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2016

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Repeat Exposure To Leg Swing Perturbations During Treadmill Training Induces Long-Term Retention Of Increased Step Length In Human Sci: A Pilot Randomized Controlled Study, Ming Wu, Jill M. Landry, Janis Kim, Brian D. Schmit, Sheng-Che Yen, Jillian Mcdonald, Yunhui Zhang Dec 2016

Repeat Exposure To Leg Swing Perturbations During Treadmill Training Induces Long-Term Retention Of Increased Step Length In Human Sci: A Pilot Randomized Controlled Study, Ming Wu, Jill M. Landry, Janis Kim, Brian D. Schmit, Sheng-Che Yen, Jillian Mcdonald, Yunhui Zhang

Biomedical Engineering Faculty Research and Publications

Objective: To determine whether repeat exposure to force perturbations during treadmill training can induce long-term retention of improved step length and overall improvements in locomotor function in persons with spinal cord injury.

Design: Fourteen patients with spinal cord injury were recruited and randomly assigned to swing resistance or swing assistance training groups. A controlled swing resistance or assistance force, for resistance or assistance training groups, respectively, was applied to both legs through a cable-driven robotic system during treadmill training. Each participant trained 3 times per week for 6 weeks. Step length, walking speed, 6-minute walking distance, and other clinical assessments …


Enhancements In Localized Classification For Uterine Cervical Cancer Digital Histology Image Assessment, Peng Guo, Haidar A. Almubarak, Koyel Banerjee, R. Joe Stanley, L. Rodney Long, Sameer K. Antani, George R. Thoma, Rosemary E. Zuna, Shelliane R. Frazier, Randy Hays Moss, William V. Stoecker Dec 2016

Enhancements In Localized Classification For Uterine Cervical Cancer Digital Histology Image Assessment, Peng Guo, Haidar A. Almubarak, Koyel Banerjee, R. Joe Stanley, L. Rodney Long, Sameer K. Antani, George R. Thoma, Rosemary E. Zuna, Shelliane R. Frazier, Randy Hays Moss, William V. Stoecker

Electrical and Computer Engineering Faculty Research & Creative Works

Background: In previous research, we introduced an automated, localized, fusion-based approach for classifying uterine cervix squamous epithelium into Normal, CIN1, CIN2, and CIN3 grades of cervical intraepithelial neoplasia (CIN) based on digitized histology image analysis. As part of the CIN assessment process, acellular and atypical cell concentration features were computed from vertical segment partitions of the epithelium region to quantize the relative distribution of nuclei.

Methods: Feature data was extracted from 610 individual segments from 61 images for epithelium classification into categories of Normal, CIN1, CIN2, and CIN3. The classification results were compared against CIN labels obtained from two pathologists …


Increasing Superintendent Longevity In Kansas, Cory Lee Gibson Dec 2016

Increasing Superintendent Longevity In Kansas, Cory Lee Gibson

Graduate Theses and Dissertations

This study aims to illuminate the factors that may impact a superintendent’s longevity in the same district. Specifically, this study is motivated by four research questions: (1) What factors do superintendents in Kansas attribute to remaining in the same position greater than six years? (2) What factors do superintendents in Kansas attribute as the causes for leaving a district? (3) What is the current level of satisfaction of Kansas school superintendents within their current roles? and (4) What are some changes in policy or practice that may increase superintendent longevity in Kansas?

