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Geology And Paleontology Along Part Of The Niobrara River In Northern Nebraska, Robert Matthew Joeckel, S. T. Tucker, Leslie M. Howard

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Exploring The Development Of Core Teaching Practices In The Context Of Inquiry-Based Science Instruction: An Interpretive Case Study, Jill Mcnew-Birren, Leigh A. Van Den Kieboom

College of Education Faculty Research and Publications

This paper describes our reflection on a clinical-based teacher preparation program. We examined a context in which novice pre-service teachers and a mentor teacher implemented inquiry-based science instruction to help students make sense of genetic engineering. We utilized developmental models of professional practice that outline the complexity inherent in professional knowledge as a conceptual framework to analyze teacher practice. Drawing on our analysis, we developed a typography of understandings of inquiry-based science instruction that teachers in our cohort held and generated a two dimensional model characterizing pathways through which teachers develop core teaching practices supporting inquiry-based science instruction.

Anaplasma Phagocytophilum Infection Modulates Expression Of Megakaryocyte Cell Cycle Genes Through Phosphatidylinositol-3-Kinase Signaling, Supreet Khanal, Hameeda Sultana, John D. Catravas, Jason A. Carlyon, Girish Neelakanta

Biological Sciences Faculty Publications

Anaplasma phagocytophilum, the agent of human granulocytic anaplasmosis infects neutrophils and other cells from hematopoietic origin. Using human megakaryocytic cell line, MEG-01, we show that expression of cell cycle genes in these cells are altered upon A. phagocytophilum infection. Expression of several cell cycle genes in MEG-01 cells was significantly up regulated at early and then down regulated at later stages of A. phagocytophilum infection. Lactate dehydrogenase (LDH) assays revealed reduced cellular cytotoxicity in MEG-01 cells upon A. phagocytophilum infection. The levels of both PI3KCA (p110 alpha, catalytic subunit) and PI3KR1 (p85, regulatory subunit) of Class …

Large Marine Protected Areas Represent Biodiversity Now And Under Climate Change, T. E. Davies, S. M. Maxwell, K. Kaschner, C. Garilao, N. C. Ban

Biological Sciences Faculty Publications

Large marine protected areas (>30,000 km²) have a high profile in marine conservation, yet their contribution to conservation is contested. Assessing the overlap of large marine protected areas with 14,172 species, we found large marine protected areas cover 4.4% of the ocean and at least some portion of the range of 83.3% of the species assessed. Of all species within large marine protected areas, 26.9% had at least 10% of their range represented, and this was projected to increase to 40.1% in 2100. Cumulative impacts were significantly higher within large marine protected areas than outside, refuting the …

Noninvasive Measures Of Stress And Lameness In Broilers, Shawna L. Weimer

Graduate Theses and Dissertations

The concept of broiler chicken welfare has evolved from a component of animal husbandry to a label on a chicken product package. Recent attention from the public has led to the need for higher welfare standards for animal production. A primary concern of broiler production is low activity/locomotion attributed to fast growth rates leading to poor leg health. To collect the scientific data necessary to determine conditions providing the best welfare for the bird, multiple methods of assessment are required. Stress is influenced by external (temperature, humidity, lighting, stocking density) and internal (metabolism, thermoregulation, hormonal balance) factors. This series of …

Membranes For Food And Bioproduct Processing, Alexandru Marius Avram

Graduate Theses and Dissertations

Modified membranes for process intensification in biomass hydrolysis

Production of biofuels and chemicals from lignocellulosic biomass is one of the leading candidates for replacement of petroleum based fuels and chemicals. However, conversion of lignocellulosic biomass into fuels and chemicals is not cost effective compared to the production of fuels and chemicals from crude oil reserves. Some novel and economically feasible approaches involve the use of ionic liquids as solvents or co-solvents, since these show improved solvation capability of cellulose over simple aqueous systems. Membranes offer unique opportunities for process intensification which involves fractionation of the resulting biomass hydrolysate leading to …

Evaluating The Policies That Lead To Stem Educational Attainment At The University Of Arkansas For Transfer Students, Bryan Hill

