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Full-Text Articles in Physical Sciences and Mathematics

Categorizing A Continuous Predictor Subject To Measurement Error, Betsabé G. Blas Achic, Tianying Wang, Ya Su, Victor Kipnis, Kevin Dodd, Raymond J. Carroll Jan 2018

Categorizing A Continuous Predictor Subject To Measurement Error, Betsabé G. Blas Achic, Tianying Wang, Ya Su, Victor Kipnis, Kevin Dodd, Raymond J. Carroll

Statistics Faculty Publications

Epidemiologists often categorize a continuous risk predictor, even when the true risk model is not a categorical one. Nonetheless, such categorization is thought to be more robust and interpretable, and thus their goal is to fit the categorical model and interpret the categorical parameters. We address the question: with measurement error and categorization, how can we do what epidemiologists want, namely to estimate the parameters of the categorical model that would have been estimated if the true predictor was observed? We develop a general methodology for such an analysis, and illustrate it in linear and logistic regression. Simulation studies are …


The [Cii] 158ΜM Line Emission In High-Redshift Galaxies, Guilaine Lagache, Morgane Cousin, Marios Chatzikos Jan 2018

The [Cii] 158ΜM Line Emission In High-Redshift Galaxies, Guilaine Lagache, Morgane Cousin, Marios Chatzikos

Physics and Astronomy Faculty Publications

Gas is a crucial component of galaxies, providing the fuel to form stars, and it is impossible to understand the evolution of galaxies without knowing their gas properties. The [CII] fine structure transition at 158 μm is the dominant cooling line of cool interstellar gas, and is the brightest of emission lines from star forming galaxies from FIR through metre wavelengths, almost unaffected by attenuation. With the advent of ALMA and NOEMA, capable of detecting [CII]-line emission in high-redshift galaxies, there has been a growing interest in using the [CII] line as a probe of the physical conditions of …


Ground Motions Induced By The March 11, 2018, Implosion Of The Capital Plaza Tower, Frankfort, Kentucky, N. Seth Carpenter, Michael J. Lynch, Brandon C. Nuttall, Zhenming Wang, Andrew S. Holcomb Jan 2018

Ground Motions Induced By The March 11, 2018, Implosion Of The Capital Plaza Tower, Frankfort, Kentucky, N. Seth Carpenter, Michael J. Lynch, Brandon C. Nuttall, Zhenming Wang, Andrew S. Holcomb

Report of Investigations--KGS

The demolition by implosion of the Capital Plaza Tower in downtown Frankfort provided an opportunity to record seismic waves from a known source of seismic energy in order to observe local ground-motion amplification and resonance within the underlying unconsolidated sediment. The Kentucky Geological Survey deployed three strong-motion accelerographs at approximately equal distances around the tower to record ground motions induced by its collapse. The KGS instruments were installed at sites with different underlying geology: one on bedrock and two on Kentucky River Valley unconsolidated sediments.

Using images captured by a high-speed video camera, with timing synchronized with the clock of …


Aggressive Diuresis And Severity-Adjusted Length Of Hospital Stay In Acute Congestive Heart Failure Patients, Muhammad U. Butt Jan 2018

Aggressive Diuresis And Severity-Adjusted Length Of Hospital Stay In Acute Congestive Heart Failure Patients, Muhammad U. Butt

Theses and Dissertations--Clinical Research Design

To see if aggressive diuresis in first twenty four hours is associated with a comparable number of total days in the hospital as compared to non-aggressive diuresis. In this retrospective cohort study, we compared the length of hospital stay of consecutive patients admitted in one year based on their diuresis during the first twenty-four hours of hospitalization: aggressive diuresis (group 1) i.e. > 2400mL versus non-aggressive diuresis (group 2) i.e. ≤ 2400mL urine output. Patients were excluded if in cardiogenic shock, had creatinine level above 3 mg/dL on admission, or on dialysis. A total of 194 patients were enrolled (29 in …


