Life Sciences Commons^™

Myofilament Calcium Sensitivity: Consequences Of The Effective Concentration Of Troponin I, Jalal K. Siddiqui, Svetlana B. Tikunova, Shane D. Walton, Bin Liu, Meredith Meyer, Pieter P. De Tombe, Nathan Neilson, Peter M. Kekenes-Huskey, Hussam E. Salhi, Paul M.L. Janssen, Brandon J. Biesiadecki, Jonathan P. Davis

Chemistry Faculty Publications

Control of calcium binding to and dissociation from cardiac troponin C (TnC) is essential to healthy cardiac muscle contraction/relaxation. There are numerous aberrant post-translational modifications and mutations within a plethora of contractile, and even non-contractile, proteins that appear to imbalance this delicate relationship. The direction and extent of the resulting change in calcium sensitivity is thought to drive the heart toward one type of disease or another. There are a number of molecular mechanisms that may be responsible for the altered calcium binding properties of TnC, potentially the most significant being the ability of the regulatory domain of TnC to …

Very Rapid Onset Cannabis Dependence Risk In Relation To Co-Occurring Use Of Other Psychoactive Drugs, Olga A. Vsevolozhskaya, Fernando A. Wagner, James C. Anthony

Biostatistics Presentations

Background: Epidemiological estimates for lifetime cumulative incidence indicate that for every 9-11 who start using cannabis, one becomes a case of the cannabis dependence syndrome (CDS) – i.e., roughly 9%-11%. More recent estimates clarify that CDS risk might be much lower among ’cannabis only’ users, due in part to the fact that many ’cannabis only’ users try the drug a few times and never again. We turned to Hill functional analysis in order to study CDS probability soon after 1st cannabis use, estimated across strata defined by the number of recent days of cannabis use, with an acknowledgment that a …

Adjustment And Optimization Of The Cropping Systems Under Water Constraint, Pingli An, Wei Ren, Xiliin Liu, Mengmei Song, Xuemin Li

Plant and Soil Sciences Faculty Publications

The water constraint on agricultural production receives growing concern with the increasingly sharp contradiction between demand and supply of water resources. How to mitigate and adapt to potential water constraint is one of the key issues for ensuring food security and achieving sustainable agriculture in the context of climate change. It has been suggested that adjustment and optimization of cropping systems could be an effective measure to improve water management and ensure food security. However, a knowledge gap still exists in how to quantify potential water constraint and how to select appropriate cropping systems. Here, we proposed a concept of …

Comparing Performance Of Non-Tree-Based And Tree-Based Association Mapping Methods, Katherine L. Thompson, David W. Fardo

Statistics Faculty Publications

A central goal in the biomedical and biological sciences is to link variation in quantitative traits to locations along the genome (single nucleotide polymorphisms). Sequencing technology has rapidly advanced in recent decades, along with the statistical methodology to analyze genetic data. Two classes of association mapping methods exist: those that account for the evolutionary relatedness among individuals, and those that ignore the evolutionary relationships among individuals. While the former methods more fully use implicit information in the data, the latter methods are more flexible in the types of data they can handle. This study presents a comparison of the 2 …

Causal Effect Estimation In Sequencing Studies: A Bayesian Method To Account For Confounder Adjustment Uncertainty, Chi Wang, Jinpeng Liu, David W. Fardo

Biostatistics Faculty Publications

Estimating the causal effect of a single nucleotide variant (SNV) on clinical phenotypes is of interest in many genetic studies. The effect estimation may be confounded by other SNVs as a result of linkage disequilibrium as well as demographic and clinical characteristics. Because a large number of these other variables, which we call potential confounders, are collected, it is challenging to select and adjust for the variables that truly confound the causal effect. The Bayesian adjustment for confounding (BAC) method has been proposed as a general method to estimate the average causal effect in the presence of a large number …

Fedrr: Fast, Exhaustive Detection Of Redundant Hierarchical Relations For Quality Improvement Of Large Biomedical Ontologies, Guangming Xing, Guo-Qiang Zhang, Licong Cui

Institute for Biomedical Informatics Faculty Publications

Background: Redundant hierarchical relations refer to such patterns as two paths from one concept to another, one with length one (direct) and the other with length greater than one (indirect). Each redundant relation represents a possibly unintended defect that needs to be corrected in the ontology quality assurance process. Detecting and eliminating redundant relations would help improve the results of all methods relying on the relevant ontological systems as knowledge source, such as the computation of semantic distance between concepts and for ontology matching and alignment.

