, David Joel Pouliot Mar 2020

Balancing Security, Performance And Deployability In Encrypted Search, David Joel Pouliot

Dissertations and Theses

Encryption is an important tool for protecting data, especially data stored in the cloud. However, standard encryption techniques prevent efficient search. Searchable encryption attempts to solve this issue, protecting the data while still providing search functionality. Retaining the ability to search comes at a cost of security, performance and/or utility.

An important practical aspect of utility is compatibility with legacy systems. Unfortunately, the efficient searchable encryption constructions that are compatible with these systems have been proven vulnerable to attack, even against weaker adversary models.

The goal of this work is to address this security problem inherent with efficient, legacy compatible …


Novel View Synthesis In Time And Space, Simon Niklaus Feb 2020

Novel View Synthesis In Time And Space, Simon Niklaus

Dissertations and Theses

Novel view synthesis is a classic problem in computer vision. It refers to the generation of previously unseen views of a scene from a set of sparse input images taken from different viewpoints. One example of novel view synthesis is the interpolation of views in between the two images of a stereo camera. Another classic problem in computer vision is video frame interpolation, which is important for video processing. It refers to the generation of video frames in between existing ones and is commonly used to increase the frame rate of a video or to match the frame rate to …


Before And After The Storm: Interactions Between Tree-Fall Canopy Gaps, Plant Phenology, And Frugivorous Lemurs In Masoala National Park, Madagascar, Monica Sue Mogilewsky Jan 2020

Before And After The Storm: Interactions Between Tree-Fall Canopy Gaps, Plant Phenology, And Frugivorous Lemurs In Masoala National Park, Madagascar, Monica Sue Mogilewsky

Dissertations and Theses

Madagascar is one of Earth's top biodiversity hotspots, with 80% of life on the island considered endemic. Among the endemic species are lemurs, a diverse group of non-human primates. Unfortunately, Madagascar's diversity, including lemurs, is threatened by habitat degradation and loss. Despite intense anthropogenic pressure over the past 50 years, scientists have not detected any lemur extinctions during this period. Some researchers have proposed that lemurs' adaptations to natural disturbances have provided these taxa resiliency against anthropogenic disturbances. Certainly, Madagascar experiences an extreme disturbance regime: the island experiences an average of over three cyclones a year. These cyclones create numerous, …


Modeling Spatiotemporal Patterns Of Pm2.5 At The Sub-Neighborhood Scale Using Low-Cost Sensor Networks, Philip Jeffrey Orlando Jan 2020

Modeling Spatiotemporal Patterns Of Pm2.5 At The Sub-Neighborhood Scale Using Low-Cost Sensor Networks, Philip Jeffrey Orlando

Dissertations and Theses

Epidemiological research has demonstrated an adverse relationship between fine particulate matter (PM2.5) and human health. While PM2.5 continues to pose a significant global health risk, there is still the need to further characterize exposures at the intra-urban scale. Land use regression is a statistical modeling technique which is used to predict air pollution concentrations at high resolution from a limited number of monitoring sites. However, the existing regulatory monitoring networks are typically not dense enough to apply these techniques. We explored the potential of using low-cost PM2.5 sensor networks to overcome the limitations of the existing …


Applications Of Triplet-Photosensitizers And Development Of Photochemical Methods, Luke V. Lutkus Jan 2020

Applications Of Triplet-Photosensitizers And Development Of Photochemical Methods, Luke V. Lutkus

Dissertations and Theses

Photochemistry focuses on various aspects of the interaction of light with molecules. This work entails new methodology for fundamental measurements of photochemistry along with novel applications of triplet-photosensitizers. Herein described are two separate methodologies developed for the determination of the quantum yield. A method for the singlet oxygen quantum yield was developed that utilizes the reaction between singlet oxygen and dimethyl sulfoxide (DMSO) to produce dimethyl sulfone. The rate of the reaction is measured by the pressure decrease that results from the consumption of oxygen from the headspace of a sealed system. It was found that the rate of pressure …


Geochemical Response To Thermal Energy Storage In The Columbia River Basalt Aquifer System Beneath The Portland Basin, Oregon, Ellen Elizabeth Svadlenak Jan 2020

