Physical Sciences and Mathematics Commons^™

The Origin, Development, Application, Lessons Learned, And Future Regarding The Bayesian Network Relative Risk Model For Ecological Risk Assessment, Wayne Landis

Institute of Environmental Toxicology & Chemistry Publications

In 2012, a regional risk assessment was published that applied Bayesian networks (BN) to the structure of the relative risk model. The original structure of the relative risk model (RRM) was published in the late 1990s and developed during the next decade. The RRM coupled with a Monte Carlo analysis was applied to calculating risk to a number of sites and a variety of questions. The sites included watersheds, terrestrial systems, and marine environments and included stressors such as nonindigenous species, effluents, pesticides, nutrients, and management options. However, it became apparent that there were limits to the original approach. In …

World Oceans: A Reference Handbook, Rob Tench

Libraries Faculty & Staff Publications

Book review of Newton, David, World Oceans: A Reference Handbook, ABC-CLIO. (Contemporary World Issues), Feb. 2021, ISBN 9781440875434.

Taxonomic And Nutrient Controls On Phytoplankton Iron Quotas In The Ocean, Benjamin S. Twining, Olga Antipova, P. Dreux Chappell, Natalie R. Cohen, Jeremy E. Jacquot, Elizabeth L. Mann, Adrian Marchetti, Daniel C. Ohnemus, Sara Rauschenberg, Alessandro Tagliabue

OES Faculty Publications

Phytoplankton iron contents (i.e., quotas) directly link biogeochemical cycles of iron and carbon and drive patterns of nutrient limitation, recycling, and export. Ocean biogeochemical models typically assume that iron quotas are either static or controlled by dissolved iron availability. We measured iron quotas in phytoplankton communities across nutrient gradients in the Pacific Ocean and found that quotas diverged significantly in taxon‐specific ways from laboratory‐derived predictions. Iron quotas varied 40‐fold across nutrient gradients, and nitrogen‐limitation allowed diatoms to accumulate fivefold more iron than co‐occurring flagellates even under low iron availability. Modeling indicates such “luxury” uptake is common in large regions of …

Marine Phytoplankton Functional Types Exhibit Diverse Responses To Thermal Change, S. I. Anderson, A. D. Barton, Sophie Clayton, S. Dutkiewicz, T. A. Rynearson

OES Faculty Publications

Marine phytoplankton generate half of global primary production, making them essential to ecosystem functioning and biogeochemical cycling. Though phytoplankton are phylogenetically diverse, studies rarely designate unique thermal traits to different taxa, resulting in coarse representations of phytoplankton thermal responses. Here we assessed phytoplankton functional responses to temperature using empirically derived thermal growth rates from four principal contributors to marine productivity: diatoms, dinoflagellates, cyanobacteria, and coccolithophores. Using modeled sea surface temperatures for 1950-1970 and 2080-2100, we explored potential alterations to each group's growth rates and geographical distribution under a future climate change scenario. Contrary to the commonly applied Eppley formulation, our …

First Record Of Blacknape Large-Eye Bream Gymnocranius Satoi (Perciformes: Lethrinidae) In The Philippines, Nicko Amor Flores, Jade Tifany Rey, Jeffrey T. Williams, Kent Carpenter, Mudjekeewis Santos

Biological Sciences Faculty Publications

The Philippines has been regarded as the center of the center of marine shorefish biodiversity, having the highest number of fish species per square area in the world. The blacknape large-eye bream, Gymnocranius satoi, has been reported to occur from Southern Japan, Taiwan to Northwestern Australia and to the Coral Sea, but has not previously been recorded from the Philippines. From 2011 – 2019, the National Fisheries Research and Development Institute (NFRDI) collaborated with the National Museum of Natural History of the Smithsonian Institution (NMNH/SI), USA, and the Old Dominion University (ODU), Virgina, USA, to inventory all commercial fish …

How Wetland Plants Deal With Stress, Taylor M. Sloey

Biological Sciences Faculty Publications

We all get stressed. To deal with that stress, some of us may exercise, take a bubble bath, cry, or simply leave the stressful situation. But how can you cope with stress if you are rooted in place? Plants that live in estuaries are exposed to many types of stresses from the environment, including flooding, high salt levels, low soil oxygen, and waves. Fortunately, wetland plants have developed ways to survive within these conditions, from excreting salt, to growing faster, to even breaking down cell walls to maximize air flow. Plants can tolerate different levels of stress depending on their …

