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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 …


False Smut Of Rice: Histological Analysis Of Infection, Liem Thi Thanh Nguyen Dec 2012

False Smut Of Rice: Histological Analysis Of Infection, Liem Thi Thanh Nguyen

Graduate Theses and Dissertations

False smut of rice, caused by Ustilaginoidea virens (Cooke) Takahashi (Teleomorph: Villosiclava virens), has become a common disease in most major rice growing regions throughout the world. Considerable confusion exists regarding the infection process and the disease cycle. Therefore, a clearer understanding of pathogenesis caused by Ustilaginoidea virens is critical for future efforts to develop genetic and chemical tools to manage false smut in Arkansas and other regions of the world. The overall goal of this research was to clarify the infection process underlying false smut, with emphasis on comparing and contrasting the histological basis of root and foliar infections. …


On Export Intermodal Transportation Problem, Supriya Arun Jadhav Dec 2012

On Export Intermodal Transportation Problem, Supriya Arun Jadhav

Graduate Theses and Dissertations

This thesis investigates a logistics problem facing companies that export their products to other countries. The problem is called export intermodal transportation problem. In the export intermodal transportation problem, goods ordered by overseas customers need to be transported from production plants or warehouses of an export company to the customers destinations overseas. The transportation involves using multiple transportation modes such as trucks and rails for the inland portion and ocean liners for the overseas portion, and its objective is to have the goods moved and the cost minimized subject to various constraints. Cost can be minimized by combining orders from …


Mapping Xenophobic Violence In South Africa: Modeling Spatial Relationships Between Group Grievances And Opportunities To Measure The Propensity For Xenophobic Violence, Eric Holder Dec 2012

Mapping Xenophobic Violence In South Africa: Modeling Spatial Relationships Between Group Grievances And Opportunities To Measure The Propensity For Xenophobic Violence, Eric Holder

Graduate Theses and Dissertations

Xenophobia can be defined as the hatred or fear of foreigners or strangers or of their politics or culture (Ngwane et al., 2008). This sentiment reached its tipping point in urban areas across the Republic of South Africa in May 2008 when mass, widespread and systematic attacks against African non-nationals took place across the country. Although previous research agrees on who played the various roles during this crisis event (Everatt, 2010), little research has been carried out to create a predictive model to assess where future violence could occur based on a set of conflict indicators. The purpose of this …


Stress-Adaptation And Stress-Induced Changes In Campylobacter Jejuni, Geetha Sanal Kumar-Phillips Dec 2012

Stress-Adaptation And Stress-Induced Changes In Campylobacter Jejuni, Geetha Sanal Kumar-Phillips

Graduate Theses and Dissertations

The foodborne pathogen Campylobacter jejuni is one of the leading causes of human gastroenteritis. This bacterium is not a robust organism compared with many other foodborne pathogens and requires special conditions in the laboratory for its growth. In nature, however, this organism is able to survive in very diverse and hostile environments and produce disease in humans. The different mechanisms by which C. jejuni survives stressful conditions in the environment remain unclear. Adhesion and invasion are thought to be important factors for the colonization of C. jejuni in the intestinal tracts of hosts. Previous research in our laboratory showed that …


Energy And Spectral Efficient Wireless Communications, Guoqing Zhou Dec 2012

Energy And Spectral Efficient Wireless Communications, Guoqing Zhou

Graduate Theses and Dissertations

Energy and spectrum are two precious commodities for wireless communications. How to improve the energy and spectrum efficiency has become two critical issues for the designs of wireless communication systems. This dissertation is devoted to the development of energy and spectral efficient wireless communications. The developed techniques can be applied to a wide range of wireless communication systems, such as wireless sensor network (WSN) designed for structure health monitoring (SHM), medium access control (MAC) for multi-user systems, and cooperative spectrum sensing in cognitive radio systems.

First, to improve the energy efficiency in SHM WSN, a new ultra low power (ULP) …


What Is The Participant Learning Experience Like Using Youtube To Study A Foreign Language?, Yuan-Hsiang Lo Dec 2012

What Is The Participant Learning Experience Like Using Youtube To Study A Foreign Language?, Yuan-Hsiang Lo

Graduate Theses and Dissertations

This research is to explore and understand participants' experience using YouTube to learn a foreign language. YouTube and learning has become more and more popular in the recent years. The finding of this research will be adding more understanding to the emerging body of knowledge of YouTube phenomenon. In this research, there are three interviews and two questionnaires. The interviews are conducted to find in-depth responses from participants; the questionnaires are used to inquire demographic and basic information about the participants. There are twelve themes found in this research. These themes reflect on the perceived experience using YouTube to learn …


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 …


Preparedness To Implement Wellness Strategies: Perceptions Of School Counselors, Tena Burnett Dec 2012

Preparedness To Implement Wellness Strategies: Perceptions Of School Counselors, Tena Burnett

Graduate Theses and Dissertations

The purpose of this study is to survey school counselors to determine their knowledge and perceived preparedness to implement wellness strategies in school counseling programs. Wellness plans are a requirement for thousands of public school districts in the United States. There are no established standards for the training of school counselors in the area of wellness. School counselors are in a unique position to positively impact students through the use of wellness programs and strategies. School counselors from a mid-south state (N = 156) completed an electronic survey to measure how they implement wellness strategies and their perceived preparedness in …