According to Dale Dennis, Kansas Deputy Commissioner of …


A Bifunctional Nanocomposites Based Electrochemical Biosensor For In-Field Detection Of Pathogenic Bacteria In Food, Meng Xu Dec 2016

A Bifunctional Nanocomposites Based Electrochemical Biosensor For In-Field Detection Of Pathogenic Bacteria In Food, Meng Xu

Graduate Theses and Dissertations

This research focused on the application of electrochemical biosensors for the rapid detection of pathogenic bacteria, Escherichia coli O157:H7 and Salmonella Typhimurium, in foods. The possible presence of pathogenic bacteria in foods has always been a great threat to the wellbeing of people and the revenue of food companies. Therefore, the demand for rapid and sensitive methods to detect foodborne pathogens is growing. In this research, an impedimetric immunosensor was first developed for the rapid detection of E. coli O157:H7 and S. Typhimurium in foods. It was based on the techniques of immunomagnetic separation, enzyme labelling, and electrochemical impedance spectroscopy …


Fleeing To Fault Zones: Incorporating Syrian Refugees Into Earthquake Risk Analysis Along The East Anatolian And Dead Sea Rift Fault Zones, Bradley Wilson Dec 2016

Fleeing To Fault Zones: Incorporating Syrian Refugees Into Earthquake Risk Analysis Along The East Anatolian And Dead Sea Rift Fault Zones, Bradley Wilson

Graduate Theses and Dissertations

The influx of millions of Syrian refugees into Turkey has rapidly changed the population distribution along the Dead Sea Rift and East Anatolian Fault zones. In contrast to other countries in the Middle East where refugees are accommodated in camp environments, the majority of displaced individuals in Turkey are integrated into local cities, towns, and villages—placing stress on urban settings and increasing potential exposure to strong earthquake shaking. Yet, displaced populations are not traditionally captured in data sources used in earthquake risk analysis or loss estimations. Accordingly, this study presents a district-level analysis assessing the spatial overlap of earthquake hazards …


Preparedness To Counsel Transgender College Students: Perceptions Of College Mental Health Clinicians, Valerie G. Couture Dec 2016

Preparedness To Counsel Transgender College Students: Perceptions Of College Mental Health Clinicians, Valerie G. Couture

Graduate Theses and Dissertations

The purpose of this study was to assess the perceived preparedness levels of college mental health clinicians to counsel transgender college students. Multicultural counseling competency is required of professional counselors and transgender individuals are considered to be part of the multicultural population. A survey was completed by college mental health counselors (N = 84) from across the United States. The results showed a moderate amount of preparedness overall with no significant differences based on years of counseling experience nor graduation from a CACREP accredited program. Results did show the participants believed they do have a professional duty to be knowledgeable …


The Lived Experiences Of Emergency Department Personnel In Working With Individuals With Mental Health Needs, Sarah Wohlford-Neubauer Dec 2016

The Lived Experiences Of Emergency Department Personnel In Working With Individuals With Mental Health Needs, Sarah Wohlford-Neubauer

Graduate Theses and Dissertations

Individuals who work in emergency departments and emergency services in the United States have daunting, overwhelming, and difficult tasks to perform. In addition to medical emergencies that include physical trauma and illnesses, emergency personnel treat individuals with psychiatric emergencies. This qualitative research study explored the lived experiences of ten emergency department personnel that had experienced working with individuals with mental health needs. The ultimate purpose of the study was to break down individuals’ experiences into a shared description of a universal phenomenon. The study utilized a phenomenological, qualitative research design to capture the essence of this phenomenon. Participants’ responses to …


Examining The Sociocultural Experiences Of Cherokee Nation Citizens In Athletic Competition And Sport, Michael Dewayne Merrie Dec 2016

Examining The Sociocultural Experiences Of Cherokee Nation Citizens In Athletic Competition And Sport, Michael Dewayne Merrie

Graduate Theses and Dissertations

The purpose of this dissertation was to examine the sociocultural experiences of Cherokee adults in athletic competition and sport. Specifically, following a qualitative design, fifteen participants were interviewed about their personal experiences in athletic competition and sport while growing up in rural Oklahoma. Interviews were open-ended and followed a semi-structured script of questions with additional probes. Once completed, the recorded interviews were transcribed and data were analyzed. The data revealed six axial codes and three selective codes. Cherokee culture, psychoSocial identity, and athletic competition were the three major selective codes discovered in this study. Qualitative analyses revealed that participants have …