A Multi-Indicator Approach To Understanding The Diagenesis Of Carbonates In Pennsylvanian Mudrocks Of The Midland Basin, Alex J. Reis Jan 2018

A Multi-Indicator Approach To Understanding The Diagenesis Of Carbonates In Pennsylvanian Mudrocks Of The Midland Basin, Alex J. Reis

Theses and Dissertations--Earth and Environmental Sciences

The Late Pennsylvanian was a time of frequent, rapid glacioeustatic sea-level changes. These changes were recorded in the Wolfcamp D Formation of the Midland Basin as a series of cyclothems similar to those studied in the Midcontinent region (e.g., Algeo and Heckel, 2008). This study focuses on identifying the mechanisms and controls on carbonate deposition and diagenesis through the Upper Pennsylvanian Wolfcamp D Formation and evaluating the potential for these layers to be stratigraphically significant. A stepwise progression of diagenetic processes was identified through the use of δ13Ccarb and δ18Ocarb, bulk geochemical and …


Microrna Expression Patterns In Human Anterior Cingulate And Motor Cortex: A Study Of Dementia With Lewy Bodies Cases And Controls, Peter T. Nelson, Wang-Xia Wang, Sarah A. Janse, Katherine L. Thompson Jan 2018

Microrna Expression Patterns In Human Anterior Cingulate And Motor Cortex: A Study Of Dementia With Lewy Bodies Cases And Controls, Peter T. Nelson, Wang-Xia Wang, Sarah A. Janse, Katherine L. Thompson

Sanders-Brown Center on Aging Faculty Publications

Overview

MicroRNAs (miRNAs) have been implicated in neurodegenerative diseases including Parkinson’s disease and Alzheimer’s disease (AD). Here, we evaluated the expression of miRNAs in anterior cingulate (AC; Brodmann area [BA] 24) and primary motor (MO; BA 4) cortical tissue from aged human brains in the University of Kentucky AD Center autopsy cohort, with a focus on dementia with Lewy bodies (DLB).

Methods

RNA was isolated from gray matter of brain samples with pathology-defined DLB, AD, AD+DLB, and low-pathology controls, with n=52 cases initially included (n=23 with DLB), all with low (<4hrs) postmortem intervals. RNA was profiled using Exiqon miRNA microarrays. Quantitative PCR for post-hoc replication was performed on separate cases (n=6 controls) and included RNA isolated from gray matter of MO, AC, primary somatosensory (BA 3), and dorsolateral prefrontal (BA 9) cortical regions.

Results

The miRNA expression patterns differed substantially according to …


Bivariate Generalization Of The Time-To-Event Conditional Reassessment Method With A Novel Adaptive Randomization Method, Donglin Yan Jan 2018

Bivariate Generalization Of The Time-To-Event Conditional Reassessment Method With A Novel Adaptive Randomization Method, Donglin Yan

Theses and Dissertations--Epidemiology and Biostatistics

Phase I clinical trials in oncology aim to evaluate the toxicity risk of new therapies and identify a safe but also effective dose for future studies. Traditional Phase I trials of chemotherapies focus on estimating the maximum tolerated dose (MTD). The rationale for finding the MTD is that better therapeutic effects are expected at higher dose levels as long as the risk of severe toxicity is acceptable. With the advent of a new generation of cancer treatments such as the molecularly targeted agents (MTAs) and immunotherapies, higher dose levels no longer guarantee increased therapeutic effects, and the focus has shifted …


Improved Methods And Selecting Classification Types For Time-Dependent Covariates In The Marginal Analysis Of Longitudinal Data, I-Chen Chen Jan 2018

Improved Methods And Selecting Classification Types For Time-Dependent Covariates In The Marginal Analysis Of Longitudinal Data, I-Chen Chen