Results: This paper introduces a novel and scalable approach, called FEDRR – Fast, Exhaustive …

Weighted-Samgsr: Combining Significance Analysis Of Microarray-Gene Set Reduction Algorithm With Pathway Topology-Based Weights To Select Relevant Genes, Suyan Tian, Howard H. Chang, Chi Wang

Biostatistics Faculty Publications

Background: It has been demonstrated that a pathway-based feature selection method that incorporates biological information within pathways during the process of feature selection usually outperforms a gene-based feature selection algorithm in terms of predictive accuracy and stability. Significance analysis of microarray-gene set reduction algorithm (SAMGSR), an extension to a gene set analysis method with further reduction of the selected pathways to their respective core subsets, can be regarded as a pathway-based feature selection method.

Methods: In SAMGSR, whether a gene is selected is mainly determined by its expression difference between the phenotypes, and partially by the number of pathways to …

Comparative Transcriptomic Analysis Of Two Brassica Napus Near-Isogenic Lines Reveals A Network Of Genes That Influences Seed Oil Accumulation, Jingxue Wang, Sanjay Kumar Singh, Chunfang Du, Chen Li, Jianchun Fan, Sitakanta Pattanaik, Ling Yuan

Plant and Soil Sciences Faculty Publications

Rapeseed (Brassica napus) is an important oil seed crop, providing more than 13% of the world’s supply of edible oils. An in-depth knowledge of the gene network involved in biosynthesis and accumulation of seed oil is critical for the improvement of B. napus. Using available genomic and transcriptomic resources, we identified 1,750 acyl-lipid metabolism (ALM) genes that are distributed over 19 chromosomes in the B. napus genome. B. rapa and B. oleracea, two diploid progenitors of B. napus, contributed almost equally to the ALM genes. Genome collinearity analysis demonstrated that the majority of the …

Identification Of Control Targets In Boolean Molecular Network Models Via Computational Algebra, David Murrugarra, Alan Veliz-Cuba, Boris Aguilar, Reinhard Laubenbacher

Mathematics Faculty Publications

Background: Many problems in biomedicine and other areas of the life sciences can be characterized as control problems, with the goal of finding strategies to change a disease or otherwise undesirable state of a biological system into another, more desirable, state through an intervention, such as a drug or other therapeutic treatment. The identification of such strategies is typically based on a mathematical model of the process to be altered through targeted control inputs. This paper focuses on processes at the molecular level that determine the state of an individual cell, involving signaling or gene regulation. The mathematical model type …

Vasoactivity And Vasoconstriction Changes In Cattle Related To Time Off Toxic Endophyte-Infected Tall Fescue, James L. Klotz, Glen E. Aiken, Jessica R. Bussard, Andrew P. Foote, David L. Harmon, Ben M. Goff, F. Neal Schrick, James R. Strickland

Plant and Soil Sciences Faculty Publications

Previous research has indicated that serotonergic and α-adrenergic receptors in peripheral vasculature are affected by exposure of cattle grazing toxic endophyte-infected (E+; Epichlöe coenophialia) tall fescue (Lolium arundinaceum). The objective of this experiment was to determine the period of time necessary for the vascular effects of ergot alkaloids to subside. Two experiments were conducted to investigate changes in vascular contractile response and vasoconstriction over time relative to removal from an ergot alkaloid-containing E+ tall fescue pasture. In Experiment 1, lateral saphenous vein biopsies were conducted on 21 predominantly Angus steers (357 ± 3 kg body weight) at …

Influence Of Source Credibility On Consumer Acceptance Of Genetically Modified Foods In China, Mingyang Zhang, Chao Chen, Wuyang Hu, Lijun Chen, Jintao Zhan