Advancing Applied Research In Conservation Criminology Through The Evaluation Of Corruption Prevention, Enhancing Compliance, And Reducing Recidivism, Jessica S. Kahler, Joseph W. Rivera, Zachary T. Steele, Pilar Morales-Giner, Christian J. Rivera, Carol F. Ahossin, Ashpreet Kaur, Diane J. Episcopio-Sturgeon

Biological Sciences Faculty Publications

Concomitant with an increase in the global illegal wildlife trade has been a substantial increase in research within traditional conservation-based sciences and conservation and green criminology. While the integration of criminological theories and methods into the wildlife conservation context has advanced our understanding of and practical responses to illegal wildlife trade, there remain discrepancies between the number of empirical vs. conceptual studies and a disproportionate focus on a few select theories, geographical contexts, and taxonomic groups. We present three understudied or novel applications of criminology and criminal justice research within the fields of fisheries, forestry, and wildlife conservation. First, we …

Stratospheric Fluorine As A Tracer Of Circulation Changes: Comparison Between Infrared Remote-Sensing Observations And Simulations With Five Modern Reanalyses, M. Prignon, S. Chabrillat, M. Friedrich, D. Smale, S. E. Strahan, Peter F. Bernath, M. P. Chipperfield, S. S. Dhomse, W. Feng, D. Minganti, C. Servais, E. Mahieu

Chemistry & Biochemistry Faculty Publications

Using multidecadal time series of ground-based and satellite Fourier transform infrared measurements of inorganic fluorine (i.e., total fluorine resident in stratospheric fluorine reservoirs), we investigate stratospheric circulation changes over the past 20 years. The representation of these changes in five modern reanalyses is further analyzed through chemical-transport model (CTM) simulations. From the observations but also from all reanalyses, we show that the inorganic fluorine is accumulating less rapidly in the Southern Hemisphere than in the Northern Hemisphere during the 21st century. Comparisons with a study evaluating the age-of-air of these reanalyses using the same CTM allow us to link this …

Pothole Detection Under Diverse Conditions Using Object Detection Model, Ibrahim Hassan Syed, Dympna O'Sullivan, Susan Mckeever

Datasets

One of the most important tasks in road maintenance is the detection of potholes. This process is usually done through manual visual inspection, where certified engineers assess recorded images of pavements acquired using cameras or professional road assessment vehicles. Machine learning techniques are now being applied to this problem, with models trained to automatically identify road conditions. However, approaching this real-world problem with machine learning techniques presents the classic problem of how to produce generalizable models. Images and videos may be captured in different illumination conditions, with different camera types, camera angles and resolutions. In this paper we present our …

Developing A Machine Learning Framework For Upwind Surveyed Regions, Witenberg Santiago Rodrigues Souza

Graduate Research Theses & Dissertations

Every year, the Oil & Gas industry loses $2B dollars due to fugitive natural gas leaks. Identifying the source of a leak is a complex challenge, especially in suburban areas where gas leakage may be mixed with other sources. Besides the multitude of possible locations for a leak in an urban area, surveying an entire city may take considerable time and funds depending on the chosen method. This work proposes a framework based on unmanned areal vehicles (UAV) to survey a region for gas leaks. To accomplish this goal, we rely on the concept of a Upwind Survey Region (USR). …

Diversity And Taxonomy Of Malagasy Pygmy Hippopotamuses, Allison Shackelton

Graduate Research Theses & Dissertations

Madagascar has many species of extinct megafauna, including up to three species of extinct hippopotamus. Subfossil hippo specimens have been found at sites across Madagascar, yet the number of species and taxonomic relationships of the extinct Malagasy pygmy hippopotamus are poorly understood. This thesis will analyze cranial and postcranial bones to improve our understanding of the diversity and taxonomy of Malagasy subfossil hippos, focusing on adults from Ampasambazimba and Tsaramody and juveniles from Ampasambazimba and Anjohibe. Measurements of the tibia and femur of adult specimens, which are used as diagnostic features in other studies, may not be accurate diagnostic features, …

Alteration Reactions In A Hornblende-Biotite-Anthophyllite-Fluid System: Implications For Cu-Au Ore Deposits, James Mitchell Lightner