Geochemical Response To Thermal Energy Storage In The Columbia River Basalt Aquifer System Beneath The Portland Basin, Oregon, Ellen Elizabeth Svadlenak

Dissertations and Theses

Deep direct use thermal energy storage (TES) is a low carbon emission method of geothermal energy storage and supply for large-scale residential, commercial, and manufacturing heating and cooling. The process entails repeated cycles of hot- or cold-water injection, storage, and extraction from slow groundwater flow zones within the deeper layers of an aquifer system. Though a promising technology, TES cycles may increase mineral dissolution and precipitation reactions, particularly at elevated temperatures. The ensuing mass transfer can form scale in heat exchange systems and alter aquifer porosity and permeability, processes that can reduce the operational efficiency of a TES system.

Within …


Glacial Meltwater Modeling To Simulate Lake Water Budget (1996-2013) In Taylor Valley, Antarctica, Julian Michael Cross Jan 2020

Glacial Meltwater Modeling To Simulate Lake Water Budget (1996-2013) In Taylor Valley, Antarctica, Julian Michael Cross

Dissertations and Theses

The McMurdo Dry Valleys (MDV), the largest ice-free region (4,500 km2) in Antarctica, are a polar desert with an average annual temperature of -18ºC. In Taylor Valley, one of the MDV, closed-basin, perennially ice-covered lakes occupy the valley floor. Their water balance is controlled by inflow from glacial meltwater runoff and loss due to sublimation, making them sensitive indicators of climate. In this study, a physically-based model of glacier meltwater and lake ice sublimation is adapted to explain modern (1996 to 2013) lake-level variations. Meltwater model results were improved by the inclusion of MODIS remotely-sensed albedo measurements (E …


Adapting To Extreme Heat: Social, Atmospheric, And Infrastructure Impacts Of Air Conditioning In Megacities - The Case Of New York City, Harold Gamarro Jan 2020

Adapting To Extreme Heat: Social, Atmospheric, And Infrastructure Impacts Of Air Conditioning In Megacities - The Case Of New York City, Harold Gamarro

Dissertations and Theses

Extreme heat events are becoming more frequent and intense in most large cities. Built-up surfaces also limit cooling mechanisms, leading to warmer conditions in cities, a phenomenon called the Urban Heat Island (UHI). This presents major challenges to reduce adverse health effects of hot weather, particularly in vulnerable populations like the elderly and low-income communities. Here we explore the overall impacts of increasing air conditioning (AC) system adoption in residences as an adaptive measure to reduce human health risks under heat waves, with New York City (NYC) as a case study. This study uses AC adoption data from the 2017 …


Ecosystem Health In Guánica Bay And La Parguera, Puerto Rico: Remote Sensing Of Ocean Color And Metal Analysis Of Coral Tissue And Surficial Sediments, Jahnelle Howe Jan 2020

Ecosystem Health In Guánica Bay And La Parguera, Puerto Rico: Remote Sensing Of Ocean Color And Metal Analysis Of Coral Tissue And Surficial Sediments, Jahnelle Howe

Dissertations and Theses

Guánica Bay is an estuary located in southwest Puerto Rico, with a coral reef ecosystem at its periphery. This ecosystem is affected by sediments, nutrients, and contaminants from the watershed through the Bay and into the offshore water. This project evaluates Guánica Bay and La Parguera coastal areas through remote sensing and chemical analysis to assess coastal ecosystem health. The concentration of metals in two coral species and their associated surface sediments was were analyzed by X-ray fluorescence (XRF) and Direct Mercury Analyzer (DMA- 80). Ocean color remote sensing was used to estimate nutrient inputs and phytoplankton biomass through chlorophyll- …


Mechanisms Of Value-Biased Prioritization In Fast Sensorimotor Decision Making, Kivilcim Afacan-Seref Jan 2020

Mechanisms Of Value-Biased Prioritization In Fast Sensorimotor Decision Making, Kivilcim Afacan-Seref

Dissertations and Theses

In dynamic environments, split-second sensorimotor decisions must be prioritized according to potential payoffs to maximize overall rewards. The impact of relative value on deliberative perceptual judgments has been examined extensively, but relatively little is known about value-biasing mechanisms in the common situation where physical evidence is strong but the time to act is severely limited. This research examines the behavioral and electrophysiological indices of how value biases split-second perceptual decisions and the possible mechanisms underlying the process. In prominent decision models, a noisy but statistically stationary representation of sensory evidence is integrated over time to an action-triggering bound, and value-biases …


