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Processes In The Percolation Zone In Southwest Greenland: Challenges In Modeling Surface Energy Balance And Melt, And The Role Of Topography In The Formation Of Ice Slabs, Federico Covi

Geosciences

Increased surface melt in the percolation zone of Greenland causes significant changes in the firn structure, directly affecting the surface mass balance of the ice sheet and the amount and timing of meltwater runoff. Thick impermeable layers, referred to as ice slabs, are preventing melt water percolation and refreezing in the firn favoring lateral movement of water and direct runoff to the oceans. The objective of this dissertation is to enhance the understanding of these processes by modeling the surface energy balance and resulting melt, and investigating the spatial and temporal changes in firn surface properties and associated water movement …

Acoustic And Seismic Signature Of Sustained Volcanic Eruptions, Julia E. Gestrich

Geosciences

Volcanic eruptions of any size can pose a significant risk to the life and livelihood of humans, as well as to infrastructure and the economy. Understanding the dynamics of an eruption is crucial to providing timely and accurate assessments of the eruption and associated hazard. Ideally the monitoring of volcanic unrest and eruption dynamics is done remotely to minimize exposure to volcanologists and maximize the spatial monitoring coverage of instruments. Another important factor is to have real-time data to facilitate rapid analysis and interpretation. Seismic and acoustic (infrasound) waves have proven useful in terms of remote real-time volcano monitoring. However, …

A Wiggle Around A Giant: Exploring The Hot Electrons Within The Io Torus, Drew Coffin

Physics

Jupiter exhibits a fundamental rotational periodicity known as System IV that has no widely-accepted explanation, yet is easily observed in ultraviolet emission from the plasma torus generated by the innermost Galilean moon Io. This periodicity around Jupiter maps to a persistent, radially independent subcorotation within the Io plasma torus. In this thesis, we explore the origin and consequences of this periodicity. Using an equatorial chemistry and diffusive transport model, we demonstrate that a prescribed hot electron population produces a coherent wave of heightened energy flow that induces a consistent subcorotation. This additional hot electron population is consistent with the energization …

Controllability Of Non-Self-Adjoint Systems Of Partial Differential Equations, Jeff Park

Mathematics and Statistics

In this dissertation, we first consider the problem of exact controllability of a system of N one-dimensional coupled wave equations when the control is exerted on a part of the boundary by means of one control. We provide a Kalman condition (necessary and sufficient) and give a description of the attainable set. The second problem we consider is the inverse problem for the vector Schrödinger equation on the interval with a non-self-adjoint matrix potential. In doing so, we prove controllability of the system and develop a method to recover spectral data from the system. Then, we solve the inverse problem …

Control And Inverse Problems For The Wave Equation On Metric Graphs, Yuanyuan Zhao

Mathematics and Statistics

This thesis focuses on control and inverse problems for the wave equation on finite metric graphs. The first part deals with the control problem for the wave equation on tree graphs. We propose new constructive algorithms for solving initial boundary value problems on general graphs and boundary control problems on tree graphs. We demonstrate that the wave equation on a tree is exactly controllable if and only if controls are applied at all or all but one of the boundary vertices. We find the minimal controllability time and prove that our result is optimal in the general case. The second …

Computing Prime Factorizations With Neural Networks, Dakota Dragomir

Mathematics and Statistics

When dealing with sufficiently large integers, even the most cutting-edge existing algorithms for computing prime factorizations are impractically slow. In this paper, we explore the possibility of using neural networks to approximate prime factorizations in the hopes of providing an alternative factorization method which trades accuracy for speed. Due to the intrinsic difficulty associated with this task, the focus of this paper is largely concentrated on the obstacles encountered in the training of the neural net, rather than on the viability of the method itself.

