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Effects Of Associated Subcortical Beetles On Oviposition Behavior And Early-Stage Survival Of Sirex Nigricornis F. (Hymenoptera: Siricidae), Ace J. Lynn-Miller Dec 2012

Effects Of Associated Subcortical Beetles On Oviposition Behavior And Early-Stage Survival Of Sirex Nigricornis F. (Hymenoptera: Siricidae), Ace J. Lynn-Miller

Graduate Theses and Dissertations

Sirex (Hymenoptera: Siricidae) woodwasps develop within xylem of host conifers. Sirex females drill through the bark, phloem and into xylem tissues where they deposit eggs along with a symbiotic Amylostereum fungus. The presence of Amylostereum is necessary for successful development of Sirex immatures as the larvae are unable to derive adequate nutrition from xylem in the absence of the fungus. The Eurasian woodwasp, Sirex noctilio F., was discovered in northeastern North America in 2004. Sirex noctilio has caused significant economic damage in Pinus radiata D. Don plantations of the southern hemisphere, but is of little economic significance in its native …


Long-Term Effects Of Rice Rotation, Tillage, And Fertility On Near-Surface Soil Carbon And Nitrogen Cycling, Jill Marie Motschenbacher Dec 2012

Long-Term Effects Of Rice Rotation, Tillage, And Fertility On Near-Surface Soil Carbon And Nitrogen Cycling, Jill Marie Motschenbacher

Graduate Theses and Dissertations

Rice (Oryza sativa L.)-based cropping systems are different from other row crops due to the flood-irrigation scheme used from about one month after planting to a few weeks prior to harvest. The frequent cycling between anaerobic (i.e., flooding during the growing season) and aerobic (i.e., generally, the remainder of the year) conditions can influence the rate of soil organic matter (SOM) decomposition, which can greatly influence carbon (C) and nitrogen (N) storage and sequestration in the soil over time. Therefore, a study was conducted on a silt-loam soil (fine, smectitic, thermic, Typic Albaqualf) at the Rice Research and Extension Center …


Expansion Of Human Induced Pluripotent Stem Cells On Synthetic Substrate In Defined Medium, Huantong Yao Dec 2012

Expansion Of Human Induced Pluripotent Stem Cells On Synthetic Substrate In Defined Medium, Huantong Yao

Graduate Theses and Dissertations

Human induced pluripotent stem cells (hiPSCs) have the potential to generate patient-specific cells to treat many incurable diseases by cell replacement therapy. However, so far the culture of hiPSCs depends greatly on feeder cells or Matrigel which has safety issues. Thus, chemically defined substrates that could provide niches necessary for cell attachment and proliferation are preferred for clinical application of hiPSCs. Recently, Corning Life Sciences has developed synthetic peptide-functionalized cell culture surface, referred to as Corning® Synthemax that support self-renewal and differentiation of human embryonic stem cell (hESC). In this work, we have collaborated with Corning to investigate the attachment, …


Urbanism In The Northern Levant During The 4th Millennium Bce, Rasha El-Endari Dec 2012

Urbanism In The Northern Levant During The 4th Millennium Bce, Rasha El-Endari

Graduate Theses and Dissertations

The development of urbanism in the Near East during the 4thmillennium BCE has been an important debate for decades and with recent scientific findings, a revival of this intellectual discussion has come about. Many archaeologists suggested that urban societies first emerged in southern Mesopotamia, and then expanded to the north and northwest. With recent excavations in northern Mesopotamia, significant evidence has come to light with the finding of monumental architecture and city walls dated to the beginning of the 4th millennium BCE, well before southern Mesopotamian urban expansion. These discoveries reflect important administrative systems and stratified sociopolitical structures within these …


Population Dynamics In Predynastic Upper Egypt: Paleodemography Of Cemetery Hk43 At Hierakonpolis, Ernest King Batey Iii Dec 2012

Population Dynamics In Predynastic Upper Egypt: Paleodemography Of Cemetery Hk43 At Hierakonpolis, Ernest King Batey Iii