Graduate Theses and Dissertations

The US has a critical need to produce more STEM graduates and that need is exponentially more critical in Arkansas. Arkansas currently ranks last in the percent of STEM degrees conferred compared to overall degrees awarded. Students intending to pursue a STEM four-year college degree who start at a two-year college are significantly less likely to succeed in earning that degree. Arkansas passed Acts 672 and 182 aimed at strengthening the success of students who transfer from two-year colleges into four-year institutions. This study sought to evaluate the effectiveness of the Acts by determining if the University of Arkansas (UA) …

Evaluating One-Step Catalytic Free Method Including Hydrolysis, Esterification, Transesterification, And Degradation Reactions To Produce Biodiesel From Soybean Oil, Mahmood Gheni Jebur

Graduate Theses and Dissertations

Due to the environmental and economic impacts of diesel fuel based on petroleum, several studies have been done to find an alternative source of energy. Biodiesel is considered one of these alternative sources. It is a renewable source of energy produced from vegetable oils and animal fats. There are two main reaction routes used to produce biodiesel (fatty acid methyl esters). Transesterification reaction is the first route used to convert triglycerides to fatty acid methyl esters (FAMEs), while hydrolysis followed by esterification reactions are the second route employed to convert triglycerides to free fatty acids (FFA) and then further converted …

Removal Of Endocrine Disrupting Compounds Using Membrane Bioreactor, Mohanad Ali Abdulsahib Kamaz

Graduate Theses and Dissertations

The presence of endocrine disrupting compounds (EDCs) and pharmaceutically active compounds (PhAC) such as pesticides, personal care products, antibiotics and pharmaceutical compounds, in sewage, industrial, and domestic waters has extensively become the major concern for health and environmental organizations. These compounds have the ability to interact with mammalian endocrine system and disrupting their functions. The traditional activated sludge processes are designed to degrade solids, organic carbon and nitrogen loading. Although several treatment steps in a wastewater treatment plant can contribute to partial removal of EDCs, effective removal has been a challenge due to their resistant chemical and biological degradation and …

Peptide-Directed Nanoparticle Synthesis With A Denovo Pd-Binding Sequence Fused To A Reporter Protein, Rita Eloisa Tejada Vaprio

Graduate Theses and Dissertations

There is a need for low-cost nanoparticle materials in the context of new technologies for catalyst development. The purpose of this work was to recombinantly produce a 45- amino acid long metal binding peptide that is useful for nanoparticle synthesis. Using splicing by overlap extension PCR, a synthetic gene containing the fusion of the metal binding peptide with Green Fluorescent Protein (GFPUV) was constructed. The metal binding peptide, fused to reporter protein GFPUV, was expressed using high cell density fermentation. Palladium nanoparticles of an average diameter of 1.18 0.45 nm were synthesized by using the crude cell extract containing the …

Modeling Ozark Caves With Structure-From-Motion Photogrammetry: An Assessment Of Stand-Alone Photogrammetry For 3-Dimensional Cave Survey, Joseph H. Jordan

Graduate Theses and Dissertations

Nearly all aspects of karst science and management begin with a map. Yet despite this fact, cave survey is largely conducted in the same archaic way that is has been for years - with a compass, tape measure, and a sketchpad. Traditional cave survey can establish accurate survey lines quickly. However, passage walls, ledges, profiles, and cross-sections are time intensive and ultimately rely on the sketcher’s experience at interpretively hand drawing these features between survey stations.

This project endeavors to experiment with photogrammetry as a method of improving on traditional cave survey, while also avoiding some of the major pitfalls …

Evaluating Thermal Comfort Of Broiler Chickens During Transportation Using Heat Index And Simulated Electronic Chickens, Kaushik Luthra

Graduate Theses and Dissertations

Broilers experience high physiological stress during pre-slaughter transport, especially under extremes of thermal environment. Characterization of thermal environment on the trailer is crucial to identify stress-prone regions during transportation. At the same time, Broilers experience high physiological stress during pre-slaughter transport, especially under extremes of thermal environment. Characterization of thermal environment on the trailer is crucial to identify stress-prone regions during transportation. At the same time, quantification of heat loss of the broilers loaded on trailers is important in understanding the well-being of the broilers. We have developed four electronic chickens (E-chickens) to simulate the sensible heat loss of live …