Implications Of Spatial Population Dynamics For Abundance Estimation And Catch Apportionment Of Alaska Sablefish (Anoplopoma Fimbria), Kari Hammarsten Fenske

Fisheries

Spatial dynamics in fish populations are challenging to identify and incorporate into population dynamics models due to the large amount of data required and the uncertainty associated with spatial processes. However, ignoring spatial dynamics can result in biased population estimates and negatively affect population sustainability or the ability to meet fishery management goals. My research explored implications of spatial dynamics for the assessment and management of Alaska sablefish (Anoplopoma fimbria). Sablefish are highly mobile, targeted in commercial and recreational fisheries, and documented to have spatial variation in population dynamics such as abundance and biomass. However, gaps remain in understanding the …

Freshwater Pressures On Pacific Salmon In The Coastal Watersheds Of Alaska, Christopher J. Sergeant

Fisheries

This dissertation explores the implications of a warmer and wetter climate on the freshwater life stages of Pacific salmon (Oncorhynchus spp.) in the focal region of southern coastal Alaska. Recent trends and long-term climate change predictions support the notion that arctic and subarctic watersheds will be subject to warming air temperatures, increased rainfall in the autumn and winter, diminishing snowpack, and continued glacial recession. Such atmospheric and terrestrial changes will shift patterns of streamflow, water temperature, and habitat diversity that comprise the basic building blocks of freshwater ecosystems that support Pacific salmon. Alaska's Pacific salmon populations sustain a multi-billion-dollar economy …

Investigating The Effectiveness Of Prehospital Recognition And Administration Of Intravenous Antibiotics In Septic Patients, Laura Keane, Ian Peterson

Physician Assistant Capstones, 2020-current

Objective: To compare the 30-day mortality rate of suspected sepsis patients who received prehospital (Emergency Medical Services- EMS) antibiotic administration in an ambulance as compared to antibiotic administration in the hospital. Design: Systematic literature review. Methods: Research was conducted in PubMed and Google Scholar with the search terms: sepsis, antibiotics, prehospital, EMS, ambulance. The 3 articles selected were chosen after removing articles not from a randomized control trial, no antibiotic administration, and not a free article. Results: From our meta-analysis of the three studies, we concluded that providing antibiotics before arriving at the hospital for patients with suspected septic infections. …

Bringing Gifts To The Manger, Ann Zlotnik

Marian Library Blog Archive

For the fourth week of Advent, we present Nativity sets that are full of gifts and full of love for the infant Jesus.

Sled Dogs As Gifts. An Ethnography Of Dog Exchanges Among Kennels In Alaska., Allison K. Cruz

Anthropology

This thesis investigates the social relationships that develop through the circulation of sled dogs among Alaskan kennels. It is based on multi-sited ethnographic fieldwork at racing events, in sled dog kennels, as well as semi-structured interviews around Fairbanks. The research is informed by anthropological literature on kinship, personhood, and gift-giving economies. It examines how sled dogs are acquired and exchanged in Alaska and offers a novel perspective on the value of dog bloodlines and the relationships that unite breeders, mushers and sled dogs. The main argument is that Alaskan sled dogs are exchanged as gifts (rather than commodities) with the …

Species Distribution Modeling Of Northern Sea Otters (Enhydra Lutris Kenyoni) In A Data-Limited Ecosystem, Elizabeth L. Hasan

Marine Biology

Species distribution models are used to map and predict geographic distributions of animals based on environmental covariates. However, species distribution models often require high resolution habitat data and time-series data on animal locations. In data-limited regions with little animal survey data or habitat information, modeling is more challenging and often ignores important environmental attributes. For sea otters (Enhydra lutris), a federally protected keystone species with variable population trends across their range, predictive modeling of distributions has been successfully conducted in areas with an abundance of sea otter and habitat data. Here, we used open-access data across a single time step …

Acute Toxicity Of Copper To Three Species Of Pacific Salmon In Water With Low Hardness And Low Dissolved Organic Carbon, Drew E. Porter