Genetic Determinants Of Salmonella And Campylobacter Required For In Vitro Fitness, Rabindra Kumar Mandal Dec 2016

Genetic Determinants Of Salmonella And Campylobacter Required For In Vitro Fitness, Rabindra Kumar Mandal

Graduate Theses and Dissertations

Non-typhoidal Salmonella (NTS) and Campylobacter play a major role in foodborne illness caused by the consumption of food contaminated by pathogens worldwide. A comprehensive understanding of the genetic factors that increase the survival fitness of these foodborne pathogens will effectively help us formulate mitigation strategies without affecting the nutrition ecology. The objective of this study was to identify the genetic determinants of Salmonella and Campylobacter that are required for fitness under various in vitro conditions. For the purpose, we used a high throughput Transposon sequencing (Tn-seq) that utilizes next generation sequencing (NGS) to screen hundreds of thousands of mutants simultaneously. …


A Content Analysis Of Advertising On Children’S Television Networks, Demarius Davis Dec 2016

A Content Analysis Of Advertising On Children’S Television Networks, Demarius Davis

Graduate Theses and Dissertations

This content analysis study on licensed characters in advertising collected data in summer 2015 from three children’s cable networks: Cartoon Network, Disney Channel and Nickelodeon. Using Social cognitive theory and based on past research (Barcus, 1975; Atkin, 1976; Calcott & Lee, 1994; Stitt & Kunkel, 2008; LoDolce et al., 2013; Castonguay et al., 2013), the study examined whether the use of licensed characters and emotional appeals varied in advertising for healthy or unhealthy foods, mass media genre and the character’s gender. The study found licensed characters are more likely to be used to promote unhealthy foods, originate from movies and …


Examining Exemplary P-20 Partnerships Using A Mixed Methods Approach, Elizabeth Erin Smith Dec 2016

Examining Exemplary P-20 Partnerships Using A Mixed Methods Approach, Elizabeth Erin Smith

Graduate Theses and Dissertations

Historically, P-12 schools and institutions of higher education have operated independently of each other, creating a gap that acts as a barrier between high school and postsecondary institutions. This gap is blamed for many societal issues including high college remediation rates, low college-going rates among minority groups, and low six-year college graduation rates. P-20 partnerships, agreements between P-12 schools and institutions of higher education with the purpose of improving the P-20 education system, have emerged as a way to address these problems.

From laboratory schools in the 19th century to modern-day professional development schools, P-20 partnerships in teacher education have …


The Effects Of Using Cinnamon Leaf And Bark Essential Oils On Listeria Monocytogenes (L.M.), Salmonella Typhimurium (S.T.), In Model System, Strawberry Shake And Fresh Celery, And Sensory & Shelf Life Studies, Wafaa Brnawi Dec 2016

The Effects Of Using Cinnamon Leaf And Bark Essential Oils On Listeria Monocytogenes (L.M.), Salmonella Typhimurium (S.T.), In Model System, Strawberry Shake And Fresh Celery, And Sensory & Shelf Life Studies, Wafaa Brnawi

Graduate Theses and Dissertations

Essential oils derived from the bark and leaves of the cinnamon plant have long been used as natural preservatives and flavoring agents in different types of foods. In this study, we evaluated the antimicrobial effects of cinnamon essential oils (CEOs), obtained from cinnamon leaf or bark, against two foodborne pathogens i.e., Salmonella Typhimurium (S.T.) and Listeria monocytogenes (L.m.). Two different concentrations of microbial loading were used i.e.,109 and 104, cultured in nutrient media broth, strawberry shakes, and on celery sticks. Both CEOs of leaf and bark at 0.5% and 1% were found to completely inhibit S.T. and L.m., immediately after …