Agricultural Economics Faculty Publications

This paper examines the reasoning mechanism behind the consumer acceptance of genetically modified foods (GMFs) in China, and investigates influence of source credibility on consumer acceptance of GMFs. Based on the original Persuasion Model—which was developed by Carl Hovland, an American psychologist and pioneer in the study of communication and its effect on attitudes and beliefs—we conducted a survey using multistage sampling from 1167 urban residents, which were proportionally selected from six cities in three economic regions (south, central, and north) in the Jiangsu province through face to face interviews. Mixed-process regression that could correct endogeneity and ordered probit model …

Methane Emissions From Global Rice Fields: Magnitude, Spatiotemporal Patterns, And Environmental Controls, Bowen Zhang, Hanqin Tian, Wei Ren, Bo Tao, Chaoqun Lu, Jia Yang, Kamaljit Banger, Shufen Pan

Plant and Soil Sciences Faculty Publications

Given the importance of the potential positive feedback between methane (CH₄) emissions and climate change, it is critical to accurately estimate the magnitude and spatiotemporal patterns of CH₄ emissions from global rice fields and better understand the underlying determinants governing the emissions. Here we used a coupled biogeochemical model in combination with satellite-derived contemporary inundation area to quantify the magnitude and spatiotemporal variation of CH₄ emissions from global rice fields and attribute the environmental controls of CH₄ emissions during 1901–2010. Our study estimated that CH₄ emissions from global rice fields varied from 18.3 ± …

Modeling PCo2 Variability In The Gulf Of Mexico, Zuo Xue, Ruoying He, Katja Fennel, Wei-Jun Cai, Steven Lohrenz, Wei-Jen Huang, Hanqin Tian, Wei Ren, Zhengchen Zang

Plant and Soil Sciences Faculty Publications

A three-dimensional coupled physical–biogeochemical model was used to simulate and examine temporal and spatial variability of sea surface pCO₂ in the Gulf of Mexico (GoM). The model was driven by realistic atmospheric forcing, open boundary conditions from a data-assimilative global ocean circulation model, and observed freshwater and terrestrial nutrient and carbon input from major rivers. A 7-year model hindcast (2004–2010) was performed and validated against ship measurements. Model results revealed clear seasonality in surface pCO₂ and were used to estimate carbon budgets in the Gulf. Based on the average of model simulations, the GoM was a …

Regulation Of Pyrroloquinoline Quinone-Dependent Glucose Dehydrogenase Activity In The Model Rhizosphere-Dwelling Bacterium Pseudomonas Putida Kt2440, Ran An, Luke Moe

Plant and Soil Sciences Faculty Publications

Soil-dwelling microbes solubilize mineral phosphates by secreting gluconic acid, which is produced from glucose by a periplasmic glucose dehydrogenase (GDH) that requires pyrroloquinoline quinone (PQQ) as a redox coenzyme. While GDH-dependent phosphate solubilization has been observed in numerous bacteria, little is known concerning the mechanism by which this process is regulated. Here we use the model rhizosphere-dwelling bacterium Pseudomonas putida KT2440 to explore GDH activity and PQQ synthesis, as well as gene expression of the GDH-encoding gene (gcd) and PQQ biosynthesis genes (pqq operon) while under different growth conditions. We also use reverse transcription-PCR to identify transcripts …

A R2r3-Myb Transcription Factor Regulates The Flavonol Biosynthetic Pathway In A Traditional Chinese Medicinal Plant, Epimedium Sagittatum, Wenjun Huang, A. B. M. Khaldun, Jianjun Chen, Chanjuan Zhang, Haiyan Lv, Ling Yuan, Ying Wang

Plant and Soil Sciences Faculty Publications

Flavonols as plant secondary metabolites with vital roles in plant development and defense against UV light, have been demonstrated to be the main bioactive components (BCs) in the genus Epimedium plants, several species of which are used as materials for Herba Epimedii, an important traditional Chinese medicine. The flavonol biosynthetic pathway genes had been already isolated from Epimedium sagittatum, but a R2R3-MYB transcription factor regulating the flavonol synthesis has not been functionally characterized so far in Epimedium plants. In this study, we isolated and characterized the R2R3-MYB transcription factor EsMYBF1 involved in regulation of the flavonol biosynthetic pathway …

