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Local Extinction Of A Rare Plant Pollinator In Southern Utah (Usa) Associated With Invasion By Africanized Honey Bees, Allen Szalanski

Entomology and Plant Pathology Faculty Publications and Presentations

Twenty-five years ago, Arctomecon humilis, a pollinator-dependent, endangered poppy globally restricted to the extreme northeastern Mojave Desert in southwestern Utah, was pollinated by native bee species and the European honey bee. Follow-up studies beginning in 2012 failed to find the two most important native bee pollinator species, one of which, Perdita meconis, is a strict poppy specialist. We had four objectives: (1) confirm the status of formerly important native bee pollinators; (2) determine the role of the Africanized honey bee which reportedly invaded southern Utah in 2008; (3) examine the effect of the ostensible change in pollinator fauna on fruit …

Mitochondrial Dna Variation Of Feral Honey Bees (Apis Mellifera L.) From Utah (Usa), Allen Szalanski

Entomology and Plant Pathology Faculty Publications and Presentations

A study was conducted on the mitochondrial DNA genetic diversity of feral colonies and swarms of Apis mellifera from ten counties in Utah by sequencing the intergenic region of the cytochrome oxidase (COI-COII) gene region. A total of 20 haplotypes were found from 174 honey bee colony samples collected from 2008 to 2017. Samples belonged to the A (African) (48%); C (Eastern Europe) (43%); M (Western Europe) (4%); and O (Oriental) lineages (5%). Ten African A lineage haplotypes were observed with two unique to Utah among A lineage haplotypes recorded in the US. Haplotypes belonging to the A lineage were …

Poultry Industry, Allen Szalanski

Entomology and Plant Pathology Faculty Publications and Presentations

Cimicids, and particularly the Common bed bug, Cimex lectularius L., can infest poultry houses and cause severe cutaneous reactions in the birds as wellas other clinical effects. This chapter discusses some cimicids that have been documented as pests of poultry, including: the Mexican chicken bug, Haematosiphon inodorus (Duges); the Brazilian chicken bug, Ornithocoris toledoi Pinto; the related species, Ornithcorus pallidus Usinger; and and the Tropical bed bug, Cimex hemipterus (F.).

Arkansas Water Resources Center Annual Technical Report, 2017, Arkansas Water Resources Center

Arkansas Water Resources Center Annual Report

No abstract provided.

Methods And Compositions For X-Ray Induced Release From Ph Sensitive Liposomes, Daniel Fologea, Ralph Henry, Greg J. Salamo, Yuriy Mazur, Michael J. Borrelli

Patents Granted

Compositions including pH sensitive lipid vesicles comprised of a lipid layer, an agent, and an organic halogen such that the agent is released from the vesicles after exposure to ionizing radiation. Methods of delivering the agent to a target in a subject using the compositions provided herein are also described. The methods allow for controlled release of the agent. The timing of release of the agent from the lipid vesicle may be controlled as well as the location of release by timing and localizing the exposure to ionizing radiation exposure.

An Experiment-Based Model Quantifying Antimicrobial Activity Of Silver Nanoparticles On Escherichia Coli, Mohammad A. Haque, Riku Imamura, George A. Brown, Venkata R. Krishnamurthi, Isabelle I. Niyonshuti, Tiffany Marcelle, Leanne E. Mathurin, Jingyi Chen, Yong Wang

Physics Faculty Publications and Presentations

Silver nanoparticles (AgNPs) are well known to exhibit antimicrobial effects through plausible interactions with proteins and/or deoxyribonucleic acid inside the bacteria. Yet a quantitative understanding on the antimicrobial activities of AgNPs remains obscure. Here we conducted in-depth kinetic growth assays and colony-forming unit (CFU) assays on Escherichia coli (E. coli) cultured in AgNPs or Ag ion-containing growth media. Compared to the Ag-absent culture medium, it was found that the growth rate of the bacteria remained unaffected but the lag time of the bacterial growth was extended due to the presence of AgNPs or Ag ions. From the CFU-based time-kill curves, …