The Association Between Known Risk Factors For Type 2 Diabetes, And The Body Mass Index Of Diabetic Adults, Faten Ahmed Almubarak Dec 2016

The Association Between Known Risk Factors For Type 2 Diabetes, And The Body Mass Index Of Diabetic Adults, Faten Ahmed Almubarak

Graduate Theses and Dissertations

Diabetes mellitus (DM) has been a major research topic in scientific health studies. Diabetes is a chronic condition in which blood glucose levels are chronically elevated to more than 7.0 mmol/l in fasting plasma glucose test. The most common form of diabetes is Type 2 (TD2M). The International Diabetes Federation (2015) estimated the number of DM cases worldwide to be 415 million people in 2015. This number is predicted to increase by the year 2040, to 642 million people. The purpose of this study was to use the National Health Interview Survey (NHIS) data to identify the risk factors for …


Two Essays On Analytical Capabilities: Antecedents And Consequences, Rishikesh Jena Dec 2016

Two Essays On Analytical Capabilities: Antecedents And Consequences, Rishikesh Jena

Graduate Theses and Dissertations

Although organizations are rapidly embracing business analytics (BA) to enhance organizational performance, only a small proportion have managed to build analytical capabilities. While BA continues to draw attention from academics and practitioners, theoretical understanding of antecedents and consequences of analytical capabilities remain limited and lack a systematic view. In order to address the research gap, the two essays investigate: (a) the impact of organization’s core information processing mechanisms and its impact on analytical capabilities, (b) the sequential approach to integration of IT-enabled business processes and its impact on analytical capabilities, and (c) network position and its impact on analytical capabilities. …


Attachment Styles And Trust Propensity In Females With Borderline Personality Disorder, Jacob Matthew White Dec 2016

Attachment Styles And Trust Propensity In Females With Borderline Personality Disorder, Jacob Matthew White

Graduate Theses and Dissertations

Borderline Personality Disorder (BPD) is one of the most frequently encountered and complex disorders in mental health care. Interpersonal impairment is a central issue for individuals with BPD. This complex disorder has received negative stigma along with historically more females than males receiving this diagnosis (Linehan, 1993). Therefore, this study examined a clinical sample of 30 females diagnosed with BPD. Through the collection of data this study used the following measures: a basic demographic questionnaire gathering specific age, ethnicity, current relationship status, parental relationship status, the Experiences in Close Relationships Scale (ECR; Brennan, Clark & Shaver, 1998), and the Propensity …


A Portable And Automatic Biosensing Instrument For Detection Of Foodborne Pathogenic Bacteria In Food Samples, Zhuo Zhao Dec 2016

A Portable And Automatic Biosensing Instrument For Detection Of Foodborne Pathogenic Bacteria In Food Samples, Zhuo Zhao

Graduate Theses and Dissertations

Foodborne diseases are a growing public health problem. In recent years, many rapid detection methods have been reported, but most of them are still in lab research and not practical for use in the field. In this study, a portable and automatic biosensing instrument was designed and constructed for separation and detection of target pathogens in food samples using nanobead-based magnetic separation and quantum dots (QDs)-labeled fluorescence measurement. The instrument consisted of a laptop with LabVIEW software, a data acquisition card (DAQ), a fluorescent detector, micro-pumps, stepper motors, and 3D printed tube holders. First, a sample in a syringe was …


Investigation Of The Optical Properties Of Pbse/Pbx Nanocrystals For Photodetector Applications, Haley Ann Morris Dec 2016

Investigation Of The Optical Properties Of Pbse/Pbx Nanocrystals For Photodetector Applications, Haley Ann Morris

Graduate Theses and Dissertations

Lead selenide and lead selenide/lead sulfide core/shell nanocrystals were investigated for use in near infrared photodetectors. A colloidal synthesis method was used for both the core and core/shell configurations. The lead sulfide shell was examined in order to mitigate oxidation of the nanoparticle surface. Absorbance and photoluminescence spectra were measured at room temperature and 77 K, respectively. Transmission electron microscopy images were also obtained to confirm crystallography and size. Bulk lead selenide was simulated in WIEN2k utilizing the linear-augmented plane wave method of solving density functional theory to better understand the electronic structure of PbSe. The crystal structure, electron density, …