High-Input Management Systems Effect On Soybean Seed Yield, Yield Components, And Economic Break-Even Probabilities, John M. Orlowski, Bryson J. Haverkamp, Randall G. Laurenz, David A. Marburger, Eric W. Wilson, Shaun N. Casteel, Shawn P. Conley, Seth L. Naeve, Emerson D. Nafziger, Kraig L. Roozeboom, William J. Ross, Kurt D. Thelen, Chad Lee

Plant and Soil Sciences Faculty Publications

Elevated soybean [Glycine max (L.) Merr.] prices have spurred interest in maximizing soybean seed yield and has led growers to increase the number of inputs in their production systems. However, little information exists about the effects of high-input management on soybean yield and profitability. The purpose of this study was to investigate the effects of individual inputs, as well as combinations of inputs marketed to protect or increase soybean seed yield, yield components, and economic break-even probabilities. Studies were established in nine states and three soybean growing regions (North, Central, and South) between 2012 and 2014. In each site-year …

Mutation Linked To Autosomal Dominant Nocturnal Frontal Lobe Epilepsy Reduces Low-Sensitivity Α4Β2, And Increases Α5Α4Β2, Nicotinic Receptor Surface Expression, Weston A. Nichols, Brandon J. Henderson, Christopher B. Marotta, Caroline Y. Yu, Chris Richards, Dennis A. Dougherty, Henry A. Lester, Bruce N. Cohen

Chemistry Faculty Publications

A number of mutations in α4β2-containing (α4β2*) nicotinic acetylcholine (ACh) receptors (nAChRs) are linked to autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE), including one in the β2 subunit called β2V287L. Two α4β2* subtypes with different subunit stoichiometries and ACh sensitivities co-exist in the brain, a high-sensitivity subtype with (α4)₂(β2)₃ subunit stoichiometry and a low-sensitivity subtype with (α4)₃(β2)₂ stoichiometry. The α5 nicotinic subunit also co-assembles with α4β2 to form a high-sensitivity α5α4β2 nAChR. Previous studies suggest that the β2V287L mutation suppresses low-sensitivity α4β2* nAChR expression in a knock-in mouse model and also that α5 co-expression …

Assessment Of Streamside Management Zones For Conserving Benthic Macroinvertebrate Communities Following Timber Harvest In Eastern Kentucky Headwater Catchments, Joshua K. Adkins, Christopher D. Barton, Scott Grubbs, Jeffrey W. Stringer, Randall K. Kolka

Forestry and Natural Resources Faculty Publications

Headwater streams generally comprise the majority of stream area in a watershed and can have a strong influence on downstream food webs. Our objective was to determine the effect of altering streamside management zone (SMZ) configurations on headwater aquatic insect communities. Timber harvests were implemented within six watersheds in eastern Kentucky. The SMZ configurations varied in width, canopy retention and best management practice (BMP) utilization at the watershed scale. Benthic macroinvertebrate samples collected one year before and four years after harvest indicated few differences among treatments, although post-treatment abundance was elevated in some of the treatment streams relative to the …

Performance Of Endophyte Infected Tall Fescue In Europe And North America, Kari Saikkonen, Timothy D. Phillips, Stanley H. Faeth, Rebecca L. Mcculley, Irma Saloniemi, Marjo Helander

Plant and Soil Sciences Faculty Publications

Human assisted plant invasions from Europe to North America have been more common than the reverse. We tested endophyte-mediated performance of tall fescue in parallel three year experiments in Europe and the USA using endophyte infected and uninfected wild and cultivated plants. Experimental plants were subjected to nutrient and water treatments. Whereas endophyte infection increased tall fescue performance in general, the effects of endophytes on plant growth and reproduction varied among plant origins under different environmental conditions. Naturally endophyte-free Finnish cultivar ‘Retu’ performed equally well as ‘Kentucky-31’ in both geographic locations. All Eurasian origin plants performed well in the US. …

Are Consumers Willing To Pay More For Sustainable Products? A Study Of Eco-Labeled Tuna Steak, Guzhen Zhou, Wuyang Hu, Wenchao Huang

Agricultural Economics Faculty Publications

A high demand for seafood leads to overfishing, harms the long-term health of seafood stocks, and threatens environmental sustainability in oceans. Sustainability certification is one of the major sustainability movements and is known as eco-labeling. For instance, in the tuna industry, leading tuna brands have committed to protecting sea turtles by allowing the tracing of the source of their tuna “from catch to can.” This paper relies on an Internet survey on consumers from Kentucky conducted in July 2010. The survey investigates household-level tuna steak (sashimi grade) consumption and examines consumer preferences for eco-labeling (“Certified Turtle Safe” (CTS) in this …