Graduate Theses and Dissertations

The site of Hierakonpolis is considered to have played an important role in the development of the Egyptian state, which formed at end of the fourth millennium BC. Archaeological evidence suggests that, for the Middle and Late Predynastic periods (ca. 3900-3200 BC), Hierakonpolis may be characterized as having experienced the following: a growth in both settlement and population size, an increased reliance on cereal agriculture, development of craft specialization, and the presence of a Social hierarchy as interpreted from an observed increase in the differentiation of mortuary behavior. Historical data suggest that these Social and economic changes would have affected …


Characterization And Epidemiology Of Soybean Vein Necrosis Associated Virus, Jing Zhou Dec 2012

Characterization And Epidemiology Of Soybean Vein Necrosis Associated Virus, Jing Zhou

Graduate Theses and Dissertations

Soybean vein necrosis disease (SVND) is widespread in major soybean-producing areas in the U.S. The typical disease symptoms exhibit as vein clearing along the main vein, which turn into chlorosis or necrosis as season progresses. Double-stranded RNA isolation and shot gun cloning of symptomatic tissues revealed the presence of a new tospovirus, provisionally named as Soybean vein necrosis associated virus (SVNaV). The presence of the virus has been confirmed in 12 states: Arkansas, Illinois, Missouri, Kansas, Tennessee, Kentucky, Mississippi, Maryland, Delaware, Virginia and New York. Symptomatic samples collected from eight states (AR, IL, MO, MS, KS, TN, MD and DE), …


Taxonomy And Dna Barcoding In The Genus Manfreda (Salisb.) Asparagaceae, William David Ritchie Dec 2012

Taxonomy And Dna Barcoding In The Genus Manfreda (Salisb.) Asparagaceae, William David Ritchie

Graduate Theses and Dissertations

The genus Manfreda Salisb. of Asparagaceae is a genus of potential horticultural interest and is currently subject to breeding efforts at the University of Arkansas. A lack of taxonomic clarity however undermines the classification of potential inter - and intrageneric hybrids. The study aims to assess existing species delimitation within the genus Manfreda employing morphology while investigating the potential utility of Consortium for the Barcode of Life Plant (CBOL) DNA Barcodes for identification of specific taxa and an External Transcribed Spacer (ETS) - Internal Transcribed Spacer (ITS) DNA barcode for developed hybridized taxa.

Observation of 855 herbarium specimens facilitated phylogenetic …


Aesthetic Qualities Of Websites And Their Effects On Public Perceptions Of Agricultural Issues And Organizations, Chase Tyler Hundley Dec 2012

Aesthetic Qualities Of Websites And Their Effects On Public Perceptions Of Agricultural Issues And Organizations, Chase Tyler Hundley

Graduate Theses and Dissertations

This study sought to evaluate perceptions of agricultural issues and organizations based on how information is presented visually in websites. Researchers intended the results to be used to help the agricultural industry more effectively communicate information through better website design and increased persuasiveness. The study was conducted through the use of three focus group sessions as mapped out by Krueger (1998a, 1998b, 1998c) and Morgan (1998a, 1998b). The study used non-agriculture students purposively selected from a class in the University of Arkansas School of Human Environmental Sciences as participants in the study. The subject demographics closely resembled the primary demographics …


Evaluation Of The Recombination Efficiencies Of Flp Proteins, Linh Duy Nguyen Dec 2012

Evaluation Of The Recombination Efficiencies Of Flp Proteins, Linh Duy Nguyen

Graduate Theses and Dissertations

Site-specific recombination systems are powerful tools for genetic modification. They have been used to integrate a transgene into a pre-defined locus and to remove marker genes from a transgene locus. Two of the most widely used site-specific recombination systems in plants are the Cre/lox system from the bacteriophage P1 and the FLP/FRT system from the yeast Saccharomyces cerevisiae. The Cre/lox system is well-characterized and is the first choice in application of site-specific recombination system. However, some applications such as marker-free site-specific gene integration require the use of two recombination systems. In addition, the availability of alternative recombination systems can offer …


Timing Of Castration, With Or Without Analgesia, On Growth Performance, Hematology, And Behavior Of Beef Calves, April C. Brown Dec 2012