Marine Biology

Despite a history of investigation, the toxicity of copper (Cu) to fishes remains difficult to predict due to the complex influential effects of water chemistry. Water hardness and dissolved organic carbon (DOC) concentrations can vary significantly within a watershed and also attenuate the toxicity of Cu to fishes. To account for location-specific water chemistry and predict Cu toxicity to aquatic organisms the United States Environmental Protection Agency (USEPA) endorses use of the biotic ligand model (BLM). Though the BLM has proven useful in many instances, it has performed inaccurately for waters low in hardness and DOC; this has raised questions …

Compound-Specific Stable Isotopes Of Amino Acids Reveal The Influence Of Trophic Level And Primary Production Sources On Mercury Concentrations In Fishes From The Aleutian Islands, Alaska, N/A N/A

Marine Biology

Total mercury (THg) concentrations exceed thresholds of concern in some Steller sea lion (Eumetopias jubatus; SSL) tissues from certain portions of the Aleutian Islands, Alaska. Here, compound-specific stable isotope analyses (CSIA) of carbon in essential amino acids ([delta]¹³CEAA values) and nitrogen in AAs ([delta]¹⁵NAA values) in fish muscle tissue was applied to quantify the proportional contributions of primary production sources and trophic positions of eight prey species (n = 474 total) that are part of SSL diets. Previous THg analyses of fish muscle, coupled with additional monomethylmercury (MMHg) analyses of a subset of samples, substantiated previous findings that fishes from …

Drivers Of Functional Ecology Of The Alaskan Arctic Epibenthos, Lauren Sutton

Marine Biology

This dissertation explored multiple facets of functional diversity for epibenthic invertebrate communities of Alaskan Arctic shelves. Functional diversity is the range of organismal traits within a community that determines ecosystem functioning. As a complement to taxonomic diversity, functional diversity reflects what species "do" as opposed to "who" they are, providing information on community-level ecosystem resilience and vulnerability. The Alaskan Arctic marine system is presently changing at an unprecedented rate, which impacts the biomass-rich benthos that is of great importance to upper trophic level fishes, birds, and marine mammals as a food source. In my first chapter, I tested the Biodiversity-Ecosystem-Functioning …

Exploring The North American Arctic Benthos: Community Structure And Oil Degradation Potential Of Sediment Bacteria And Archaea, Alexis M. Walker

Marine Biology

The Chukchi and Beaufort seas benthic habitats are home to a multitude of ecologically and commercially important organisms that are subject to ongoing environmental changes, including the impacts of climate change and increased exposure to contaminants. Benthic bacteria and archaea can be considered biogeochemical engineers. They play a major role in organic matter (OM) degradation and nutrient cycling and their community structure can reflect changes in environmental conditions such as OM composition and quantity, nutrient availability, redox conditions, and natural/anthropogenic contaminants (e.g. petroleum hydrocarbons). Yet, sediment microbial communities have rarely been examined in these marginal seas of North American Arctic. …

Seaweeds Across Ecosystem Boundaries: From Habitat Formation To Harvest Implications, Brian P. Ulaski

Marine Biology

This dissertation broadly investigates the response of wild stock seaweeds to harvesting, and their role as biogenic habitat formers when cast ashore. Seaweeds are important primary producers and foundation species that maintain their functional roles across coastal ecosystem boundaries. Climate-driven loss of seaweed biomass, including that of kelp forests, is exacerbated by other human-related activities that directly impact their persistence, such as overharvesting. Attached rockweeds and kelps are commonly harvested for food, while diverse assemblages of beach-cast seaweed wrack are collected for fertilizer. The importance of wrack habitat in Alaska has not been extensively explored, especially in regions where there …

Distribution Network Planning And Operation With Autonomous Agents, Abdulraheem Hassan Alobaidi