Quantitative Evidence For The Effects Of Multiple Drivers On Continental-Scale Amphibian Declines, Evan H. Campbell Grant, David A. W. Miller, Benedikt R. Schmidt, Michael J. Adams, Staci M. Amburgey, Thierry Chambert, Sam S. Cruickshank, Robert N. Fisher, David M. Green, Blake R. Hossack, Pieter T. J. Johnson, Maxwell B. Joseph, Tracy A. G. Rittenhouse, Maureen E. Ryan, J. Hardin Waddle, Susan C. Walls, Larissa L. Bailey, Gary M. Fellers, Thomas A. Gorman, Andrew M. Ray, David S. Pilliod, Steven J. Price, Daniel Saenz, Walt Sadinski, Erin Muths

Forestry and Natural Resources Faculty Publications

Since amphibian declines were first proposed as a global phenomenon over a quarter century ago, the conservation community has made little progress in halting or reversing these trends. The early search for a “smoking gun” was replaced with the expectation that declines are caused by multiple drivers. While field observations and experiments have identified factors leading to increased local extinction risk, evidence for effects of these drivers is lacking at large spatial scales. Here, we use observations of 389 time-series of 83 species and complexes from 61 study areas across North America to test the effects of 4 of the …

Genetic Engineering And Sustainable Crop Disease Management: Opportunities For Case-By-Case Decision-Making, Paul Vincelli

Plant Pathology Faculty Publications

Genetic engineering (GE) offers an expanding array of strategies for enhancing disease resistance of crop plants in sustainable ways, including the potential for reduced pesticide usage. Certain GE applications involve transgenesis, in some cases creating a metabolic pathway novel to the GE crop. In other cases, only cisgenessis is employed. In yet other cases, engineered genetic changes can be so minimal as to be indistinguishable from natural mutations. Thus, GE crops vary substantially and should be evaluated for risks, benefits, and social considerations on a case-by-case basis. Deployment of GE traits should be with an eye towards long-term sustainability; several …

Mapping Temperate Vegetation Climate Adaptation Variability Using Normalized Land Surface Phenology, Liang Liang, Mark D. Schwartz, Xiaoyang Zhang

Geography Faculty Publications

Climate influences geographic differences of vegetation phenology through both contemporary and historical variability. The latter effect is embodied in vegetation heterogeneity underlain by spatially varied genotype and species compositions tied to climatic adaptation. Such long-term climatic effects are difficult to map and therefore often neglected in evaluating spatially explicit phenological responses to climate change. In this study we demonstrate a way to indirectly infer the portion of land surface phenology variation that is potentially contributed by underlying genotypic differences across space. The method undertaken normalized remotely sensed vegetation start-of-season (or greenup onset) with a cloned plants-based phenological model. As the …

Photocatalytic Reduction Of Fumarate To Succinate On Zns Mineral Surfaces, Ruixin Zhou, Marcelo I. Guzman

Chemistry Faculty Publications

The reductive tricarboxylic acid (rTCA) cycle is an important central biosynthetic pathway that fixes CO₂ into carboxylic acids. Among the five reductive steps in the rTCA cycle, the two-electron reduction of fumarate to succinate proceeds nonenzymatically on the surface of photoexcited sphalerite (ZnS) colloids suspended in water. This model reaction is chosen to systematically study the surface photoprocess occurring on ZnS in the presence of [Na₂S] (1–10 mM) hole scavenger at 15 °C. Experiments at variable pH (5–10) indicate that monodissociated fumaric acid is the primary electron acceptor forming the monoprotic form of succinic acid. The following …

