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Full-Text Articles in Physical Sciences and Mathematics

The On-Line Width Of Various Classes Of Posets., Israel R. Curbelo Aug 2022

The On-Line Width Of Various Classes Of Posets., Israel R. Curbelo

Electronic Theses and Dissertations

An on-line chain partitioning algorithm receives a poset, one element at a time, and irrevocably assigns the element to one of the chains. Over 30 years ago, Szemer\'edi proved that any on-line algorithm could be forced to use $\binom{w+1}{2}$ chains to partition a poset of width $w$. The maximum number of chains that can be forced on any on-line algorithm remains unknown. In the survey paper by Bosek et al., variants of the problem were studied where the class is restricted to posets of bounded dimension or where the poset is presented via a realizer of size $d$. We prove …


Classifying The 2022 Status Of Tsuga Canadensis (Eastern Hemlock) Along The Kentucky Portion Of The Pine Mountain Wildlands Corridor., Grace M. Embree Aug 2022

Classifying The 2022 Status Of Tsuga Canadensis (Eastern Hemlock) Along The Kentucky Portion Of The Pine Mountain Wildlands Corridor., Grace M. Embree

Electronic Theses and Dissertations

The invasion of the Hemlock Woolly Adelgid (HWA) (Adelges tsugae) has posed a continual threat in the United States to the Eastern Hemlock (Tsuga canadensis) trees since the 1950s. HWA feed on eastern hemlock needles, reducing the amount of healthy photosynthesizing vegetative area. The use of satellite imagery has been instrumental in identifying areas of eastern hemlock presence. Satellite platforms like Landsat and AVIRIS are commonly used for identification, classification, and mapping of eastern hemlock. Sentinel-2 imagery was released in 2015 for free access. It has a finer spatial grain of with the majority of the …


A Computational Model Of The Line-1 Retrotransposon Life Cycle And Visualization Of Metabolic Networks In 3-Dimensions., Michael D. Martin Aug 2022

A Computational Model Of The Line-1 Retrotransposon Life Cycle And Visualization Of Metabolic Networks In 3-Dimensions., Michael D. Martin

Electronic Theses and Dissertations

Computational modeling of metabolic reactions and cellular systems is evolving as a tool for quantitative prediction of metabolic parameters and reaction pathway analysis. In this work, the basics of computational cell biology are presented as well as a summary of physical processes within the cell, and the algorithmic methods used to find time dependent solutions. Protein-protein and enzyme-substrate interactions are mathematically represented via mass action kinetics to construct sets of linear differential equations that describe reaction rates and formation of protein complexes. Using mass action methods, examples of reaction networks and their solutions are presented within the Virtual Cell simulation …


Role Of Deep Learning Techniques In Non-Invasive Diagnosis Of Human Diseases., Hisham Abouelseoud Elsayem Abdeltawab Aug 2022

Role Of Deep Learning Techniques In Non-Invasive Diagnosis Of Human Diseases., Hisham Abouelseoud Elsayem Abdeltawab

Electronic Theses and Dissertations

Machine learning, a sub-discipline in the domain of artificial intelligence, concentrates on algorithms able to learn and/or adapt their structure (e.g., parameters) based on a set of observed data. The adaptation is performed by optimizing over a cost function. Machine learning obtained a great attention in the biomedical community because it offers a promise for improving sensitivity and/or specificity of detection and diagnosis of diseases. It also can increase objectivity of the decision making, decrease the time and effort on health care professionals during the process of disease detection and diagnosis. The potential impact of machine learning is greater than …


Dimension And Ramsey Results In Partially Ordered Sets., Sida Wan Aug 2022

Dimension And Ramsey Results In Partially Ordered Sets., Sida Wan

Electronic Theses and Dissertations

In this dissertation, there are two major parts. One is the dimension results on different classes of partially ordered sets. We developed new tools and theorems to solve the bounds on interval orders using different number of lengths. We also discussed the dimension of interval orders that have a representation with interval lengths in a certain range. We further discussed the interval dimension and semi dimension for posets. In the second part, we discussed several related results on the Ramsey theory of grids, the results involve the application of Product Ramsey Theorem and Partition Ramsey Theorem