Theses and Dissertations--Epidemiology and Biostatistics

Generalized estimating equations (GEE) are popularly utilized for the marginal analysis of longitudinal data. In order to obtain consistent regression parameter estimates, these estimating equations must be unbiased. However, when certain types of time-dependent covariates are presented, these equations can be biased unless an independence working correlation structure is employed. Moreover, in this case regression parameter estimation can be very inefficient because not all valid moment conditions are incorporated within the corresponding estimating equations. Therefore, approaches using the generalized method of moments or quadratic inference functions have been proposed for utilizing all valid moment conditions. However, we have found that …


Using Prescription Drug Monitoring Data To Inform Population Level Analysis Of Opioid Analgesic Utilization, Huong T. T. Luu Jan 2018

Using Prescription Drug Monitoring Data To Inform Population Level Analysis Of Opioid Analgesic Utilization, Huong T. T. Luu

Theses and Dissertations--Epidemiology and Biostatistics

Increased opioid analgesic (OA) prescribing has been associated with increased risk of prescription opioid diversion, misuse, and abuse. States established prescription drug monitoring programs (PDMPs) to collect and analyze electronic records for dispensed controlled substances to reduce prescription drug abuse and diversion. PDMP data can be used by prescribers for tracking patient’s history of controlled substance prescribing to inform clinical decisions.

The studies in this dissertation are focused on the less utilized potential of the PDMP data to enhance public health surveillance to monitor OA prescribing and co-prescribing and association with opioid overdose mortality and morbidity. Longitudinal analysis of OA …


Zircon U-Pb Geochronology Of Two Basement Cores (Kentucky, Usa): Implications For Late Mesoproterozoic Sedimentation And Tectonics In The Eastern Midcontinent, David P. Moecher, J. Richard Bowersox, John B. Hickman Jan 2018

Zircon U-Pb Geochronology Of Two Basement Cores (Kentucky, Usa): Implications For Late Mesoproterozoic Sedimentation And Tectonics In The Eastern Midcontinent, David P. Moecher, J. Richard Bowersox, John B. Hickman

Earth and Environmental Sciences Faculty Publications

Basement cores from two wells drilled west and east of the Grenville front consist of feldspathic litharenite and granitic orthogneiss, respectively. Detrital zircon U-Pb ages for the litharenite define a broad dominant U-Pb age mode at ca. 1115 Ma. The dominant mode matches that for the type locality of the Middle Run Formation in the Ohio subsurface and is interpreted to consist of detrital zircons sourced from East Continent Rift volcanic sources (ca. 1100 Ma) and Grenville Shawinigan granites/gneisses (1120–1180 Ma). The youngest detrital zircon ages (ca. 1020 Ma) require a maximum depositional age that is at least 70 My …


Ultra-Fast And Memory-Efficient Lookups For Cloud, Networked Systems, And Massive Data Management, Ye Yu Jan 2018

Ultra-Fast And Memory-Efficient Lookups For Cloud, Networked Systems, And Massive Data Management, Ye Yu

Theses and Dissertations--Computer Science

Systems that process big data (e.g., high-traffic networks and large-scale storage) prefer data structures and algorithms with small memory and fast processing speed. Efficient and fast algorithms play an essential role in system design, despite the improvement of hardware. This dissertation is organized around a novel algorithm called Othello Hashing. Othello Hashing supports ultra-fast and memory-efficient key-value lookup, and it fits the requirements of the core algorithms of many large-scale systems and big data applications. Using Othello hashing, combined with domain expertise in cloud, computer networks, big data, and bioinformatics, I developed the following applications that resolve several major …


Deep Neural Networks For Multi-Label Text Classification: Application To Coding Electronic Medical Records, Anthony Rios Jan 2018

Deep Neural Networks For Multi-Label Text Classification: Application To Coding Electronic Medical Records, Anthony Rios

Theses and Dissertations--Computer Science

Coding Electronic Medical Records (EMRs) with diagnosis and procedure codes is an essential task for billing, secondary data analyses, and monitoring health trends. Both speed and accuracy of coding are critical. While coding errors could lead to more patient-side financial burden and misinterpretation of a patient’s well-being, timely coding is also needed to avoid backlogs and additional costs for the healthcare facility. Therefore, it is necessary to develop automated diagnosis and procedure code recommendation methods that can be used by professional medical coders.