Poster Session, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

1. Fecal Coliforms and E. coli Levels in Surface Waters from McConnell Springs, 2011-2015, David Price, Division of Water Quality, Lexington-Fayette County Government
2. Buried Soils as an Important Control on C Storage along Human-Impacted Floodplains in Kentucky, USA, Ashley Casselberry and Gary Stinchcomb, Dept. of Geosciences & Watershed Studies Institute, Murray State University
3. Buried Soils are an Important Chemical Interface Controlling Mineral Weathering and Solute Gradients along River Corridors, Gary Stinchcomb, Ashley Casselberry, and Abigail Smith, Dept. of Geosciences & Watershed Studies Institute, Murray State University
4. Geospatial Evaluation of Sewer Gas to Indoor Air Pathways Relevant for Vapor …

Track 2: Stream Restoration, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Bankfull Open Channel Flow Model: Development and Applications for Stream Restoration Design, Charles Davis and Brian Belcher, Beaver Creek Hydrology, LLC, Lexington, KY
• Using Stream Restoration for Pollution Reduction, Wanda Lawson, Stantec Consulting Services, Inc, Louisville, KY
• KDFWR Hatchery Creek Stream and Wetlands Restoration Project - A Unique Opportunity to Maximize Trout Habitat, Create Recreational Opportunities and Provide Mitigation Credits: Planning & Design, Oakes Routt and others, Stantec Consulting Services, Inc., Louisville, KY
• KDFWR Hatchery Creek Stream and Wetlands Restoration Project - A Unique Opportunity to Maximize Trout Habitat, Create Recreational Opportunities and Provide Mitigation Credits: Construction …

Track 2: Environmental Impact, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Toward Rapid Detection of Phytophthora cinnamomi in Appalachian Streams, Kenton Sena and others, Dept. of Forestry, University of Kentucky
• Arsenic in Water and Risk of Cancer in Humans, Steven Lamm and others, Center for Epidemiology and Global Health, Washington, DC
• Examining the Impacts of Valley Fills in Stream Ecosystems on Amphibian and Aquatic Insect Communities in Southeastern Kentucky, John Bourne and Stephen Richter, Patuxent Research Refuge, Laurel, MD and Eastern Kentucky University
• The Wetlands Prioritization Tool, Caroline Chan, Kentucky Division of Water, Frankfort, KY

Track 2: Soils, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Controlled Drainage in Western Kentucky: Mitigating Water Stress and Reducing Nutrient Loss to Surface Waters in Grain Crop Production, Ethan Snyder and Carrie Knott, Dept. of Plant and Soil Sciences, University of Kentucky
• Comparing Simulated Soil Properties to Field Derived Values in Forested and Grassland Catena of MLRA 120, Trinity Baker and others, Dept. of Plant and Soil Sciences, University of Kentucky
• Soil Infiltration Rates in Six Agricultural Fields of Western Kentucky, Landon Gibbs and Iin Handayani, Dept. of Agricultural Science, Murray State University
• Investigation of the Climate Modeling Factors Impacting Forecasted Streamflow for Central Kentucky, …

Track 1: Source Water Protection, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Kentucky's Source Water Protection Assistance Program, Robert Blair and James Calhoun, Watershed Management Branch, Kentucky Division of Water and Jessica Moore, U.S. EPA, Dallas Texas
• Source Water Protection Assistance Program, Trimble County Water District #1 Customer Outreach Program, Andrew Stark, Trimble County Water District #1, Bedford, KY
• Kentucky Rural Water Association and Water Utilities' Efforts in Protecting Drinking Water Sources, Jack Stickney, Kentucky Rural Water Association, Bowling Green, KY
• Source Water Protection for the Riverbank Filtration System, Kay Ball and Rob Newman, Louisville Water Company, Louisville, KY

Track 1: Karst, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Characteristics of Cover-Collapse Sinkholes in Kentucky, James C. Currens, Kentucky Geological Survey
• Data and Model Investigation of a Fluviokarst System in the Bluegrass Region: Water, Sediment, and Carbon Interactions, Admin Husic and others, Dept. of Civil Engineering, University of Kentucky
• Sourcing and Dynamics of Karst Hydrologic Inputs on Harmful Algal Bloom Occurrences in Kentucky Lakes, Robert Schaefer and Jason Polk, Dept. of Geography and Geology, Western Kentucky University
• Investigation of Fecal Contamination in the Little River Basin, Kentucky Using Microbial Source Tracking and Fecal Indicator Bacteria, 2013-2014, Mac A. Cherry, USGS, Kentucky Water Science Center