Statistical Methods For Personalized Treatment Selection And Survival Data Analysis Based On Observational Data With High-Dimensional Covariates., Don Ramesh Dinendra Sudaraka Tholkage Aug 2022

Statistical Methods For Personalized Treatment Selection And Survival Data Analysis Based On Observational Data With High-Dimensional Covariates., Don Ramesh Dinendra Sudaraka Tholkage

Electronic Theses and Dissertations

Due to the wide availability of functional data from multiple disciplines, the studies of functional data analysis have become popular in the recent literature. However, the related development in censored survival data has been relatively sparse. In Chapter 2, we consider the problem of analyzing time-to-event data in the presence of functional predictors. We develop a conditional generalized Kaplan Meier (KM) estimator that incorporates functional predictors using kernel weights and rigorously establishes its asymptotic properties. In addition, we propose to select the optimal bandwidth based on a time-dependent Brier score. We then carry out extensive numerical studies to examine the …


Search For A Dark Leptophilic Scalar Produced In Association With Taupair In Electron-Positron Annihilation At Center-Of-Mass Energies Near 10.58 Gev., Diptaparna Biswas Aug 2022

Search For A Dark Leptophilic Scalar Produced In Association With Taupair In Electron-Positron Annihilation At Center-Of-Mass Energies Near 10.58 Gev., Diptaparna Biswas

Electronic Theses and Dissertations

Dark matter is believed to be a form of matter which seemingly accounts for approximately 85% of the matter in the universe and about 27% of its total mass–energy density. It doesn't participate in electromagnetic interaction, i.e. doesn't interact with light. Consequently, we cannot see it using optical or radio telescope and hence the name dark matter. However, it participates in gravitational interaction, and we hypothesize its existence based on a variety of astrophysical observations, including gravitational effects, that cannot be explained by the accepted theories of gravity unless we account for more matter than can be perceived through electromagnetic …


Effects Of Monovalent And Divalent Ions In Factor Xiii Activation And Crosslinking., Richard Laporca Lumata Aug 2022

Effects Of Monovalent And Divalent Ions In Factor Xiii Activation And Crosslinking., Richard Laporca Lumata

Electronic Theses and Dissertations

Factor XIII (FXIII) is an emerging target for treating blood clotting and cardiovascular related diseases. FXIII can be activated non-proteolytically by the presence of elevated Ca2+ levels (2-100 mM) or proteolytically by thrombin-cleavage of the Activation Peptide along with low mM Ca2+. The studies herein utilized fluorescence to examine how monovalent and divalent ions influence the transglutaminase activity and conformation of FXIII. Monodansylcadaverine assays revealed that increasing ionic radius (Cs+ > K+ > Na+ > Li+) and increasing ionic strength (XCl- levels and SO42- > Cl-) elevated FXIII-A transglutaminase activity. Intrinsic …


Cross-Validation For Autoregressive Models., Christina Han Aug 2022

Cross-Validation For Autoregressive Models., Christina Han

Electronic Theses and Dissertations

There are no set rules for choosing the lag order for autoregressive (AR) time series models. Currently, the most common methods employ AIC or BIC. However, AIC has been proven to be inconsistent and BIC is inefficient. Racine proposed an estimator based on Shao's work which he hypothesized would also be consistent, but left the proof as an open problem. We will show his claim does not follow immediately from Shao. However, Shao offered another consistent method for cross validation of linear models called APCV, and we will show that AR models satisfy Shao's conditions. Thus, APCV is a consistent …


Community Structure Analysis Of Turtles With Application To The Early Pliocene Gray Fossil Site, Julian Conley Aug 2022

Community Structure Analysis Of Turtles With Application To The Early Pliocene Gray Fossil Site, Julian Conley

Electronic Theses and Dissertations

Turtles are important components of ecosystems around the world, with diverse ecological niches and adaptations. However, there are few detailed studies of how turtle community structure reflects local environments. This project applied techniques of community structure analysis to sites across the United States to infer past ecosystem and environmental conditions of the early Pliocene Gray Fossil Site (GFS) in northeastern Tennessee based on the ancient turtle community. Results indicate extant turtle community structure closely reflects environmental conditions, and that ancient turtle communities can be used to infer climate and habitat conditions of past ecosystems. Application to the GFS turtle community …