Effect Of Delayed Wrapping And Wrapping Source On Intake And Digestibility Of Alfalfa Silage In Gestating Sheep, Valens Niyigena Dec 2016

Effect Of Delayed Wrapping And Wrapping Source On Intake And Digestibility Of Alfalfa Silage In Gestating Sheep, Valens Niyigena

Graduate Theses and Dissertations

Baling silage with oxygen can result in dry matter deterioration and reduce silage intake by animals. This study was conducted to investigate the effects of two different wrapping sources and time intervals between baling and wrapping on intake and digestibility of alfalfa silage. The second objective was to assess the correlation of alfalfa silage fermentation parameters with intake and digestibility parameters in gestating sheep. Alfalfa silage was baled in large round bales then wrapped with plastic either with (KURA) or without (SUN) an oxygen-limiting barrier either the day of baling or 1, 2 or 3 d after baling. Beginning in …


Phenotypic Analysis And Localization Of Leukocytes At The Site Of Intradermal Injection Of Phytohemagglutinin In Chickens, Kallie Alyce Sullivan Dec 2016

Phenotypic Analysis And Localization Of Leukocytes At The Site Of Intradermal Injection Of Phytohemagglutinin In Chickens, Kallie Alyce Sullivan

Graduate Theses and Dissertations

Phytohemagglutinin (PHA) is commonly used to gain insight into an individual’s cellular immuno-competence. PHA is typically injected intradermally (i.d.) into the skin (e.g. wing web) and the tissue swelling response is then monitored, whereby the extent of the swelling positively relates to the individual’s cellular immune system capabilities. Although i.d. injected PHA was shown to stimulate mononuclear cell- and basophil-infiltration to the site of injection, reports on temporal, qualitative and quantitative aspects of the local PHA response are limited. The objective of this study was to use the growing feather (GF) as a cutaneous test-site to assess and monitor the …


Extracellular Matrix Remodeling And The Inflammatory Response During Skeletal Muscle Regeneration In Sarcopenic Obese Mice, Lemuel Arthur Brown Dec 2016

Extracellular Matrix Remodeling And The Inflammatory Response During Skeletal Muscle Regeneration In Sarcopenic Obese Mice, Lemuel Arthur Brown

Graduate Theses and Dissertations

AIM: Sarocpenic obesity is a national concern within the United States because this metabolic syndrome is tied with reduced mobility and quality of life. Both obesity and aging are associated with insulin-resistance, chronic low-grade inflammation and muscle weakness. Skeletal muscle regeneration is a process that involves the coordinated effort of myogenic regulatory factors (MRFs), inflammatory signaling, and extracellular matrix (ECM) remodeling for optimal regeneration. It has been demonstrated that obesity and aging have a reduction in muscle regeneration. It has not been examined if sarcopenic obesity will further reduce muscle mass and the regenerative process. The purpose of this study …


Apparel Design Process: Shifting The Basic Pattern Block Into A New Framework To Fit The Demands Of Post Double Mastectomy Women, Shan Gao Dec 2016

Apparel Design Process: Shifting The Basic Pattern Block Into A New Framework To Fit The Demands Of Post Double Mastectomy Women, Shan Gao

Graduate Theses and Dissertations

Breast cancer is a leading cancer among women today. Mastectomy is one of the most common paths for breast cancer prevention and treatment. However, this treatment path can cause noticeable body changes around the woman’s bust area. Recently more and more post mastectomy women are deciding to live without breast reconstruction surgery. This decision referred to as “going flat” or “living flat.” Due to the changed bodies and a lack of information on functional and aesthetic concerns related to clothing, clothing selection becomes difficult for post mastectomy women who choose to “live flat.”