Factors Contributing To The Success Of First-Generation College Students At A Research University, Mary Margaret Hui

Graduate Theses and Dissertations

First-generation college students are students whose parents do not have a college degree, and they face numerous barriers in college. Yet, several first-generation college students (FGCS) are successful and are on-track to graduate with a bachelor’s degree in four years. Their success is important because education is associated with increased income, quality of life, and social mobility, making educational attainment even more significant in Arkansas, which has both low educational attainment and high poverty. Little is known about what can be done to close the achievement gap. It is important to analyze what helped FGCS succeed so that higher education …

Bee Communities On Managed Emergent Wetlands In The Lower Mississippi Alluvial Valley Of Arkansas, Phillip Lee Stephenson

Graduate Theses and Dissertations

Native bee communities that use emergent wetlands are among the least studied systems in bee research. Most native bee species are thought to be in decline based on the loss of usable habitat across the United States. I surveyed emergent wetlands in the lower Mississippi Alluvial Valley of Arkansas during the summers of 2015 and 2016 using pan traps, blue-vane traps, and sweep nets to determine the current status of bee communities in this system. I surveyed 11 sites in 2015 and 17 sites in 2016 and found that bee communities were similar in actively versus passively managed emergent wetlands. …

The Impact Of Social Situations On College Students’ Perceptions Of Sexual Consent, Casey Jane Ward

Graduate Theses and Dissertations

The majority of research examining sexual consent among college students focuses on how young adults communicate sexual consent during interactions immediately preceding a sexual encounter. However, preliminary research suggests that college students perceive that individuals begin to communicate sexual consent within social settings (e.g., at a bar) and through nonsexual interactions (e.g., text messaging); this has been labeled “outside the bedroom” consent. In order to further explore “outside the bedroom” consent, college students (n= 789) were randomly assigned to read four of sixteen vignettes. Within each vignette, four variables were manipulated: gender of the initiator (male or female), the social …

Rna Sequencing In The Development Of Cancer-Cachexia, Thomas Allen Blackwell

Graduate Theses and Dissertations

Introduction: Cancer is a major public health problem in the U.S. and the world. In 2013 there were an estimated 1,660,290 new cases of cancer in the U.S. Cancer-Cachexia (CC) is a common effect of many cancers, and is directly responsible for 20-40% of cancer-related deaths. The mechanisms that control the development of CC are not well understood. Most investigations of CC focus on the post-cachectic state and do not examine the progression of the condition. The purpose of this study was to utilize RNA sequencing to analyze transcriptomic alterations throughout the progression of CC. Methods: Lewis Lung Carcinoma cells …

From Foster Care To College: Student Stories Of Success, Tory Nicole England

Graduate Theses and Dissertations

The purpose of this qualitative study was to understand the different factors that empower young adults that were in foster care to be successful in a college environment. It has been documented that foster youth have significant challenges during secondary education (Conger & Rebeck, 2001; Geenen & Powers, 2006). Due to these challenges, foster youth attend and graduate higher education at a lower rate than their peers. The perspectives of foster youth currently enrolled in higher education is critical to determining which factors and programs have helped with their educational success. Five participants completed semi-structured interviews about their secondary education, …

Experiment-Based Quantitative Modeling For The Antibacterial Activity Of Silver Nanoparticles, Mohammad Aminul Haque

Graduate Theses and Dissertations

Silver (Ag) has been well known for its antimicrobial activity for a long time. Recent research showed the potential of Ag nanoparticles as emerging antimicrobial agents. However, little quantitative analysis has been performed so far to decipher the mechanism of interaction between nanoparticles and bacteria. Here, a detailed analysis based on kinetic growth assay and colony forming unit assay has been carried out to study the antimicrobial effect of Ag nanoparticles against Escherichia coli (E. coli) bacteria. It was observed that the presence of Ag nanoparticles increased the lag time of bacterial growth while not affecting the maximum growth rate …