A New Sir Model With Mobility., Ciana Applegate Aug 2022

A New Sir Model With Mobility., Ciana Applegate

Electronic Theses and Dissertations

In this paper, a mobility-based SIR model is built to understand the spread of the pandemic. A traditional SIR model used in epidemiology describes the transition of particles among states, such as susceptible, infected, and recovered states. However, the traditional model has no movement of particles. There are many variations of SIR models when it comes to the factor of mobility, the majority of studies use mobility intensity or population density as a measure of mobility. In this paper, a new dynamical SIR model, including the spatial motion of three-type particles, is constructed and the long-time behavior of the first …


Sustainability As Justice Engaging With North American Alternative Seafood Networks Through Participatory Action Research, Paloma Henriques Jul 2022

Sustainability As Justice Engaging With North American Alternative Seafood Networks Through Participatory Action Research, Paloma Henriques

Electronic Theses and Dissertations

Transformations in the ways we relate to the ocean are long overdue given the myriad of anthropogenic problems that exist – from overfishing to plastic pollution and acidification to ‘slavery-at-sea ’ and loss of access and fishing rights. Yet alongside the hegemonic modes of ocean exploitation exist diverse alternative economies, including those associated with alternative seafood networks, that aim to create different and more-than-economic relationships with marine systems. To situate my research within the broader literature, I interpret the widely used Brundtland Report definition of sustainability, “meet[ing] the needs of the present without compromising the ability of future generations to …


Loggerhead Shrike Detectability And Occurrence In Coastal South Carolina Urban Areas, Michelle Krauser May 2022

Loggerhead Shrike Detectability And Occurrence In Coastal South Carolina Urban Areas, Michelle Krauser

Electronic Theses and Dissertations

Grassland birds, such as the loggerhead shrike (Lanius ludovicianus), are threatened by extensive land-use change, including urbanization. Loggerhead shrikes have been declining since the early 1900s and are rare or extirpated in portions of their former range. Obtaining reliable population estimates of loggerhead shrikes is important to identify demographic trends and ensure conservation decisions are based on an accurate assessment of their current status. Imperfect detection, or the inability to detect every shrike during a survey, can result in biased population estimates. Estimating detection probability is labor-intensive and requires assumptions that are difficult to satisfy in most field studies. Understanding …


Steps Toward The Total Synthesis Of The Chrysosporazine Family, Katie Kaczynski May 2022

Steps Toward The Total Synthesis Of The Chrysosporazine Family, Katie Kaczynski

Electronic Theses and Dissertations

Cancer is one of the leading causes of death worldwide, with 19.3 million new cancer cases and 10 million deaths in 2020 alone. In the United States, cancer was the second leading cause of death after heart disease. One of the reasons that cancer is so frequently terminal is that cancerous cells frequently develop multidrug resistance (MDR) to frontline chemotherapeutical treatments, resulting in cancers cannot be treated and are inevitably fatal. This makes the discovery of ways to combat MDR so important in the treatment of cancer. The chrysosporazines are a family of recently discovered (2019) natural products that have …


Rooted In The Earth: An Igbo Sacramental Nature Of The Universe, A Model For Igbo Christian Ecological Ethics, Kenneth Oguzie May 2022

Rooted In The Earth: An Igbo Sacramental Nature Of The Universe, A Model For Igbo Christian Ecological Ethics, Kenneth Oguzie

Electronic Theses and Dissertations

The contemporary Igbo society faces a lot of challenges. These include political, religious, and moral crises. These crises affect the environment in many ways. They threaten the peace and harmony of the Igbo society. As a result, it touches on faith. The Igbo society holds a holistic view of life. Whatever affects one aspect of life affects the other areas. Ecologically, various factors are responsible for the crises. These include changes in lifestyle from the traditional way of living to modern style of life with its penchant on consumerism. Also, colonialism and its lingering residues, civil unrests, politics, population growth, …


Biomaterials: From Scaffold Design To Implant Optimization, Jennifer Marie Armen May 2022