The purpose of this study was to …


Liming Characteristics Of A High-Calcium, Dry Flue Gas Desulfurization By-Product And Its Effects On Runoff Water Quality, Jason Richard Burgess-Conforti Dec 2016

Liming Characteristics Of A High-Calcium, Dry Flue Gas Desulfurization By-Product And Its Effects On Runoff Water Quality, Jason Richard Burgess-Conforti

Graduate Theses and Dissertations

In 2013, only 37% of the 32 million Mg of flue gas desulfurization (FGD) by-products generated in the United States were reused beneficially. If FGD by-products could be used as a beneficial soil amendment, millions of megagrams may be diverted away from surface impoundments and landfills. The purpose of this research was to identify the liming characteristics of a high-Ca dry FGD (DFGD) by-product in comparison to a Class-C fly ash (FA) and reagent-grade CaCO3, and to evaluate the effects of land application to a managed grassland on runoff, plant, and soil quality. Liming characteristics were determined by measuring the …


Fishes As A Template For Reticulate Evolution: A Case Study Involving Catostomus In The Colorado River Basin Of Western North America, Max Russell Bangs Dec 2016

Fishes As A Template For Reticulate Evolution: A Case Study Involving Catostomus In The Colorado River Basin Of Western North America, Max Russell Bangs

Graduate Theses and Dissertations

Hybridization is neither simplistic nor phylogenetically constrained, and post hoc introgression can have profound evolutionary effects. Most studies have focused on tractable model systems, rather than organisms with complicated phylogenetic histories. Finescale Sucker (genus Catostomus) in western North America is recognized as a paradigm of fish hybridization. Yet, its extent of historic and contemporary introgression is largely unstudied, an aspect that impedes the resolution of its phylogeny as a baseline for conservation. To explore reticulation in this group, I assayed variation of 20 Catostomus species across temporal and geographic scales by analyzing hundreds of samples and employing a combination of …


Effects Of Acute Heat And Oxidative Stress On The Hepatic Expression Of Orexin And Its Related Receptors, Stephanie Khaldi Dec 2016

Effects Of Acute Heat And Oxidative Stress On The Hepatic Expression Of Orexin And Its Related Receptors, Stephanie Khaldi

Graduate Theses and Dissertations

It is widely known that orexin A and B peptides as well as their receptors are expressed in the hypothalamus and distributed throughout the central nervous system, but there have been few studies regarding its presences in other parts of the body. There is now evidence that orexin (ORX) and its receptors (ORXR1/2) are present in the avian liver; however, their regulation under different environmental conditions is still unknown. In the current study, we sought to determine the effects of heat and oxidative stress using hydrogen peroxide (H2O2) and 4-hydroxynonenal (4-HNE) on the hepatic expression of ORX and ORXR1/2 in …


Daily Variability Of Body Weight And Hydration Markers In Free Living Men And Women, Lynndee Grace Summers Dec 2016

Daily Variability Of Body Weight And Hydration Markers In Free Living Men And Women, Lynndee Grace Summers

Graduate Theses and Dissertations

Body weight and hydration markers change greatly during strenuous exercise, especially in the heat. However, in a non-athletic population, changes in body weight and hydration markers may not be so obvious. It is important to classify the normal fluctuation of these measurements for future studies in order to delineate when an intervention results in a change outside of what can be expected during normal daily living. PURPOSE: The purpose of this study was to describe the normal fluctuations in body weight and urine hydration markers over the course of 29 days. METHODS: One-hundred two male and female participants, ranging from …


Interactive Physics And Characteristics Of Photons And Photoelectrons In Hyperbranched Zinc Oxide Nanostructures, Garrett Edward Torix Dec 2016

Interactive Physics And Characteristics Of Photons And Photoelectrons In Hyperbranched Zinc Oxide Nanostructures, Garrett Edward Torix