Interactive Effects Of Flow Regime, Climate Change, And Angler Harvest On Smallmouth Bass At The Southern Range Extent, Christopher Middaugh

Graduate Theses and Dissertations

The Ozark-Ouachita Interior Highlands of Arkansas, Oklahoma, and Missouri are the southern extent of native Smallmouth Bass Micropterus dolomieu range. Smallmouth Bass are an important species economically and ecologically, but it is unknown how climate change may affect them in this region and in particular how Smallmouth Bass may be affected differently across streams from various flow regimes. Here I present three projects investigating how climate change, flow regime, and angler harvest may interact to affect Smallmouth Bass over the coming century. I first modeled present and future water temperatures and calculated growth rate potential for Smallmouth Bass from streams …

Growth And Survivability Of Microorganisms At Martian Temperatures And Pressures, Rebecca Lynne Mickol

Graduate Theses and Dissertations

The discovery of methane in the martian atmosphere via numerous ground- and space-based sources has prompted the study of methanogens as models for life on Mars. Methanogens are microorganisms within the domain Archaea, many of which utilize carbon dioxide (CO2) and hydrogen to produce methane. The non-photosynthetic nature of methanogens indicates that they could exist in sub-surface environments, protected from harmful UV and ionizing radiation on the surface of Mars. These organisms also do not require organics, which are sparse on the planet.

Additionally, the wide variety of environments we find life in on Earth, as well as evidence for …

Instrumental Aspects Of Oxygen Sensing: Quantitation And Recalibration Of A Biofouled Oxygen Sensor, Marlena Patrick

Graduate Theses and Dissertations

In vivo oxygen sensing is a critical area of research for medical applications, such as ischemic stroke, but this important topic is not fully understood or resolved. In addition, the best method for calibration of in vivo sensors is as yet undetermined. For all implantable devices, biofouling, the adsorption of biological material to the device surface, is another significant problem with no clear or well-defined solution. One method employed is to apply a protective polymer membrane to the sensor surface in order to minimize the adsorption of biological material. The work described here investigates two polymers applied to a gold …

Curricular Analysis Of The University Of Arkansas Composition I Pilot Course: Engl 1013, Community Ethnography, Morgan Lindsay Scholz

Graduate Theses and Dissertations

This thesis analyzes a new first-year writing course that is under consideration for implementation as the standard Composition I course at the University of Arkansas. The course utilizes an ethnographic approach to teaching critical writing skills to students. This thesis presents evaluation through a metacognitive lens and explores the course through a case study approach. This thesis also examines the expectations and concluding reflections of three stakeholder groups: students, instructors, and administrators.

Mushroom Inoculation On Switchgrass Feedstock During Storage: Effects Of Subsequent Pre-Processing For Intended Biofuels Production, Amandeep Singh Turay

Graduate Theses and Dissertations

The objective of this project was to examine the effect of fungal treatment and liquid hot water pretreatment of switchgrass combine in view of increasing glucose release. The fungal treatment consisted of incubating Pleurotus ostreatus in square switchgrass bales, at 50% moisture content for 25 days, 54 days, and 82 days. The digestibility of the switchgrass biomass was subsequently evaluated using Accelerase 1500 enzyme. Lignin is an important barrier to enzymatic hydrolysis, and it was stipulated that incubation with P. ostreatus would disrupt plant cell walls, resulting in enhanced saccharification. Three different concentrations of P. ostreatus were evaluated: 0%, 2%, …

Characterization Of The Thermal Environment During Transport Of Commercial Broiler Chickens, Douglas J. Aldridge

Graduate Theses and Dissertations

Transport of commercial broiler chickens from the farm to the processing plant is perceived to compromise welfare under some circumstances. Research has been conducted using European standard equipment to characterize the environment experienced by poultry during broiler transport. In contrast no studies have been reported on the environment experienced by broilers under United States standard industry practices during transport. Moreover, microenvironment temperatures within industry trailers have not been reported.