Mole Street Journal, December 2017, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Effects Of Uniaxial Cyclic Strain On Endothelial Progenitor Cells, Maria Alejandra Zeballos Castro

Biomedical Engineering Undergraduate Honors Theses

Despite the high prevalence of calcific aortic valve disease (CAVD), the underlying mechanisms of pathogenesis have not been found yet. Therefore, it is extremely important to study CAVD and understand how it develops. For this matter, we decided to study the potential of endothelial progenitor cells (EPCs) for use in tissue-engineered models of heart valves. EPCs were chosen as the cell source of interest for this study due to their high neovascularization potential and use in regenerative medicine and cardiovascular tissue engineering.

In this project, we aimed to engineer the microenvironment of cells that are involved in the formation of …

Profitability Analysis Of Varying Herd Sizes Based On Price Signals In Cow-Calf Operations, Colson Tester

Agricultural Economics and Agribusiness Undergraduate Honors Theses

The third most consumed meat around the world is beef. Despite global growth in demand, cattle markets experience price cycles related to biological production lags causing variability in cash flow and profitability for producers. Price-driven herd size management strategies thus have received attention. This study adds to that literature by analyzing both price and production risk using three herd size management strategies: i) steady state – holding herd size constant; ii) dollar cost averaging – keeping reinvestment constant by varying the number of replacement heifers retained at a constant long run average dollar total; and iii) moving average – using …

An Investigation Of Biological Carbon Sequestration At The Pea Ridge National Military Park, Dorine Reed Bower

Graduate Theses and Dissertations

The direct correlation between increasing levels of atmospheric CO2 and global temperatures is now irrefutable. A 50% increase in atmospheric CO2 levels from a pre-industrial level of 270 ppm to a present-day level of 405 ppm, has resulted in documented record temperatures and a concomitant rising of sea levels from melting ice caps.

The ability of biological/terrestrial ecological systems to store atmospheric carbon is a viable option in the effort to mitigate the climate impacts of rising anthropogenically-caused greenhouse gas emissions. Components of the vegetation and soils in the Pea Ridge National Military Park (the Park) were examined for carbon …

3d Printed Pcu/Uhmwpe Polymeric Blends For Artificial Knee Meniscus, Raissa Araujo Borges

Graduate Theses and Dissertations

3D printing was used to fabricate porous artificial knee meniscus material from biocompatible polymeric blends of polycarbonate-urethane (PCU) and ultra-high-molecular-weight polyethylene (UHMWPE) to enable “weep” lubrication that mimics the native meniscus. 3D printed and molded pure PCU, as well as molded PCU and UHMWPE, were used for comparison. Preliminary printing was done to evaluate the impact of process parameters on the results. The samples were subject to a variety of rotational oscillating friction and wear tests under simulated body fluid and loading conditions to replicate the natural motion of the knee. Results show that 3D printed PCU samples yielded a …

Investigating Fate Of Silver Nanoparticles In Wastewater Biofilms, Connie Marie Walden

Graduate Theses and Dissertations

As industrial advances make everyday life easier for human kind, the processes by which we need to maintain sanitary conditions for both water and wastewater treatment will become increasingly complex. Innovations in food packaging and textile design incorporate engineered nanoparticles (ENPs) to increase antimicrobial properties of clothing, maintain product color, and keep food in packaging from spoilage. For most products, ENPs released will enter the sanitary sewer system, and ultimately wastewater treatment plants. Biofilms grow universally on surfaces where a protective layer of extracellular polymeric substances (EPS) shields attached cells from stressors. In wastewater treatment, complex biofilms are utilized as …

The Blight Of The Bumblebee: How Federal Conversation Efforts And Pesticide Regulations Inadequately Protect Invertebrate Pollinators From Pesticide Toxicity, Emily Helmick

Journal of Food Law & Policy

This article explores the Endangered Species Act's conservation efforts towards the Rusty-Patched Bumblebee as a case study that highlights the gaps in protections afforded to invertebrate pollinators. It focuses on how the law does not adequately protect endangered invertebrate pollinators from inadvertent pesticide poisoning and introduces the threat that this poses to our food system.