The main difficulty with developing automated EMR coding methods is the nature of the label space. The …


Geochronological And Geochemical Constraints On The Origin Of The Cartoogechaye Terrane, Western North Carolina: Implications For The Late Precambrian To Early Paleozoic Evolution Of The Eastern Laurentian Margin, Kevin B. Walsh Jr. Jan 2018

Geochronological And Geochemical Constraints On The Origin Of The Cartoogechaye Terrane, Western North Carolina: Implications For The Late Precambrian To Early Paleozoic Evolution Of The Eastern Laurentian Margin, Kevin B. Walsh Jr.

Theses and Dissertations--Earth and Environmental Sciences

The Cartoogechaye terrane (CT) is an enigmatic migmatite terrane within the Central Blue Ridge province of the southern Appalachians. Previous work identified exotic Pb isotope compositions within the CT (Quinn, 2012). More recent studies that mapped the extent of potentially exotic metaigneous lithologies yield U-Pb zircon ages consistent with a native Laurentian margin metasedimentary origin (Larkin, 2016). This study focused on the possible extent of similar lithologies in the Clyde quadrangle and provides further constraints on the crustal affinity of the CT. The Clyde quadrangle consists of four distinct lithologic packages: the CT, Ashe metamorphic suite, Great Smoky Group, and …


Applied Temperament, Geoffrey D. Hershberger Jan 2018

Applied Temperament, Geoffrey D. Hershberger

Theses and Dissertations--Music

The following document was created in order to promote intonation consensus in ensembles and to better facilitate learning in educational settings. Non-keyboard instruments provide musicians an opportunity to make nearly infinitesimal adjustments to pitch while performing; this creates difficulties for students and challenges even the most seasoned professionals. Non-keyboard musicians struggle their whole lives to play in tune, and even when one knows exactly where they want to place a pitch, technical difficulties can foul any musician's performance. When performing solo, the musician must choose a tuning system that is suitable for the music being performed, and attempt to realize …


Surficial Geologic Map Of The Newport 7.5-Minute Quadrangle, Kentucky, Matthew Massey, Antonia E. Bottoms, Maxwell L. Hammond Iii Jan 2018

Surficial Geologic Map Of The Newport 7.5-Minute Quadrangle, Kentucky, Matthew Massey, Antonia E. Bottoms, Maxwell L. Hammond Iii

Contract Reports--KGS

The Newport 7.5-minute quadrangle is located in the Outer Bluegrass physiographic province (McFarlan, 1943) in the Greater Cincinnati metropolitan area of northern Kentucky and includes parts of Kenton and Campbell Counties. Topography is characterized by a relatively broad expanse of upland with moderate relief that is bounded by the Ohio River Valley, Licking River Valley, and Fourmile Creek. Gibbons (1973) mapped the bedrock geology of this quadrangle, which was later digitized by Sparks (2002). The entire quadrangle is underlain by horizontal Ordovician limestone and shale, consisting of the Point Pleasant Formation, Kope Formation, Fairview Formation, Bellevue Tongue of the Grant …


Surficial Geologic Map Of The Rising Sun 7.5-Minute Quadrangle, Kentucky, Steven L. Martin, Antonia E. Bottoms, Maxwell L. Hammond Iii Jan 2018

Surficial Geologic Map Of The Rising Sun 7.5-Minute Quadrangle, Kentucky, Steven L. Martin, Antonia E. Bottoms, Maxwell L. Hammond Iii

Contract Reports--KGS

The Rising Sun 7.5-minute quadrangle is located in northern Kentucky in the Outer Bluegrass physiographic province (McFarlan, 1943). The area is underlain by Upper Ordovician limestone and shale, and is characterized by low- to medium-relief topography. The oldest rock unit in the quadrangle is the Point Pleasant Formation, which consists of interbedded limestone and shale, and is exposed at the base of the bedrock uplands area south of Lower East Bend Bottom. The shale-dominated Kope Formation overlying the Point Pleasant Formation is exposed in most stream channels and underlies the valleys and hillslopes in the quadrangle. The Kope Formation is …