Graduate Research Theses & Dissertations

High-grade porphyry Cu-Au ore deposits are typically contained in the potassic alteration zone, which forms through the alteration of preexisting country rock by a magmatic volatile phase (MVP) exsolved from an igneous intrusion. The MVP is a H2O dominant phase that contains high concentrations of NaCl, KCl, FeCl2, HCl, sulfur (as H2S or SO2) and minor concentrations of metals. The minerals in the potassic alteration zone are predominantly K-feldspar and biotite with a shreddy texture. Shreddy biotite forms from the replacement of prismatic-tabular shaped hornblende crystals, resulting in a characteristic shreddy texture. The alteration of hornblende to biotite can neutralize …

Weather-Related Carbon Monoxide Poisoning In The United States: 2000-2019, Bailey Raine Stevens

Graduate Research Theses & Dissertations

Carbon monoxide (CO) is a colorless, odorless gas that can cause injury or death if inhaled. CO is a frequent secondary hazard induced by the aftereffects of natural hazards as individuals, families, and communities will often seek alternative power sources for heating, cooking, lighting, and cleanup during the emergency and recovery phases of a disaster. These alternative power sources – such as generators, petrol heaters, and vehicles, exhaust CO – can ultimately build to toxic levels in enclosed areas. Ever-increasing environmental and societal changes combined with an aging infrastructure are increasing the odds of power failures during hazardous weather events, …

Some Special Cases Of The Andrews-Bowman Continued Fraction, Bryan Thomas Zollinger

Graduate Research Theses & Dissertations

One of the most famous results from q-series is that of the Rogers-Ramanujan continued fraction, given by [special characters omitted]. G.E. Andrews and D. Bowman gave a full extension of this continued fraction using G.N. Watson’s nonterminating very well-poised 8φ7 function. As opposed to Ramanujan’s generalization that only used four variables, this generalization is given in seven variables, and certain q-series identities naturally arise from it. As a special case of their theorem, Andrews and Bowman gave the following identity: [special characters omitted]. This thesis will give a full proof of Andrews and Bowman’s result, as well as investigate other …

Miocene-Pleistocene Diatom Oxygen Isotope And Biogenic Silica Record From Iodp Site U1523, Ross Sea, Antarctica, Donald James Mclennan

Graduate Research Theses & Dissertations

The West Antarctic Ice Sheet (WAIS) plays a significant role in Earth’s climate. WAIS is currently retreating due to changes in wind-driven oceanic currents resulting in an increasing flux of warm waters to ice margins. Brine rejection in the Ross Sea is also major source of High Salinity Shelf water (HSSW) and Antarctica Bottom Waters (AABW), which creates a stratified ocean and plays a significant role in regulating Earth’s climate. Currently, there are very limited proxies that can quantify the variable input of HSSW formation on geologic time scales. Here we provide a 18Odiatom and biogenic silica (BSi) record which …

Traffic Fatality Rate Prediction Based On Deep Neural Network And Bayesian Neural Network, Yiqun Hu

Graduate Research Theses & Dissertations

There have been numerous studies on traffic accidents and their fatality rate. For this challenging machine learning regression problem, Neural Networks (NNs) have produced state-of-the-art data. Despite their success, they are often used in a fre- quentist scheme, which means they cannot account for uncertainty in their forecasts. BNNs are comprised of a Probabilistic Model and a Neural Network. The aim of such a design is to bring together the benefits of Neural Networks and stochastic modeling. Neural networks have the ability to approximate continuous functions uni- versally. Statistical models allow for the direct definition of a model with known …

Geometric Properties Of Representation Varieties For An Elementary Abelian Group Of Rank 2 In Positive Characteristic, Eric Johnson

Graduate Research Theses & Dissertations

This dissertation’s motivation is the exploration of the irreducible components of Repn(kG), the affine variety whose points are n-dimensional representations of a finite group G over a field k. We let G = Z/pZ×Z/pZ and assume k is algebraically closed with char(k) = p > 0. In this case there is an isomorphism of affine varieties φ : Repn (kG) → C nil 1 (n) where C nil 1 (n) = {(x, y) Mn(k)×Mn(k) | x p = y p = xy−yx = 0}. Hence, for an irreducible component X of Repn (kG), φ(X) is an irreducible component of C nil …

Hydrocarbons In The Niobrara Formation, Powder River Basin, Northeast Wyoming, From Geophysical Well Logs, Jennifer Shilo James