Influence Of Social And Economic Factors On Elementary Student Health In Northwest Arkansas, Megan Marks

The Eleanor Mann School of Nursing Undergraduate Honors Theses

A child’s wellbeing is influenced by many factors related to the environment they are raised in. The purpose of this study was to investigate the relationship between a child’s social and economic factors and his or her health. A convenience sample of 588 2nd and 4th grade children was taken from three elementary schools in Springdale Independent School District. Health status was represented by calculations of each child’s body mass index (BMI) and number of days counted absent from school. Socioeconomic and demographic factors examined include the child’s grade level, gender, ethnicity, number of parents over the household, number of …

Modifiable Factors Impeding Nurses’ Willingness To Report In A Disaster, Kate Hutchison

The Eleanor Mann School of Nursing Undergraduate Honors Theses

This research project investigates what modifiable factors impede nurses’ willingness to report to work during a disaster. The survey sample were nurses in the United States. Survey methodology was a snowball sampling initiated among nurses attending a PhD Program at the University of Texas at Tyler as well as the utilization of Facebook to recruit participants. The survey instrument determined likelihood of nurses reporting to work in various types of disasters and factors that may impede them from responding to such disasters. The online survey asked thirty-five “select all that apply” type questions and the results will be used to …

The Effect Of Preflood Nitrogen And Flood Establishment Timing On Rice Development, Nitrogen Uptake And Grain Yield, Tyler Richmond

Graduate Theses and Dissertations

Urea-N fertilizer is typically applied at the 5-leaf stage to rice (Oryza sativa L.) grown in a dry-seeded, delayed-flood production system. How long the preflood-N can be delayed without adverse effects on yield potential is poorly understood. The research objective was to determine the effects of preflood-N application and flood establishment timing on aboveground-N content, 50% heading, yield components, and grain yield. Trials were established on silt loam soils at the Pine Tree Research Station (PTRS) and Rice Research and Extension Center (RREC) during 2015 and 2016. Urea-N was applied at 0, 45, 90, 135, and 180 kg N ha-1 …

Effect Of Endophyte-Infected Tall Fescue Toxins On Growth Performance And The Microbial Community In The Rumen And Feces In Pregnant Ewes, Saleh Alrashedi

Graduate Theses and Dissertations

Fifty pregnant Katahdin ewes grazed pastures with high (HE) and moderate (MI) levels of Neotyphodium coenophialum-infected tall fescue between February 1 and May 24 to determine the impacts of tall fescue toxins on body weight (BW), body condition scores, FAMACHA scores, fecal egg counts (FEC), and serum Cu, Zn, prolactin, and non-esterified fatty acids (NEFA). Within those 50 ewes, 15 were selected randomly for fecal and rumen sampling to assess the impacts of HE and MI on the microbiome community. Total bacterial DNA was extracted from rumen and fecal samples, and alpha and beta diversities were used to relate microbiome …

Fungi Of Forests: Examining The Diversity Of Root-Associated Fungi And Their Responses To Acid Deposition, Donald Jay Nelsen

Graduate Theses and Dissertations

Global importance of forests is difficult to overestimate, given their role in oxygen production, ecological roles in nutrient cycling and supporting numerous living species, and economic value for industry and as recreational zones. Fitness of the forest-forming trees strongly depends on microbial communities associated with tree roots. In particular, fungi impact tree fitness: mycorrhizal species provide water and nutrients for the trees in exchange for C, endophytic fungi play key roles in host defense against pathogenic organisms, and saprotrophic fungi decompose dead organic matter and facilitate nutrient cycling. In addition, pathogenic fungal species strongly affect forest fitness. Despite their importance, …

The Cold War In The Eastern Mediterranean: An Interpretive Global History, James M. Brown

Graduate Theses and Dissertations

This thesis offers the first global history of the Cold War in the eastern Mediterranean. It examines the international linkages that bound Greece, Turkey, and Cyprus with superpowers, non-aligned states, and transnational movements during the second half of the twentieth century, and it considers the effects of such linkages upon the eastern Mediterranean’s domestic arenas. Throughout, it demonstrates that two forces – synthesis of outside influence alongside consolidation of internal identities – dictated the region’s experiences during the Cold War. And though the international environment furnished the conditions within which the region’s societies pursued the project of nation-building, indigenous forces …