Kentucky Water Resources Research Institute Annual Technical Report Fy 2017, Kentucky Water Resources Research Institute, University Of Kentucky Jan 2018

Kentucky Water Resources Research Institute Annual Technical Report Fy 2017, Kentucky Water Resources Research Institute, University Of Kentucky

KWRRI Annual Technical Reports (USGS’s 104b Grant Program)

The 2017 Annual Technical Report for Kentucky consolidates reporting requirements for the Section 104(b) base grant award into a single document that includes: 1) a synopsis of each student research enhancement project that was conducted during the period, 2) citations for related publications, reports, and presentations, 3) a description of information transfer activities, 4) a summary of student support during the period, and 5) notable awards and achievements.

No funds were requested for general program administration activities. However, travel funds were provided to support the participation of the director and associate director in the annual meeting of the National Institutes …


A Recurrent Neural Network Architecture For Biomedical Event Trigger Classification, Jeevith Bopaiah Jan 2018

A Recurrent Neural Network Architecture For Biomedical Event Trigger Classification, Jeevith Bopaiah

Theses and Dissertations--Computer Science

A “biomedical event” is a broad term used to describe the roles and interactions between entities (such as proteins, genes and cells) in a biological system. The task of biomedical event extraction aims at identifying and extracting these events from unstructured texts. An important component in the early stage of the task is biomedical trigger classification which involves identifying and classifying words/phrases that indicate an event. In this thesis, we present our work on biomedical trigger classification developed using the multi-level event extraction dataset. We restrict the scope of our classification to 19 biomedical event types grouped under four broad …


Hydrologic Monitoring And 2-D Electrical Resistivity Imaging For Joint Geophysical And Geotechnical Characterization Of Shallow Colluvial Landslides, Matthew M. Crawford Jan 2018

Hydrologic Monitoring And 2-D Electrical Resistivity Imaging For Joint Geophysical And Geotechnical Characterization Of Shallow Colluvial Landslides, Matthew M. Crawford

Theses and Dissertations--Earth and Environmental Sciences

Landslide characterization and hazard assessments require multidisciplinary approaches that connect geologic processes with geotechnical parameters. Field monitoring of hydrologic variables such as water content and water potential, coupled with geoelectrical measurements that can establish relationships used for geotechnical and landslide hazard investigations is deficient.

This study brings together different techniques to develop a methodology that connects geoelectrical measurements and shear strength. A field-based framework was established that includes (1) analysis of long-term soil moisture fluctuations within different landslides (2) establishment of constitutive and new equations that test the use of electrical conductivity to predict soil-water relationships and shear strength (3) …


Improving In-Stream Nutrient Routines In Water Quality Models Using Stable Isotope Tracers: A Review And Synthesis, Alexandria K. Jensen, William I. Ford, James F. Fox, Admin Husic Jan 2018

Improving In-Stream Nutrient Routines In Water Quality Models Using Stable Isotope Tracers: A Review And Synthesis, Alexandria K. Jensen, William I. Ford, James F. Fox, Admin Husic

Biosystems and Agricultural Engineering Faculty Publications

Water quality models serve as an economically feasible alternative to quantify fluxes of nutrient pollution and to simulate effective mitigation strategies; however, their applicability is often questioned due to broad uncertainties in model structure and parameterization, leading to uncertain outputs. We argue that reduction of uncertainty is partially achieved by integrating stable isotope data streams within the water quality model architecture. This article outlines the use of stable isotopes as a response variable within water quality models to improve the model boundary conditions associated with nutrient source provenance, constrain model parameterization, and elucidate shortcomings in the model structure. To assist …


Leveraging Overhead Imagery For Localization, Mapping, And Understanding, Scott Workman Jan 2018

Leveraging Overhead Imagery For Localization, Mapping, And Understanding, Scott Workman