Biomaterials: From Scaffold Design To Implant Optimization, Jennifer Marie Armen

Electronic Theses and Dissertations

This work encompasses three individual projects concerning biomaterials and their modifications. Chemically-Induced Cross-Linking of Peptidic Fibrils for Scaffolding Polymeric Particles and Macrophages EAK16-II (EAK) is a self-assembling peptide (SAP) that forms β-sheets and βfibrils through ionic-complementary interactions at physiological ionic strengths. The soft materials can be injected in vivo, creating depots of drugs and cells for rendering pharmacological and biological actions. The scope of the applications of EAK is sought to extend to tissues through which the flow of extracellular fluid tends to be limited. In such anatomical locales the rate and extent of the fibrilization are limited insofar as …


Turbulent Transport Of Dissolved Oxygen In Natural Channels, Alanna Bachtlin May 2022

Turbulent Transport Of Dissolved Oxygen In Natural Channels, Alanna Bachtlin

Electronic Theses and Dissertations

The transport and mixing of dissolved oxygen (DO) is important to replenish the oxygen depleted by natural processes; gas transfer in general has implications for ecosystem metabolism and greenhouse gas transfer. Currently, reaeration coefficients can be found through gas tracer methods, which estimates one-way gas transfer. For this project, a net oxygen consumption rate, , was developed using the similarity equations, which provides a value from DO and velocity profiles specific to a stream site. Additionally, three models to calculate friction velocity, which is required for oxygen consumption rate, were compared. Reynolds stresses, mathematically developed in the Reynolds-Averaged Navier-Stokes Equations, …


The Contribution Of Ethical Governance Of Artificial Intelligence & Machine Learning In Healthcare, Tina Nguyen May 2022

The Contribution Of Ethical Governance Of Artificial Intelligence & Machine Learning In Healthcare, Tina Nguyen

Electronic Theses and Dissertations

With the Internet Age and technology progressively advancing every year, the usage of Artificial Intelligence (AI) along with Machine Learning (ML) algorithms has only increased since its introduction to society. Specifically, in the healthcare field, AI/ML has proven to its end-users how beneficial its assistance has been. However, despite its effectiveness and efficiencies, AI/ML has also been under scrutiny due to its unethical outcomes. As a result of this, two polarizing views are typically debated when discussing AI/ML. One side believes that AI/ML usage should continue regardless of its unsureness, while the other side argues that this technology is too …


C-H On The Oxo Ferryl Wheel: Comparison Of Pyridine And Imidazole-Substituted Ligands For C-H Activation And Functionalization, Elizabeth Milem May 2022

C-H On The Oxo Ferryl Wheel: Comparison Of Pyridine And Imidazole-Substituted Ligands For C-H Activation And Functionalization, Elizabeth Milem

Electronic Theses and Dissertations

The selective and efficient transformation of hydrocarbon feedstocks is of high value for industry and research. While Shilov-type organometallic methods have facilitated this goal, systems designed after nature’s use of cheap and abundant iron-based enzymes are desired for wider-scale applications. This work establishes hydrocarbon oxidation efficiency of synthetic pyridine-based ligands (BPMEN, BPMPN) compared to commercially available TPA with in situ generated catalysts. Literature studies of traditionally synthesized BPMEN systems and initial in situ studies offered evidence for enhanced reactivity (TON) as compared to TPA. Expansion to a propyl backbone to produce BPMPN tested the increased chelate ring size’s impact on …


An Application Of Differential Mathematical Modeling Techniques To Study The Ongoing Rabies Epizootic In China, Christopher Turner May 2022

An Application Of Differential Mathematical Modeling Techniques To Study The Ongoing Rabies Epizootic In China, Christopher Turner

Electronic Theses and Dissertations

Rabies remains a global public health issue with a wide variety of neurological symptoms such as confusion, slight paralysis, hypersalivation, and hydrophobia. Rabies is usually fatal once symptoms appear. Many species are reservoirs for rabies, such as foxes, racoons, and wild dogs, which in turn can transmit the disease to humans, leading to complex transmission chains. There is a long latent period of rabies, between 1 to 3 months after infection, which further complicates control efforts. Mathematical modeling is a valuable tool in the study of infectious disease outbreaks and there have been many models applied to rabies outbreaks. However, …


Giving Form To Flow: Modeling The Paleohydrological Context For Human Settlement And Water Use In The North-Central Coast Of Peru, Elizabeth Leclerc May 2022