Edge Device Speaker Verification, Thomas P. Duffy Jan 2020

Edge Device Speaker Verification, Thomas P. Duffy

Dissertations and Theses

The continued shrinking of processors and other physical hardware in concert with development of embeddable machine learning frameworks has enabled new use cases placing machine learning directly in the “wild”. The problem of speaker verification, for a long time, has been deployed to perform inference on systems with significant computations resources. More recently, these systems have been built for smaller, cheaper devices which can be placed in people's homes or other edge locations. Here, we aim to demonstrate that a reasonably accurate, generalizable, text-independent speaker verification system can be built, trained, and, ultimately, deployed onto a microcontroller with as a …


Ftir Analysis Of Bacteria Biomass-Mineral Interactions In Soils, Finola Fung-Khee Jan 2020

Ftir Analysis Of Bacteria Biomass-Mineral Interactions In Soils, Finola Fung-Khee

Dissertations and Theses

Soil organic carbon (SOC) accounts for 70% of the carbon on Earth. It is therefore a key player in global carbon cycling and climate change (Smith et al., 2008). Soil organic matter (SOM) is an important component of organic matter in soils (SOC), and results from biogeochemical process involving net primary producers, soil biomass and soil mineralogy (Horwath and Kuzyakov, 2018). In this study, the interplay between soil bacterial biomass and reactive clay minerals in soils was investigated. The purpose of the research was to shed light into the stabilization of SOC in a bacterial biomass-soil/clay matrix. Soils characterized as …


Macro - And Microstructure Evaluation And Field Applications Of Concrete With Recycled Glass Pozzolan, Marija Krstic Jan 2020

Macro - And Microstructure Evaluation And Field Applications Of Concrete With Recycled Glass Pozzolan, Marija Krstic

Dissertations and Theses

Concrete is the most used material in the world, second only to water. Conventional concrete is produced with Portland cement (PC). The production of cement is an energy intensive operation that has raised significant environmental concerns, since one ton of cement generates an equal ton of CO2. In the USA about 90 million tons of cement are used annually, with 3 million tons used in New York. Most contemporary concrete applications for buildings and infrastructure use high-performance concrete (HPC) mixtures which are produced by replacing a percentage of cement with supplementary cementitious materials (SCMs), consisting mainly of fly-ash …


Multimodal Data Integration For Real-Time Indoor Navigation Using A Smartphone, Yaohua Chang Jan 2020

Multimodal Data Integration For Real-Time Indoor Navigation Using A Smartphone, Yaohua Chang

Dissertations and Theses

We propose an integrated solution of indoor navigation using a smartphone, especially for assisting people with special needs, such as the blind and visually impaired (BVI) individuals. The system consists of three components: hybrid modeling, real-time navigation, and client-server architecture. In the hybrid modeling component, the hybrid model of a building is created region by region and is organized in a graph structure with nodes as destinations and landmarks, and edges as traversal paths between nodes. A Wi-Fi/cellular-data connectivity map, a beacon signal strength map, a 3D visual model (with destinations and landmarks annotated) are collected while a modeler walks …


Sugar-Derived Oleogels In Cosmetics And Food Applications: A Case Study Of Trehalose- And Mannitol-Based Gelators, Polina Tsupko Jan 2020

Sugar-Derived Oleogels In Cosmetics And Food Applications: A Case Study Of Trehalose- And Mannitol-Based Gelators, Polina Tsupko

Dissertations and Theses

Gels represent an indispensable part of our everyday lives with direct applications in food, medicine, cosmetics and other industries. Amphiphilic molecules have been shown to act as low molecular weight gelators (LMWGs) and are becoming the main focus of several research groups. Their ability to self-assemble into various morphologies from micelles to bilayer sheets, and remain stable due to noncovalent forces responsible for the formation of the 3D network—Self-Assembled Fibrillar Network (SAFiNs)—is in the core of their ability to produce molecular gels. Those amphiphilic molecules capable of adsorbing at the interface and behaving as surface active agents are known as …