Theses and Dissertations--Computer Science

Ground-level and overhead images provide complementary viewpoints of the world. This thesis proposes methods which leverage dense overhead imagery, in addition to sparsely distributed ground-level imagery, to advance traditional computer vision problems, such as ground-level image localization and fine-grained urban mapping. Our work focuses on three primary research areas: learning a joint feature representation between ground-level and overhead imagery to enable direct comparison for the task of image geolocalization, incorporating unlabeled overhead images by inferring labels from nearby ground-level images to improve image-driven mapping, and fusing ground-level imagery with overhead imagery to enhance understanding. The ultimate contribution of this thesis …


Random Models Of Very Hard 2qbf And Disjunctive Programs: An Overview, Giovanni Amendola, Francesco Ricca, Miroslaw Truszczynski Jan 2018

Random Models Of Very Hard 2qbf And Disjunctive Programs: An Overview, Giovanni Amendola, Francesco Ricca, Miroslaw Truszczynski

Computer Science Faculty Publications

We present an overview of models of random quantified boolean formulas and their natural random disjunctive ASP program counter-parts that we have recently proposed. The models have a simple structure but also theoretical and empirical properties that make them useful for further advancement of the SAT, QBF and ASP solvers.


Exploring Spatial And Temporal Variability Of Soil And Crop Processes For Irrigation Management, Javier Reyes Jan 2018

Exploring Spatial And Temporal Variability Of Soil And Crop Processes For Irrigation Management, Javier Reyes

Theses and Dissertations--Plant and Soil Sciences

Irrigation needs to be applied to soils in relatively humid regions such as western Kentucky to supply water for crop uptake to optimize and stabilize yields. Characterization of soil and crop variability at the field scale is needed to apply site specific management and to optimize water application. The objective of this work is to propose a characterization and modeling of soil and crop processes to improve irrigation management. Through an analysis of spatial and temporal behavior of soil and crop variables the variability in the field was identified. Integrative analysis of soil, crop, proximal and remote sensing data was …


Multifactor Dimensionality Reduction With P Risk Scores Per Person, Ye Li Jan 2018

Multifactor Dimensionality Reduction With P Risk Scores Per Person, Ye Li

Theses and Dissertations--Statistics

After reviewing Multifactor Dimensionality Reduction(MDR) and its extensions, an approach to obtain P(larger than 1) risk scores is proposed to predict the continuous outcome for each subject. We study the mean square error(MSE) of dimensionality reduced models fitted with sets of 2 risk scores and investigate the MSE for several special cases of the covariance matrix. A methodology is proposed to select a best set of P risk scores when P is specified a priori. Simulation studies based on true models of different dimensions(larger than 3) demonstrate that the selected set of P(larger than 1) risk scores outperforms the single …


Estimation In Partially Linear Models With Correlated Observations And Change-Point Models, Liangdong Fan Jan 2018

Estimation In Partially Linear Models With Correlated Observations And Change-Point Models, Liangdong Fan

Theses and Dissertations--Statistics

Methods of estimating parametric and nonparametric components, as well as properties of the corresponding estimators, have been examined in partially linear models by Wahba [1987], Green et al. [1985], Engle et al. [1986], Speckman [1988], Hu et al. [2004], Charnigo et al. [2015] among others. These models are appealing due to their flexibility and wide range of practical applications including the electricity usage study by Engle et al. [1986], gum disease study by Speckman [1988], etc., wherea parametric component explains linear trends and a nonparametric part captures nonlinear relationships.

The compound estimator (Charnigo et al. [2015]) has been used to …


Determinants Of Personal Information Protection Activities In South Korea, Pilku Kang Jan 2018

Determinants Of Personal Information Protection Activities In South Korea, Pilku Kang

MPA/MPP/MPFM Capstone Projects

The purpose of this paper is to investigate how people’s awareness and ways to obtain relevant materials of personal information have influenced individual’s information privacy protection activities. This study uses the data of a 2016 survey on information security published by Korea Information and Security Agency.