Timing Of Castration, With Or Without Analgesia, On Growth Performance, Hematology, And Behavior Of Beef Calves, April C. Brown

Graduate Theses and Dissertations

Angus-sired (n = 30) and Hereford-sired (n = 32) bull calves were assigned randomly to 1 of 4 treatments. Treatments were 1) surgical castration near birth, 2) oral administration of the analgesic meloxicam (1 mg/kg of body weight) followed by surgical castration near birth, 3) surgical castration at weaning, or 4) surgical castration at weaning with oral administration of the analgesic meloxicam (1 mg/kg of body weight). Data was recorded for behavior, hematology, and growth at birth and weaning. Calf standing and lying activity was monitored at both stages by recording x and y axis positions of a data logger …


Ideology In Popular Late Twentieth And Twenty-First Century Children's And Young Adult Literature And Film, Iris Grace Shepard Dec 2012

Ideology In Popular Late Twentieth And Twenty-First Century Children's And Young Adult Literature And Film, Iris Grace Shepard

Graduate Theses and Dissertations

Texts created for the consumption of children and young adults are not simple texts made for the sole purpose of entertaining young audiences. In fact, these texts are complicated, multi-faceted texts that function both in the creation and performance of childhood. Children's and young adult literature and film disseminated mainstream ideology about young people's place in society and attempt to enculturate young readers and viewers in regards to race, gender, age, and Social class. However, by helping young people interact critically with these texts, critical thinking skills as well as a passion for reading can be fostered. In addition, by …


Response Of Broiler Chickens To Variation In Dietary Nutrient Content, Sarah Diane Goodgame Dec 2012

Response Of Broiler Chickens To Variation In Dietary Nutrient Content, Sarah Diane Goodgame

Graduate Theses and Dissertations

Rising feed costs, environmental pollution concerns targeted at animal agriculture, a worldwide focus on sustainability and the never ending battle to improve production and efficiency within the poultry industry challenges nutritionists to focus on products to improve nutrient digestibility and decrease feed costs while at the same time maximizing performance. The research presented in this dissertation focuses on improving nutrient utilization of protein sources with protein liberating enzymes currently available commercially. The research also conducted addresses the addition of crystalline amino acids valine and isoleucine and their effect on improving efficiency of broilers.

The first research project compared the efficacy …


Community Structure And Ecological Specialization In Plant-Ant Interactions, Paola Barriga Dec 2012

Community Structure And Ecological Specialization In Plant-Ant Interactions, Paola Barriga

Graduate Theses and Dissertations

Positive associations among species have contributed to the maintenance of biodiversity. These interactions are typically studied in pairwise fashion where two interacting organisms are the focus. This dissertation uses network theory to analyze positive plant-ant associations in three Neotropical forests. Obligate plant-ant mutualisms were used, where plants host the ants in domatia and provide food bodies while the ants protect the plants and can feed them. A network approach was used to depict all obligate plant-ant interactions within a community. The main questions asked at the community level were: 1) Do network structure and levels of specialization change geographically and, …


Breeding For Modified Seed Composition In Soybean: Selection Of Genotypes, Yield Stability, And Environmental Effects, Luciano Miguel Jaureguy Dec 2012

Breeding For Modified Seed Composition In Soybean: Selection Of Genotypes, Yield Stability, And Environmental Effects, Luciano Miguel Jaureguy

Graduate Theses and Dissertations

The development of cultivars with modified seed composition represents an excellent alternative to cope with the world's need for more nutritious food. Understanding the genetic and environmental factors controlling crop seed quality traits is of crucial importance for such an endeavor. The objectives of this study were: a) to evaluate the efficiency of phenotype and marker-assisted selection for low stachyose and low phytate soybean breeding lines, and their yield stability, b) to study the effect of management practices planting date and delayed harvest on soybean seed composition, and c) to study the potential association between soil properties and leaf chemical …


Effects Of Felled Shortleaf Pine (Pinus Echinata Mill.) Moisture Loss On Oviposition Preferences And Survival Of Sirex Nigricornis F. (Hymenoptera: Siricidae), Jessica Hartshorn Dec 2012