Graduate Research Theses & Dissertations

The Powder River Basin, located in Wyoming, is a moderate producer of hydrocarbons with production hovering around 100 million barrels of oil per year. Recently the Niobrara Formation has garnered attention for hydrocarbon exploration and production using both conventional and unconventional drilling. A quick-look method for evaluating organic content, using either existing or real time data sets gathered from geophysical well logs, provides an opportunity to rapidly, accurately, and economically assess the formation’s organic content and thus hydrocarbon bearing potential. The popular Schmoker method determines organic content by relating gamma ray intensity to formation density. It has been successfully employed …

Robust Determinants Of Happiness: High-Dimensional Bayesian Treatment Of Model Uncertainty, Milivoje Davidovic

Graduate Research Theses & Dissertations

The thesis investigates the most relevant economic and institutional determinants of happiness in some 93 countries worldwide, covering the period 2006-2019. We employ the Bayesian Model Averaging (BMA) fixed effect model (country demeaned and time demeaned) using a working panel data set with 651 observations. Our initial goal is to address the problem of model uncertainty in panel data models of happiness, aiming at selecting a set variables that are likely to be included in as "true" model of happiness. In addition, we aim to investigate the causal relationship running from selected economic and institutional variable to index of happiness. …

The Relevance Of Credit Risk In The Determination Of Commercial Banks’ Profitability: Evidence From Ghana, Godwin Kwabla Ekpe

Graduate Research Theses & Dissertations

Existing empirical literature on the relationship between credit risk and bank’s profitability is replete with mixed results. This research investigates the probable effect of credit risk on banks’ profitability by examining the nature of the relationship between two measures of credit risk (Loss provisioning rate and Actual provisioning charge rate) and two measures ofprofitability (Return on assets and Return on Equity). The investigation is conducted using data on the Ghanaian banking industry. Various modeling techniques are used to fit the data, including frequentist beta regression and Bayesian beta regression models. The results across all models suggest negative linear relationship between …

Pumping Fees And Spillovers In The Groundwater Commons: An Evaluation Of A Conservation Tool And Irrigator Competitive Behavior, Godwin Kwabla Ekpe

Graduate Research Theses & Dissertations

My dissertation examines the effectiveness of pumping fees in groundwater commons agricultural irrigation as a conservation tool in the presence of varying water scarcity levels and spatial interdependence among irrigators. The first chapter provides a brief overview of three important areas of groundwater commons irrigation addressed in this dissertation. The second chapter’s objectives are two-fold. First, I review the common-pool resources literature relative to concerns of sustainable extraction and implementation of conservation policies focusing on pricing incentives in the management of groundwater commons where irrigators share the same underlying aquifer. Second, I introduce a theoretical model involving incorporating a non-constant …

An Investigation Of Endangered And Threatened Plants Using Phylogenomics, Phylogenetic Metrics, And Geography To Prevent Species Loss, Phyllis H. Pischl

Graduate Research Theses & Dissertations

The conservation of endangered and threatened plant species plays an integral part of preserving biodiversity. Loss of habitat is one of the main reasons that plants become endangered or threatened. In Illinois much of the native habitat has been lost to the conversion of industry, agriculture and urban areas. The goals of this dissertation are to 1) determine where endangered and threatened species are finding habitats in relation to land use, 2) produce a robust phylogeny of endangered and threatened species of grasses and apply phylogenetic diversity analysis to better understand the plight of these species, and 3) use climate …

Beam Phase Space Diagnostic Techniques Along The Fermilab Muon Campus Extraction Line, Benjamin Simons

Graduate Research Theses & Dissertations

The pursuit of physics beyond the Standard Model relies on the ability to make highly sensitive measurements with a high level of precision. Particle accelerators have been a cornerstone for the foundation of tools that have allowed us to continue to probe the limits of what the Standard Model can predict.

This thesis is focused on applying various measurement techniques, some standard and one not so standard, that provide crucial information about beam optics and beam quality for the purposes of monitoring the beam as it is guided throughout a beam transport system. After the measuring techniques have been described, …

Clinical Applications And Feasibility Of Proton Ct And Proton Radiography, Christina Marie Sarosiek

Graduate Research Theses & Dissertations

Proton therapy is a form of radiation treatment for cancer that utilizes the Bragg peak to create conformal high dose regions around the tumor volume. However, the use of x-ray computed tomography (CT) and x-ray radiography for treatment planning and pre-treatment quality assurance procedures improves the achievable effectiveness of proton treatment plans (using proton CT) and the pretreatment verification (using proton radiography). Errors in the conversion from x-ray Hounsfield units (HU) to proton relative stopping powers (RSP) leads to errors in the predicted proton range. To account for the errors, 3.5% margins are included in the treatment plan. This means …