Electrical Engineering Theses and Dissertations

With the restructured power system, different system operators and private investors are responsible for operating and maintaining the electricity networks. Moreover, with incentives for a clean environment and reducing the reliance on fossil fuel generation, future distribution networks adopt a considerable penetration of renewable energy sources. However, the uncertainty of renewable energy sources poses operational challenges in distribution networks. This thesis addresses the planning and operation of the distribution network with autonomous agents under uncertainty. First, a decentralized energy management system for unbalanced networked microgrids is developed. The energy management schemes in microgrids enhance the utilization of renewable energy resources …

Orbital Angular Momentum Orthogonality-Based Crosstalk Reduction: Theory And Experiment, Unaiza Tariq

Electrical Engineering Theses and Dissertations

Full duplex communication systems allow a single channel to be used for simultaneous two-way communication, increasing spectral efficiency. However, full duplex communication systems suffer from the issue of self-interference between local transmitter and receiver antennas. Analog subtraction and signal processing methods have previously been used to reduce this problem. This dissertation proposes the use of waves carrying orbital angular momentum (OAM) to mitigate the problem of self-interference by offering a means of additional isolation between local antennas.

Orbital angular momentum has been widely studied both in the photonics and radio domain. The theoretically infinite orthogonal states of an OAM signal …

Distribution Network Operation With Solar Photovoltaic And Energy Storage Technology, Mohammad Ramin Feizi

Electrical Engineering Theses and Dissertations

Among distributed energy resources, solar photovoltaic (PV) generation has the largest penetration in the distribution networks. Serving electric vehicles (EV) with renewable resource generation would further reduce the carbon footprint of the energy supply chain for electric vehicles. However, the integration of solar PV and EVs in the unbalanced distribution network introduces several challenges including voltage fluctuations, voltage imbalances, reverse power flow, and protection devices’ malfunctions. The uncertainties associated with solar PV integration and electric vehicles operation require significant effort to develop accurate optimization methodologies in the unbalanced distribution systems operation. In this thesis, in order to cope with the …

Development And Application Of A Design Flow For Photonic Integrated Circuits, Ifeanyi Achu

Electrical Engineering Theses and Dissertations

Silicon photonics allows for the fabrication of many optical elements on a single photonic integrated circuit (PIC). By taking advantage of the established foundry technology used in the CMOS and silicon’s high refractive index, high feature density manufacturing can be achieved in mass quantities. In CMOS fabrication, from conception of an electronic circuit to testing, the process of designing an electronic circuit is dictated by a design flow which has been developed over the course of decades. This flow includes circuit level design and simulation, layout of the circuit, layout and verification of the chip, fabrication, packaging, and testing. Given …

An Investigation Of The Role Of System Effectiveness In The Acquisition And Sustainment Of U.S. Defense Systems: 1958 To 2022, John Green

Operations Research and Engineering Management Theses and Dissertations

This dissertation investigates the role of the system effectiveness methodology in acquiring and sustaining U.S. military weapons systems from 1958 to 2021. The period of interest has seen numerous changes in both the acquisition process and the application of system effectiveness to acquisition and sustainment. Several of the changes were disruptive, including shifting acquisition and sustainment to a commercial paradigm and completely overhauling the approach to acquiring new systems. The method of inquiry integrated three qualitative methods–structured literature review, grounded theory analysis, and historiography–into an innovative approach for investigating the changes to system effectiveness. The database for the investigation was …

The Challenge Of Change, Eric F. Spina

President's Blog: From the Heart

"Some people are book-smart, but lack empathy, kindness and mercy. You cannot go about transforming the world — which is ultimately your assignment when you leave today — without both," President Eric Spina told the Class of 2022 at winter commencement. "As Flyers, you’re called to use your minds and hearts to work across disciplines and differences to make the kind of profound change the world needs."