Effects Of Felled Shortleaf Pine (Pinus Echinata Mill.) Moisture Loss On Oviposition Preferences And Survival Of Sirex Nigricornis F. (Hymenoptera: Siricidae), Jessica Hartshorn

Graduate Theses and Dissertations

The European woodwasp, Sirex noctilio F. (Hymenoptera: Siricidae) utilizes pine as its host during larval development. Females drill through pine bark to deposit eggs, a symbiotic fungus, Amylostereum, and phytotoxic mucus into the tree. In their native range, these insects are not viewed as primary pests because they attack dead or dying trees. Over the last century, this woodwasp has been accidentally introduced into several countries in the southern hemisphere. Some regions have incurred millions of dollars in damage to large plantations of the widely planted pine species, radiata pine (Pinus radiata D. Don). Sirex noctilio was discovered …


Influence Of Nutritional Modifications On Sow, Litter, And Nursery Performance, Benjamin Edward Bass Dec 2012

Influence Of Nutritional Modifications On Sow, Litter, And Nursery Performance, Benjamin Edward Bass

Graduate Theses and Dissertations

Two separate series of experiments were conducted to determine: 1) the influence of dietary arginine supplementation in late gestation on reproductive performance, and 2) the impact of a whole yeast product in gestation, lactation, and weaned pig diets on reproductive, growth, and immune parameters.

In the first study 99 sows were provided a control diet, or the control diet supplemented with 1% L-arginine from gestation d 93 to 110. Compared to control-fed sows, no differences were observed in reproductive parameters, however a tendency for increased gestational weight gain was observed for sows provided supplemental arginine.

In a second study, 98 …


Witch Hazel Advent, The Story Of An Ozark Poet, Sarah Moore Chyrchel Dec 2012

Witch Hazel Advent, The Story Of An Ozark Poet, Sarah Moore Chyrchel

Graduate Theses and Dissertations

The goal of this Master's thesis project was to document the life of my maternal step-grandfather, John Ross Rule, in a visually compelling manner. Using equipment provided by the Lemke Department of Journalism at the University of Arkansas, I shot and edited a half hour long documentary film comprised of interviews and footage of John at his home near Winslow, Arkansas. John is a talented poet, and segments of his poetry are woven throughout the film.

The inspiration for this project is deeply rooted in place: the remote farmstead in the Boston Mountains of northwestern Arkansas that my grandparents called …


The Impact Of Bovine Spongiform Encephalopathy (Bse) On World Protein Supply, Jarrod Kersey Dec 2012

The Impact Of Bovine Spongiform Encephalopathy (Bse) On World Protein Supply, Jarrod Kersey

Graduate Theses and Dissertations

As world population, per capita income and urbanization increase, consumption of meat, poultry, milk and eggs will continue to rise to meet the needs of approximately nine billion people in 2050. Global beef, pig and chicken production and per capita consumption increased between 2000 and 2010, with growth in broiler production and consumption outpacing both beef and swine. The increased production and consumption requires readily available feed ingredients in regions where animal production is rapidly developing. Animal-based protein feed ingredients are often difficult to move from country to country due to real or perceived risk of animal disease. Zoosanitary standards …


Effects Of Meloidogyne Incognita, Soil Physical Parameters, And Thielaviopsis Basicola On Cotton Root Architecture And Plant Growth, Jianbing Ma Aug 2012

Effects Of Meloidogyne Incognita, Soil Physical Parameters, And Thielaviopsis Basicola On Cotton Root Architecture And Plant Growth, Jianbing Ma

Graduate Theses and Dissertations

The root-knot nematode, Meloidogyne incognita, and the seedling pathogen, Thielaviopsis basicola, commonly co-exist in Arkansas cotton fields and may interact resulting in increased losses. The primary objective of this research was to evaluate the effects of soil physical parameters on these soilborne pathogens and cotton growth in controlled environmental, field, and microplot studies. Controlled environmental experiments used two soil bulk densities and four pathogen treatments: non-infested soil, soil infested with M. incognita or T. basicola and soil infested with both pathogens. The results indicated bulk density generally did not affect seedling growth or disease since soils had low penetration resistance …


Ant Tribe, Yan Zhao Aug 2012

Ant Tribe, Yan Zhao

Graduate Theses and Dissertations

"Ant Tribe" describes the post-80s generation university graduates who live together in poor conditions without Social security in communities around China's major metropolises. They dream of a better life in big cities but struggle with low-paying jobs. These struggling "elites" have become the fourth weak Social group, after peasants, migrant workers and unemployed people. The reason why these college graduates are compared to ants is that they are like ants: clever, hardworking, politically weak and living in groups.