Giving Form To Flow: Modeling The Paleohydrological Context For Human Settlement And Water Use In The North-Central Coast Of Peru, Elizabeth Leclerc

Electronic Theses and Dissertations

Within coastal Andean archaeology there is a growing emphasis on the roles of hydrology and hydrological knowledge in Andean strategies for water management, settlement, and land use. Hydrological methods can not only help reconstruct past water environments but also illuminate the influence of changing climates and conditions in the Andean highlands on coastal water flows. Through a case study of the Supe River basin in north-central coastal Peru, focusing on the period from 5000 to 3000 calibrated radiocarbon years before present (cal. BP), I review several hydrological methods useful for archaeological study. I then combine these to develop a paleohydrological …


Sustainability Conversations For Impact: Transdisciplinarity On Four Scales, Katrina Brewster Pugh May 2022

Sustainability Conversations For Impact: Transdisciplinarity On Four Scales, Katrina Brewster Pugh

Electronic Theses and Dissertations

Sustainability is a dynamic, multi-scale endeavor. Coherence can be lost between scales – from project teams, to organizations, to networks, and, most importantly, down to conversations. Sustainability researchers have embraced transdisciplinarity, as it is grounded in science, shared language, broad participation, and respect for difference. Yet, transdisciplinarity at these four scales is not well-defined. In this dissertation I extend transdisciplinarity out from the project to networks and organizations, and down into conversation, adding novel lenses and quantitative approaches. In Chapter 2, I propose transdisciplinarity incorporate academic disciplines which help cross scales: Organizational Learning, Knowledge Management, Applied Cooperation, and Data Science. …


Evaluating Physical And Cultural Methods To Improve Weed Management In Organic Vegetables, Rebecca J. Champagne May 2022

Evaluating Physical And Cultural Methods To Improve Weed Management In Organic Vegetables, Rebecca J. Champagne

Electronic Theses and Dissertations

Effectively managing weeds in organic vegetable production continues to be challenging and costly. Cultivation, often referred to as physical weed control (PWC), is foundational for organic farmers; however, efficacy tends to be low and highly variable. Additionally, some crops are slow to germinate, and thus have poor competitive ability against weeds and high mortality from cultivation. This can result in high costs for hand-weeding labor, abundant seed rain into the soil, and a recurring, often increasing, weed problem. These challenges may be addressed by “stacking” tools to increase weed control efficacy, integrating targeted seedbank management strategies to reduce the germinable …


Fabrication Of Particulates For Detecting Trace Level Analytes In Water Using Optical Spectroscopy And For Developing Thermoelectric Materials, Mohammed Nayeem Ibnul May 2022

Fabrication Of Particulates For Detecting Trace Level Analytes In Water Using Optical Spectroscopy And For Developing Thermoelectric Materials, Mohammed Nayeem Ibnul

Electronic Theses and Dissertations

The underlying concepts developed in this thesis involve particulate fabrication of known size using a bottom-up synthesis or a top-down milling process. This bottom-up approach was used for detection of analytes in water. Conventional UV-Vis spectroscopic based detection methods require target analytes to be soluble or have enough vapor pressure for analysis in the gas phase. We achieved an order in magnitude improvement in the detection limit over the standard molybdenum blue method for phosphate and arsenate by conversion of target analytes present in solution to a solid for quantification by UV-Vis and IR spectroscopy. Furthermore, by recording a visible …


Enhanced Condition Assessment For Maine Lakes, Jeremy Deeds May 2022

Enhanced Condition Assessment For Maine Lakes, Jeremy Deeds

Electronic Theses and Dissertations

The Influence of anthropogenic activities on lake water quality is well documented, but how those influences interact with the effects of natural features, such as watershed geology or lake morphometry, has been less explored. Further, some aspects of lake condition are influenced by factors that are not lake or watershed specific, but occur across large regions, such as weather patterns. All these factors may be interrelated in some instances, which can complicate lake condition assessments which have the purpose of determining how lakes are being affected by human activities. This dissertation investigates how lake assessments can integrate the interactions among …


Building Monitoring And Response Capacity For Ocean And Coastal Acidification In The Northeast United States, Parker Gassett May 2022

Building Monitoring And Response Capacity For Ocean And Coastal Acidification In The Northeast United States, Parker Gassett