Effectiveness And Safety Of Direct Oral Anticoagulants Among Patients With Non-Valvular Atrial Fibrillation And Multimorbidity, Amol Dhamane, Mauricio Ferri, Allison V. Keshishian, Cristina Russ, Nipun Atreja, Cynthia Gutierrez, Birol Emir, Huseyin Yuce, Manuela Di Fusco

Publications and Research

Introduction

In the USA, there is a steady rise of atrial fibrillation due to the aging population with increased morbidity. This study evaluated the risk of stroke/systemic embolism (S/SE) and major bleeding (MB) among elderly patients with non-valvular atrial fibrillation (NVAF) and multimorbidity prescribed direct oral anticoagulants (DOACs).

Methods

Using the CMS Medicare database, a retrospective observational study of adult patients with NVAF and multimorbidity who initiated apixaban, dabigatran, or rivaroxaban from January 1, 2012 to December 31, 2017 was conducted. High multimorbidity was classified as having ≥ 6 comorbidities. Cox proportional hazard models were used to evaluate the hazard …

Jam – Winter 2022, Rafat Jan, Edwin Van Teijlingen, Kiran Mubeen, Abeer Musaddique

Journal of Asian Midwives (JAM)

No abstract provided.

Inhibition Of Rad18 By Arsenic, Lindsay B. Volk

Biomedical Sciences ETDs

Arsenite exposure leads to the retention of UV-induced DNA damage, thus burdening translesion synthesis (TLS). Rad18 is an essential factor in initiating TLS through PCNA monoubiquitination and is implicated in homologous recombination. It contains two functionally and structurally distinct zinc fingers that are potential targets for arsenite binding. Results from this study reveal arsenite binding to both zinc fingers of Rad18 and a corresponding loss of domain function. Importantly, arsenite inhibited Rad18 RING-dependent PCNA monoubiquitination and polymerase eta recruitment to DNA damage. Further analysis demonstrated multiple effects of arsenite, including the reduction in the nuclear localization and UV-induced chromatin recruitment …

Surprise Gift Benefits Two Um Programs, Bill Dabney

University of Mississippi News

No abstract provided.

Ela High School Teacher Beliefs About Academic Language Learning, Wendy Aro

Doctorate in Education

The enrollment of English learners (ELs) in K-12 schools in the United States continues to surpass all other student groups reshaping U.S. public schools (National Center for Education Statistics, 2017). Research suggests while learning English, ELs fall behind academically, which can determine how long an EL remains in an English learner program (Wixom, 2014). Educators and leaders are faced with the challenges associated with EL education including professional development, retaining EL specialized teachers, and designing, implementing, and evaluating EL service models. Other challenges include ensuring EL access to grade-level content standards while simultaneously developing the language of the subject area. …

Prioritizing Prosocial Behavior For Preschool Children: How Are Parents Affecting Psb Development?, Deborah Zupito

Doctorate in Education

Scholars and Early Childhood Education (ECE) professionals acknowledge the critical nature of prosocial behavior (PSB) skills in the lives of preschool-aged children. Research specifies that children lacking PSBs are socially and academically disadvantaged. Studies have shown that 30% of preschoolers exhibit negative emotional/social behavior, and 80% of preschool educators report negative social behaviors (NSBs) adversely affecting their jobs. It is well-researched that a child's earliest experiences shape social and emotional behaviors, explicitly parenting and the home environment; however, less research exists about parents' knowledge and perception of their role relating to PSB development in their child's life. This qualitative case …

Lens: A Novel Image Processing-Based Approach For Low-Cost Segmentation Of Computed Tomography Scans Of Lungs, Monica Hinga

Computer Science ETDs

A staggering amount of data has been collected and analyzed since the beginning of the COVID-19 pandemic. Some of that data, however, particularly computed tomography (CT) scans of lungs, are difficult to analyze computationally. Segmentation of COVID-19 lesions provides researchers with insights into where lesions form, their volume, and in the case of time course data, how lesions grow as disease progresses. Spatial information, which has received little attention in the literature, has the potential to provide valuable insight to within-host viral and immune dynamics. Unfortunately, state-of-the-art supervised deep learning methods require labeled data, which can be prohibitively expensive to …