The dependent variables of this study are preventive measures for the security of a Personal Computer (PC) and preventive measures against personal information breach. I classify independent variables into four types. They are internet users’ perception about information privacy, such as awareness of the importance of protecting one’s personal information, and awareness of information …


Η' Decay To Π+Π-Π+Π, Ehsan Jafari Jan 2018

Η' Decay To Π+Π-Π+Π−, Ehsan Jafari

Theses and Dissertations--Physics and Astronomy

With the use of chiral theory of mesons [1], [2] we evaluate the decay rate of η′ → π+ππ+π. Our theoretical study of this problem is different from the previous theo- retical study [3] and our predicted result is in a good agreement with the experiment. In this chiral theory we evaluate Feynman diagrams up to one loop and the decay rate is calculated with the use of triangle and box diagrams. The ρ0 meson includes in both type of diagrams as a resonance state. Divergent integrals in the loop calculations …


Stratigraphy And Organic Geochemistry Reveal Patterns Of Late Quaternary Paleo-Productivity At Mono Lake, California, Bailee Nicole Hodelka Jan 2018

Stratigraphy And Organic Geochemistry Reveal Patterns Of Late Quaternary Paleo-Productivity At Mono Lake, California, Bailee Nicole Hodelka

Theses and Dissertations--Earth and Environmental Sciences

Mono Lake (CA) is a hydrologically closed lacustrine basin well-known for its paleo-shorelines, which record fluctuations in water level for the last deglacial and late Holocene. Mono Lake is a sentinel of California’s water supply, situated in the rain shadow of the Sierra Nevada, a mountain range whose snowpack is a vital source of freshwater for urban and agricultural districts to the west and south. Recent droughts, floods, and wildfires show that California is threatened by climate change, but how these changes impact and get recorded by Mono Lake sediments remains poorly known. Here, we use a new radiocarbon-dated deepwater …


Occurrence And Attributes Of Two Echinoderm-Bearing Faunas From The Upper Mississippian (Chesterian; Lower Serpukhovian) Ramey Creek Member, Slade Formation, Eastern Kentucky, U.S.A., Ann Well Harris Jan 2018

Occurrence And Attributes Of Two Echinoderm-Bearing Faunas From The Upper Mississippian (Chesterian; Lower Serpukhovian) Ramey Creek Member, Slade Formation, Eastern Kentucky, U.S.A., Ann Well Harris

Theses and Dissertations--Earth and Environmental Sciences

Well-preserved echinoderm faunas are rare in the fossil record, and when uncovered, understanding their occurrence can be useful in interpreting other faunas. In this study, two such faunas of the same age from separate localities in the shallow-marine Ramey Creek Member of the Slade Formation in the Upper Mississippian (Chesterian) rocks of eastern Kentucky are examined. Of the more than 5,000 fossil specimens from both localities, only 9–34 percent were echinoderms from 3–5 classes. Nine non-echinoderm (8 invertebrate and one vertebrate) classes occurred at both localities, but of these, bryozoans, brachiopods and sponges dominated. To understand the attributes of both …


Electronic And Optical Properties Of Metastable Epitaxial Thin Films Of Layered Iridates, Maryam Souri Jan 2018

Electronic And Optical Properties Of Metastable Epitaxial Thin Films Of Layered Iridates, Maryam Souri

Theses and Dissertations--Physics and Astronomy

The layered iridates such as Sr2IrO4 and Sr3Ir2O7, have attracted substantial attention due to their novel electronic states originating from strong spin-orbit coupling and electron-correlation. Recent studies have revealed the possibilities of novel phases such as topological insulators, Weyl semimetals, and even a potential high-Tc superconducting state with a d-wave gap. However, there are still controversial issues regarding the fundamental electronic structure of these systems: the origin of the insulating gap is disputed as arising either from an antiferromagnetic ordering, i.e. Slater scheme or electron-correlation, i.e. Mott scheme. …