The real world is always different from the ideal world of the "Ant Tribe" in China. They often lose their purposes in …


Effects Of Testing Time On Anaerobic Toxicity Assessment, Omolola Atinuke Akintomide Aug 2012

Effects Of Testing Time On Anaerobic Toxicity Assessment, Omolola Atinuke Akintomide

Graduate Theses and Dissertations

Anaerobic digestion has been widely used for wastewater treatment for decades. Several Anaerobic Toxicity tests have been developed to screen wastewater for toxicity and assess the treatability of such toxicants. However, past research and reviews on Biochemical Methane Potential (BMP) test and Anaerobic Toxicity Assay (ATA) were considered in this study.

The experimental tests included ammonium-nitrogen and sodium chloride toxicity tests with varied concentration and solid retention time. These tests were designed to demonstrate the impact of ammonia- nitrogen and sodium chloride on the biological degradation process. The anaerobic test set-up includes bench-scale test reactors and respirometers used for measuring …


The Identification Of Quantitative Trait Loci For Sucrose And Stachyose Content In Soybean Seed, Ailan Zeng Aug 2012

The Identification Of Quantitative Trait Loci For Sucrose And Stachyose Content In Soybean Seed, Ailan Zeng

Graduate Theses and Dissertations

Sucrose is a desirable sugar in soybean seed that affects the quality and taste of soyfoods, while stachyose is a non-digestible sugar that induces flatulence in non-ruminant animals. Therefore, soybean cultivars with high sucrose and/or low stachyose would be valuable for soyfood and meal markets. The objectives of this study were to identify quantitative trait loci (QTL) or genes associated with seed sucrose and stachyose content using simple sequence repeat (SSR) or single nucleotide polymorphism (SNP) markers. A low sucrose line, MFS-553, was crossed with a high sucrose plant introduction, PI 243545, to develop the sucrose QTL mapping population. A …


A Way Out: The History Of The Outing Program From The Haskell Institute To The Phoenix Indian School, Alexandria L. Gough Aug 2012

A Way Out: The History Of The Outing Program From The Haskell Institute To The Phoenix Indian School, Alexandria L. Gough

Graduate Theses and Dissertations

From the earliest years of the United States, its leaders wrestled with the perceived need to assimilate Indian peoples into American society. Many believed that Indians in their "natural" condition were cultural primitives incapable of taking part in national life. However, with proper guidance they could be elevated to a level of civilization that would allow them to join the national family. After the conclusion of the Indian Wars in the 1880's, the United States government began to address the continued "Indian" problem by establishing Indian boarding schools. Indian children attended school to learn to behave as white, Christian and …


Relationship Of Polymorphisms In The Fsh Beta Subunit Gene With Reproduction In Bos Taurus And Bos Indicus Cattle, Amanda Jo Davis Aug 2012

Relationship Of Polymorphisms In The Fsh Beta Subunit Gene With Reproduction In Bos Taurus And Bos Indicus Cattle, Amanda Jo Davis

Graduate Theses and Dissertations

Two experiments were conducted to characterize polymorphisms (SNP) in the bovine FSHβ gene promoter region to examine breed differences in SNP, and to determine effects of SNP on reproduction in beef cattle. Experiment 1 - DNA samples were collected from 5 Angus (ANG), 13 Balancer (BAL), & 16 Brahman influenced (BI) bulls. Polymorphisms were identified by sequencing of 3 sequential PCR products from the promoter region revealed 17 SNP & 4 insertion/deletions (INDEL). Semen samples were collected and sperm quality variables determined via computer assisted sperm analysis (CASA) or stained smears. The MIXED procedure for ANG & BAL indicated interactions …