Modelling The Impact Of National Development Strategies For The East African Rice Sector, Florence Muthee

Graduate Theses and Dissertations

The 2008 food crisis prompted many food importing nations to reconsider the need to be self-sufficient especially in their staple food needs. This awakening led to the launch of the Coalition for Africa Rice Development (CARD) initiative with a goal to double rice production in Africa. Under the CARD umbrella member countries drafted individual National Rice Development Strategies (NRDS). This study is a quantitative assessment of four East African countries’ NRDS: Kenya, Rwanda, Tanzania and Uganda within dynamic global rice economy models. The NRDS targets and strategies are not realistic and included under estimation of rice consumption for Kenya, an …

Shallow Aggregate Ebb-And-Flow System For Greenhouse Lettuce Production, Joseph Chidiac

Graduate Theses and Dissertations

A novel soilless technique for the production of lettuce was developed and evaluated for its viability for ornamental greenhouse growers adapting their ebb-and-flood irrigation benching systems to diversify into growing lettuce, without having to purchase the conventional nutrient film technique (NFT) or deep flow technique (DFT) hydroponic systems. The experimental design was a three by four factorial, with three treatments for aggregate depth (19, 38, and 57 mm) and four treatments for irrigation frequency (once every 1, 2, 4, or 8 hours), for a total of twelve treatment combinations. Each treatment was replicated three times in a randomized complete block …

Exercise, Cognition, And The Aging Process Among Active, Competitive, And Sedentary Middle-Aged And Older Adults, Katherine Adams

Health, Human Performance and Recreation Undergraduate Honors Theses

Purpose This study aimed to compare the cognitive measures of reaction time and dual-task performance among recreationally active, master athletes, and sedentary older adults aged 50 years or older. Methods 59 late middle-aged and older adults between the ages of 50 to 88 years old participated in reaction time and dual-task tests of which consisted of multiple trials on the same day. Subjects were placed either into the recreationally active, masters athlete, or sedentary activity level group based on the Rapid Assessment of Physical Activity (RAPA) form. For the gait speed with associated dual-task component, subjects walked 10-meters at two …

The Effect Of Interaction With Therapy Horses On University Students' Perceived Stress Level, Alexa Chapman

The Eleanor Mann School of Nursing Undergraduate Honors Theses

This research project investigates how university students are affected by interacting with therapy horses. Stress is the factor that will be evaluated in this particular study. The self-rated stress scores will be acquired from University of Arkansas students both before and after interacting with specially trained therapy horses during an Equine Assisted Activity and Therapy (EAAT) class offered at the University. Stress will be evaluated by students taking a survey inquiring about daily stressors including finances, school, work and relationships. The data collected will be compared by pre- and post- interactions with the horses. We expect that the pre- and …

Transcriptome-Based Gene Networks For Systems-Level Analysis Of Plant Gene Functions, Chirag Gupta

Graduate Theses and Dissertations

Present day genomic technologies are evolving at an unprecedented rate, allowing interrogation of

cellular activities with increasing breadth and depth. However, we know very little about how the

genome functions and what the identified genes do. The lack of functional annotations of genes

greatly limits the post-analytical interpretation of new high throughput genomic datasets. For plant

biologists, the problem is much severe. Less than 50% of all the identified genes in the model plant

Arabidopsis thaliana, and only about 20% of all genes in the crop model Oryza sativa have some

aspects of their functions assigned. Therefore, there is an …

Identifying Genetic Factors Influencing Sperm Mobility Phenotype In Chicken Using Genome Wide Association Studies, Primordial Germ Cell Transplantation, And Rnaseq., Sohita Ojha