The present study characterized the thermal micro-environment experienced by broiler chickens during transport across different seasons. The temperatures were influenced by temperature mitigation practices (plastic wrap, double side board, single side …

Effects Of Northern Bobwhite Management On Raccoon Abundance, Habitat Selection, And Home Range In Southwest Missouri, Jacob Cody Mcclain

Graduate Theses and Dissertations

Habitat management has become vital for northern bobwhite (Colinus virginianus) conservation. In Missouri, efforts to conserve remaining populations on public lands have included the use of two management models. The Intensive Management Model (IMM) promotes hard edges, by creating a juxtaposition of different habitat types, while the Extensive Management Model (EMM) maintains a grassland-dominated landscape through the processes of fire and grazing. Preliminary results suggest that bobwhite success is significantly higher on EMM sites than IMM sites. Management efforts through IMM may be hindered by unintentionally managing for nest predators like raccoons (Procyon lotor). Nest predators may forage more often …

Peptoid-Based Microsphere Coatings For Use As Tunable Biocompatible Interfaces, German Raul Perez Bakovic

Graduate Theses and Dissertations

The pursuit of sensitive, non-invasive, and cost efficient diagnostic tools for early stage disease detection have led to the development of sophisticated biosensor technologies for proteomic studies. As these markers increase in complexity, the role of support substrates grows increasingly important. Limitations in existing support substrates include the potential for increased sensitivity, binding specificity, and bio-stability. Ideal support substrates need to provide biocompatible and bioresistant surfaces, that offer high surface areas for binding, and enables the incorporation of diverse chemistries. The use of peptoids as the basis for the deposition of uniform microsphere coatings offers a mean to the attainment …

Supplemental Trace Minerals (Zn, Cu, And Mn) As Sulfates Or Hydroxy Trace Mineral Sources For Beef Heifers, Randy Hunter Burnett

Graduate Theses and Dissertations

Crossbred heifers (n = 286, 255 ± 4.5 kg initial BW, 295 ± 16.5 d of age) were used over a 2-yr period to determine the effects of mineral source on beef heifer development at 2 locations (n = 71 and n = 72, Fayetteville, blocks 1 and 4; n = 72 in each of 2 breeding groups, Batesville, blocks 2 and 3). Heifers were stratified based on initial BW, age, health, prior research projects, and sire, and then assigned to 6 groups of 12 heifers, that were assigned randomly to 1 of 2 trace mineral treatments. The 2 treatments …

A Comparative Analysis Of Feed And Environmental Factors On Broiler Growth In The United States, Alexandra Gulli

Graduate Theses and Dissertations

Broiler production in the United States has become an important industry within the last half century. As the demand for poultry continues to increase and the concern of climate change also increases, it will become an important part of the industry to become more sustainable. This study uses a feed optimization model, a broiler growth model, and a life cycle assessment (LCA) to determine how feed ingredients and the barn environment can affect the broiler’s growth and production emissions. A multi-criteria ration optimization model is used to produce feeds based on carbon footprint and cost. A growth model is used …

Evaluating Methods For Quantifying Evapotranspiration In Arkansas Rice, Colby Reavis

Graduate Theses and Dissertations

The goal of this study was to evaluate different methods for quantifying evapotranspiration (ET) in commercial rice fields using different irrigation regimes. The rice fields were located in south central Arkansas. The different irrigation regimes were alternate wetting and drying (AWD) and continuous flooding (CF). Alternate wetting and drying and conventional flooding estimates of ET were 602 mm and 570 mm, respectively, based on field observations using eddy covariance. Models used to estimate ET estimated values between 498 and 653 mm for the 2015 growing season. The Penman Monteith actual evapotranspiration model (PM AET) performed best when compared to the …

Phylogenetic Diversity Of The Bacterial Communities In Craft Beer, Lindsey Rodhouse

Graduate Theses and Dissertations

The craft beer industry is increasing in popularity in the United States. The craft brewing process typically does not use a pasteurization step, therefore the boiling process is the primary critical control step. Any microorganisms introduced after boiling, or those that are not killed during boiling, are likely to participate in fermentation and persist in the final product. Previous culture-based studies have isolated bacteria and yeast from craft beers at specific time points, but little research has been done on the process as a whole. The objectives of this research are to (1) track bacteria development throughout the brewing process …