Lactic Acid Production Using Sweet Potato Processing Waste, Irene Pagana Aug 2012

Lactic Acid Production Using Sweet Potato Processing Waste, Irene Pagana

Graduate Theses and Dissertations

Organic waste generated from industrial sweet potato canning is estimated to be 30% of incoming raw material. This waste contains carbohydrates (sugars and starch) that could be used as substrates for the production of useful compounds via fermentation (e.g. lactic acid), resulting in the production of value-added products. The goal of this research project is to produce a substrate from the sweet potato processing waste material that supports the growth of lactic acid bacteria, which results in the production of lactic acid. The sweet potato waste product was characterized, and found to contain 16.5% solids. The solids components were 18.5% …


Modes Of Presentation In The Education Of Secondary Students With Disabilities, Annie Laurie Quinn Aug 2012

Modes Of Presentation In The Education Of Secondary Students With Disabilities, Annie Laurie Quinn

Graduate Theses and Dissertations

Abstract: bold


Defending The Multiple Realization Argument Against The Identity Theory, David Barrett Aug 2012

Defending The Multiple Realization Argument Against The Identity Theory, David Barrett

Graduate Theses and Dissertations

A classic argument in the philosophy of mind is that the identity theory is false because mental state types are multiply realized in brain state types. In this dissertation I provide a detailed elaboration of the argument and a defense of it against a few of its prominent contemporary critics. Finally I offer empirical evidence from inter-species differences in humans and monkeys, and also from a case of extensive neural plasticity, which shows that mental state types are multiply realized in brain state types.


Motivational Inequality: Prevention Goals Induce More Effort Than Promotion Goals, Jennifer Marie Pattershall-Geide Aug 2012

Motivational Inequality: Prevention Goals Induce More Effort Than Promotion Goals, Jennifer Marie Pattershall-Geide

Graduate Theses and Dissertations

Regulatory focus theory describes two motivational strategies--promotion and prevention focus--that may be employed during goal directed action. Although a theory of motivation, there is no research examining differences in effort between promotion and prevention focus. Two studies are presented which test the hypothesis that goals pursued with a prevention focus, with its emphasis on duties, responsibilities, and avoidance of negative outcomes, will induce more effort than goals pursued with a promotion focus, which emphasizes hopes, ideals, and achieving positive outcomes. In addition, several potential mediators and moderators of this effect were examined. In Study 1, students who completed an essay …


The Ipad As An Instructional Tool: An Examination Of Teacher Implementation Experiences, Brandie Kay Benton Aug 2012

The Ipad As An Instructional Tool: An Examination Of Teacher Implementation Experiences, Brandie Kay Benton

Graduate Theses and Dissertations

At present, handheld devices and tablet computers are infiltrating public schools across the nation, the most popular model being the Apple iPad. Schools and teachers are attempting to integrate the devices and are using a variety of methods and models for implementation. The purpose of this study was to examine the implementation of the iPad as an instructional tool through the experiences of classroom teachers.A review of related literature was conducted to inform the conceptual framework, design, data collection, analysis, and synthesis components and stages of this study. Qualitative methods, including teacher-participant interviews and classroom observations, were utilized in this …


"It Was Awful, But It Was Politics": Crittenden County And The Demise Of African American Political Participation, Krista Michelle Jones Aug 2012

"It Was Awful, But It Was Politics": Crittenden County And The Demise Of African American Political Participation, Krista Michelle Jones

Graduate Theses and Dissertations

Despite the vast scholarship that exists discussing why Democrats sought restrictive suffrage laws, little attention has been given by historians to examine how concern over local government drove disfranchisement measures. This study examines how the authors of disfranchisement laws were influenced by what was happening in Crittenden County where African Americans, because of their numerical majority, wielded enough political power to determine election outcomes. In the years following the Civil War, African Americans established strong communities, educated themselves, secured independent institutions, and most importantly became active in politics. Because of their numerical majority, Crittenden's African Americans were elected to county …