Electronic Theses and Dissertations

Ocean and coastal acidification (OCA) present a unique set of sustainability challenges at the human-ecological interface, and the waters and communities of the Gulf of Maine are among the most vulnerable to this environmental threat. Successful adaptation and mitigation options to address myriad impacts of OCA– including actions by marine resource and water quality managers, the scientific community, and the aquaculture and fishing industry – depend strongly on the availability of monitoring that can inform decision-making and on developing and implementing best practices for resilience at the community level. Collaboration between technical experts, facilitators, and a locally engaged citizenry can …


Structure From Motion Methodology Captures Seasonal Influences On Coastal Bluff Erosion And Landslide Hazards In Casco Bay, Me, Nicholas Whiteman May 2022

Structure From Motion Methodology Captures Seasonal Influences On Coastal Bluff Erosion And Landslide Hazards In Casco Bay, Me, Nicholas Whiteman

Electronic Theses and Dissertations

Shoreline erosion in response to rising sea level is a global problem. Recognizing the need for observational data on coastal bluff recession in Casco Bay, Maine, we employed Structure from Motion (SfM) photogrammetric methods in a dynamic intertidal environment. Evaluating the method as a means to measure and monitor dynamic geomorphological changes occurring at a coastal bluff shows that a spatial resolution of centimeters over an area of 10’s to 100’s of meters can be attained at relatively low cost. The efficient methodology allows for frequent surveys at an operational scale, leading to greater temporal resolution and quantification of bluff …


Development And Evaluation Of Modeling Approaches For Extrusion-Based Additive Manufacturing Of Thermoplastics, Christopher C. Bock May 2022

Development And Evaluation Of Modeling Approaches For Extrusion-Based Additive Manufacturing Of Thermoplastics, Christopher C. Bock

Electronic Theses and Dissertations

This work focuses on evaluating different modeling approaches and model parameters for thermoplastic AM, with the goal of informing more efficient and effective modeling approaches. First, different modeling approaches were tested and compared to experiments. From this it was found that all three of the modeling approaches provide comparable results and provide similar results to experiments. Then one of the modeling approaches was tested on large scale geometries, and it was found that the model results matched experiments closely. Then the effect of different material properties was evaluated, this was done by performing a fractional factorial design of experiments where …


Age, Growth, Foraging, And Trophic Ecology Of Bigeye (Thunnus Obesus) And Yellowfin (Thunnus Albacares) Tuna In Continental Shelf And Slope Regions Of The Northeast U.S., Riley S. Austin May 2022

Age, Growth, Foraging, And Trophic Ecology Of Bigeye (Thunnus Obesus) And Yellowfin (Thunnus Albacares) Tuna In Continental Shelf And Slope Regions Of The Northeast U.S., Riley S. Austin

Electronic Theses and Dissertations

Traditional stock assessments require, in part, accurate knowledge of growth relationships to estimate a variety of aspects involved in population conservation management of exploited species. In addition, the local distribution and condition of top pelagic predators is driven by detection of abundant forage aggregations and along with traditional stock assessments, should be considered for effective management of marine populations. Empirical analyses of these data are severely lacking for bigeye (Thunnus obesus) and yellowfin (Thunnus albacares) tuna in the Atlantic Ocean, especially for the former. Given historical studies’ observations of these two top predators use as biological samplers due to their …


Overlapping Scales Of Place Based Indigenous Knowledge And Hydroclimate In Australia, Rachel L. Coleman May 2022

Overlapping Scales Of Place Based Indigenous Knowledge And Hydroclimate In Australia, Rachel L. Coleman

Electronic Theses and Dissertations

Indigenous Peoples have been monitoring and adapting to uncertainty and change in their local regions for millennia, resulting in a holistic view of the interlinkages within the occupied complex socio-environmental systems. This research consists of investigating the overlapping scales of knowledge within Indigenous Australian seasonal calendars and colonial methods of hydroclimate assessment for improving adaptability to climate change impacts.

The analyses began with a sample of 25 Indigenous seasonal calendars providing a glimpse into interlinkages among biota, environment, and meteorology of the localised regions. Across the calendars, five themes of information and multiple categories within these themes became apparent and …