Steepest Descent, Elastic Energy, And Stability In Infinite Dimensional Hilbert Manifolds, Scott W. Rexford

Graduate Research Theses & Dissertations

Consider constant-speed planar curves $\gamma =(x,y):[0,1]\to\mathbb{R}^2$ subject to $\gamma (0)=(0,0)$ and a prescribed value of $x(1)$, but with $y(1)$ unconstrained. We analyze the existence and the stability of critical curves of the elastic energy. Elastic curves are here thought of as points in an infinite-dimensional Sobolev manifold where the intrinsic gradient of the elastic energy vanishes. The admissible curves subject to constraints are members of a Riemannian submanifold using the ambient metric. A curve is stable with respect to the negative gradient flow if it is global or local minimum, and unstable otherwise. We analyze the stability of the classical …

Bayesian Tail Probability Estimation And Model Selection, Nan Shen

Graduate Research Theses & Dissertations

Bayesian statistics is a prevalent and important field in statistics that assigns Bayesian probabilities, which represent a state of knowledge, to unknown quantities. We study Bayesian statistics with its applications through two projects in this report.

In the first project, we investigate the reasons that the Bayesian estimator of the tail probability is always higher than the frequentist estimator. Sufficient conditions for this phenomenon are established by looking at Taylor series approximations about the tail and by using Jensen's Inequality, both of which point to the convexity of the distribution function.

The second project is about redefining the Bayesian information …

Electrochemical Study Of The Performance Of Manganese Vanadium Oxide Cathodes In Zinc Batteries, Sarat Alabidun

Graduate Research Theses & Dissertations

Zinc metal batteries are considered a promising alternative for grid energy storage due to the low redox potential (-0.76V vs SHE) and high theoretical specific capacity (850mAh/g) of zinc metal anode as well as its compatibility with aqueous electrolytes. They however face issues of poor cathode stability and rapid capacity fading. Several methods have been devised to improve the stability of the cathode materials and develop novel cathode materials with better performance including the metal ion doping of intercalation materials.This study investigated the performance of zinc metal batteries with novel manganese vanadium oxide cathodes. Organic structure directing agents have been …

Characterization Of Potential Anti-Infective Agents By Targeting Burkholderia Pseudomallei And Escherichia Coli Ispf, Dakota Lane Grote

Graduate Research Theses & Dissertations

With the likelihood of contracting an antibiotic resistant infection increasing, the need for novel anti-infective agents is critical. The development of novel anti-infective agents benefits from the identification of new target pathways necessary for the survival of the pathogen. One such target is the methylerythritol phosphate (MEP) pathway, responsible for the synthesis of the isoprenoid precursors isopentyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP) in bacteria and other pathogenic organisms. The MEP pathway is an attractive target because it is specific to a wide range of pathogenic organisms, while humans have a separate pathway, the mevalonate (MVA) pathway, for the biosynthesis …

Trends In Observed And Simulated Radar Reflectivity For The 21st Century, Christopher Michael Battisto

Graduate Research Theses & Dissertations

The effects of climate change may influence the prevalence of regional atmospheric conditions supportive of hazardous convective weather (HCW). As a result, the possibility of an increase in the frequency, strength, and/or variability of thunderstorms and their high-impact hazards—including tornadoes, damaging winds, hail, and flash flood-producing downpours—has garnered much scientific and public interest. Radar reflectivity, which remotely assesses precipitation intensity, may be used to detect, track, catalog, and appraise HCW and their parent storms over broad spatiotemporal scales. Reflectivity may also be simulated with regional climate models, and recent, but limited, efforts using these simulation output have identified the potential …

Investigation Of Spontaneously Patterned Nanoporous Organosilicate Thin Film Channels For Liquid Chromatography Applications., Ashwin Sanjay Bhaskaran

Graduate Research Theses & Dissertations

Microscale devices are attractive options for the advancement of biomedical engineering and life science. They have huge potential in the pharmaceutical and biomedical fields provided the critical factors such as device size, product purity and efficiency are not a hindrance. In most cases, traditional microelectronics fabrication processes are quite costly and complicated. By improving on them, their application in fields such as chemical sensing, detection and analysis is possible. By implementing this on a chip, we can reduce the cost and improve portability. This thesis focuses on the investigation of a novel class of spontaneously patterned nanoporous organosilicate nanoparticle-based films …