Graduate Theses and Dissertations

Sperm mobility is a major determinant of male fertility in chicken. In spite of low heritability of reproductive traits, sperm mobility has high heritability index which suggests presence of quantitative trait loci (QTLs) governing the trait. Our research focused on three objectives: i) to identify the QTLs affecting low mobility phenotype in chicken, ii) to understand the impact of Sertoli-cells and germ cells interactions in influencing the mobility phenotype and iii) to identify the genes and gene networks differentially expressed in male and female PGCs. To detect the QTLs, genome wide association studies (GWAS) was conducted which revealed the presence …

Determination Of The Effects Of Different Maillard Reaction Products On The Taxonomic Composition Of The Gut Microbiota, Nesreen Hamdan Aljahdali

Graduate Theses and Dissertations

The Maillard Reaction (MR) is a non-enzymatic chemical reaction which results in linkage between the amino group of amino acids and the carbonyl group of reduced sugars. This reaction generates Maillard reaction products (MRPs) which are not present naturally in foods, and are responsible for a range of colors, odors, flavors, and other sensory properties. Conflicting reports of MRPs impacts on human health are probably due to the fact that bioconversion of these digestible molecules by the gut microbiota has been marginally taken into account. This study aimed to determine the effects of different MRPs on rodent’s gut microbiota through16S …

Cellular Mechanisms Of Ionoregulation In The Gill Of Japanese Medaka And Rainbow Trout, Rebecca Jo Bollinger

Graduate Theses and Dissertations

Euryhaline fishes are capable of adapting to a wide range of salinities such as freshwater, brackish water or seawater. Through the combined effort of the gill, kidney and intestine, they are able to osmoregulate to maintain a constant internal hydromineral balance. As the gill is in direct contact with the external environment, it is continuously working to maintain ion and acid/base balance, gas exchange and eliminate nitrogenous waste. Fish in freshwater are subjected to osmotic water gain and diffusional ion loss across the gill and experience the opposite in seawater. Therefore, the gill exhibits extreme plasticity when experiencing a change …

Piglet Gut Microbiota Responses To Exposure To Outdoor Simulated Environment And Formula Feeding, Nguyen Vo

Graduate Theses and Dissertations

Several lines of evidence suggest that early-life gut microbiota composition is a crucial determinant of the susceptibility to diseases later in life. Understanding the evolution of early-life gut microbiota and critical factors that can modify this microbial community will espouse the prevention or reversion of health risk originating from dysbiosis of the gut microbiota in the early stage. In this research, we hypothesized that alterations in the environment (simulation of rural conditions by soil exposure) and feeding mode (breastmilk versus formula milk) will have significant impacts on the establishment of the gut microbiota in early life. At first, in literature …

Economic And Policy Evaluations And Impacts Of The National Rice Development Policy Strategies In Malaysia: Self-Sufficiency, International Trade, And Food Security, Roslina Binti Ali

Graduate Theses and Dissertations

Despite the fact that the recent rice policy has been moving to a strategy of self-sufficiency while the status quo of the national rice economy remains ambiguous, Malaysia has made an extreme policy decision to pursue an autarky economy in its rice sector, thus closing borders from the international markets in the future. The goal of this dissertation research is to comprehensively evaluate a deep-rooted rice policy in Malaysia and analyze the holistic impacts of the self-sufficiency and international trade policies at the national and farm-household levels, utilizing economic frameworks. The protectionist policy measures using a Policy Analysis Matrix reveals …

Bacterial And Archaeal Nitrifier Communities After Seven Years Surface Ground Cover And Nutrient Management In An Orchard Soil, Mashael Albalawi

Graduate Theses and Dissertations

Nitrification is oxidation of ammonia to nitrite and subsequently to nitrate. The rate limiting step of nitrification, ammonia oxidation to nitrite, was thought for many years to be carried out primarily by ammonia oxidizing bacteria (AOB). However, using molecular techniques and investigating the amoA gene, ammonia-oxidizing archaea (AOA) were discovered. Understanding how long-term application of surface ground covers and organic fertilizers to perennial systems affect microbial communities is critical for sustainable soil management. An organically managed experimental apple orchard soil received seven years (2006 – 2013) of annual, surface applications of poultry litter or commercial fertilizer compared to no fertilizer …