Graduate Theses and Dissertations

As is commonly known, the world is full of technological wonders, where a multitude of electronic devices and instruments continuously help push the boundaries of scientific knowledge and discovery. These new devices and instruments of science must be utilized at peak efficiency in order to benefit humanity with the most advanced scientific knowledge. In order to attain this level of efficiency, the materials which make up these electronics, or possibly more important, the fundamental characteristics of these materials, must be fully understood. The following research attempted to uncover the properties and characteristics of a selected family of materials. Herein, zinc …


Perceptions Of Division I Athletic Director Career Paths, Eric A. Wood Dec 2016

Perceptions Of Division I Athletic Director Career Paths, Eric A. Wood

Graduate Theses and Dissertations

There is increased information about the profile of current collegiate athletic directors as it relates to education, age, race, and gender. However, there is a gap in the knowledge of the career paths of the modern day Division I collegiate athletic director position compared to the athletic directors studied over 20 years ago. There is also a gap in the knowledge of the skills necessary to be an effective athletic director from the perspective of Division I athletic directors. The purpose of this study was to use the Perceptions of Division I Athletic Director Career Paths (PADCP) scale to determine …


Growth Of Gesn And Gepb Alloy Films Using Thermal Evaporator, Hakimah Alahmed Dec 2016

Growth Of Gesn And Gepb Alloy Films Using Thermal Evaporator, Hakimah Alahmed

Graduate Theses and Dissertations

Silicon is the most important semiconductor material used in microelectronic devices. As the number of transistors keep doubling every 24 months (Moore’s law), transistors continue scaling down in size, electrical interconnect is reaching its limits to keep up with the scaling down rate in integrated circuits. These limitations are related to interconnect density and power consumption. Hence, replacing electrical interconnect with optical interconnect on the chip or between chips has the ability to overcome these limitations. However, silicon has poor light emitting efficiency, and other substitutes such as III-V materials are not suitable due to high cost, lattice mismatch, and …


Cover Crop Establishment And Potential Benefits To Arkansas Farmers, Ashley Elizabeth Humphreys Dec 2016

Cover Crop Establishment And Potential Benefits To Arkansas Farmers, Ashley Elizabeth Humphreys

Graduate Theses and Dissertations

Soybean farmers in Arkansas need best management practices (BMPs) that maximize the benefits of using cover crops including planting date and fertilization recommendations. An evaluation of cover crop species, planting dates, seeding rates, fertilizer rates, and N accumulation aids in providing these BMPs. The first objective of this research is to assess the effect of planting date on biomass production, as well as looking at the interaction of seeding rate or fertilizer rate for legumes or non-legumes, respectively, using Austrian winter pea (Pisum sativum), cereal rye (Secale cereale), black oats (Avena strigosa), wheat (Triticum aestivum), and tillage radish (Raphanus sativus). …


The Effects Of Anthropogenic Stressors On Mercury Concentrations And Community Composition Of Freshwater Zooplankton, Meredith Powers Jordan Dec 2016

The Effects Of Anthropogenic Stressors On Mercury Concentrations And Community Composition Of Freshwater Zooplankton, Meredith Powers Jordan

Dissertations and Theses

Methylmercury (MeHg) bioaccumulation in freshwater aquatic systems is impacted by anthropogenic stressors, including climate change and excess nutrients. The goal of this study was to determine how warmer water temperatures and excess nutrients would impact zooplankton communities and phytoplankton concentrations, and in turn increase or decrease MeHg concentrations in freshwater zooplankton. I used a 2x2 factorial design to determine if the interaction of temperature and nutrients would impact plankton metrics and zooplankton MeHg concentrations. Mesocosms were filled with Hg-contaminated water and plankton from Cottage Grove Reservoir, Oregon, a waterbody that has experienced decades of elevated MeHg concentrations and corresponding fish …