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, …


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 …


Identifying Local Entrepreneurship Development System Policy In Rural Areas And How Local Context Shapes Entrepreneurship Policy Formation, Stacey Wright Mccullough Dec 2012

Identifying Local Entrepreneurship Development System Policy In Rural Areas And How Local Context Shapes Entrepreneurship Policy Formation, Stacey Wright Mccullough

Graduate Theses and Dissertations

As rural communities struggle to maintain a sustainable economic base in today's global economy, many are exploring strategies to encourage entrepreneurial development. The purpose of this study was to better understand how local public policy is being be used to support the creation of entrepreneurship development systems in rural communities and how local context shapes entrepreneurship public policy formation. In phase one of the study, a survey and analysis of documents available on the Internet were used to identify county and municipal policy actions associated with entrepreneurial development in 16 counties in North Carolina. In the second study phase, two …


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 …


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 …


An Ethnographic Case Study Of A Deaf Workforce Collective, Peter Shane Butler Dec 2012

An Ethnographic Case Study Of A Deaf Workforce Collective, Peter Shane Butler

Graduate Theses and Dissertations

This ethnographic study seeks to increase our understanding of the individual and shared experiences of five members of a Deaf United States Postal Service (USPS) collective employment cohort in regards to their early learning experiences, how these experiences led to collective employment, and how the collective employment opportunity led them to establish a new Strong Deaf Community in Houston. The data collected through semi structured interviews will be used to increase our understanding about how Strong Deaf Communities form, and what purpose they serve for grassroots members.

This study also seeks to shed light on why it is critical for …


Plasmonic And Photonic Designs For Light Trapping In Thin Film Solar Cells, Liming Ji Dec 2012

Plasmonic And Photonic Designs For Light Trapping In Thin Film Solar Cells, Liming Ji

Graduate Theses and Dissertations

Thin film solar cells are promising to realize cheap solar energy. Compared to conventional wafer cells, they can reduce the use of semiconductor material by 90%. The efficiency of thin film solar cells, however, is limited due to insufficient light absorption. Sufficient light absorption at the bandgap of semiconductor requires a light path more than 10x the thickness of the semiconductor. Advanced designs for light trapping are necessary for solar cells to absorb sufficient light within a limited volume of semiconductor. The goal is to convert the incident light into a trapped mode in the semiconductor layer.

In this dissertation, …


The Relationship Of Peer Acceptance, Age, Gender, Ethnicity, And Appearance Among Preschoolers, Kora Klaire Stuffelbeam Dec 2012

The Relationship Of Peer Acceptance, Age, Gender, Ethnicity, And Appearance Among Preschoolers, Kora Klaire Stuffelbeam

Graduate Theses and Dissertations

The purpose of this study was to examine preschool children's acceptance of peers. The term peer acceptance is defined as "the degree a child is Socially accepted or rejected by his or her peer group." Johnson et al. (2002) found children between the ages of three and five were able to develop friendships and Social skills that would impact their acceptance among peers. The study determined if children based their choice of peers according to a child's age, gender, ethnicity, appearance, and/or Social skills. The subjects of this study were 31 children whose ages were three-, four-, and five-years-old who …


Perceptions Of A Middle School Reconfiguration: A Descriptive Case Study, Karen Billingsley Lasker Dec 2012

Perceptions Of A Middle School Reconfiguration: A Descriptive Case Study, Karen Billingsley Lasker

Graduate Theses and Dissertations

The purpose of this qualitative research study was to follow 1 principal's journey to assist the district in its reconfiguration goals, and help the school change through deep examination of district personnel's and parents' perceptions of the change process. This was done by acknowledging distinctions and differences between junior high schools, the current middle school, and the new middle school, delineated by current middle school-reform research. This study explored issues regarding the policies, personnel, decision-making strategies, timelines, and organizational structures of the new middle school.

The reconfiguration resulted in rezoning attendance zones, reconstructing the new high school, raising the new …


Trait Differences In Gender In Technology Use And Study Habits Of Rural Community College Students, Phillip Marc Wilson Dec 2012

Trait Differences In Gender In Technology Use And Study Habits Of Rural Community College Students, Phillip Marc Wilson

Graduate Theses and Dissertations

The purpose for conducting the study was to explore the trait differences by gender of the study habits and technology use patterns of rural community college students. Significant research and data presently exists at the university level specific to study habits and technology use, but little research had been conducted targeting those topics in a rural community college setting.

The following questions guided the research:

1. What were the study habits of rural community college students?

2. How did rural community college students use technology?

3. Were there significant differences, by gender, in the study habits of rural community college …


Penetration Forces For Subsurface Regolith Probes, Ahmed Elshafie Dec 2012

Penetration Forces For Subsurface Regolith Probes, Ahmed Elshafie

Graduate Theses and Dissertations

Investigating planetary bodies using penetrometers can provide detailed information about its history and evolution. An estimation of subsurface density and porosity can be made from the shape of the penetration curve. Using penetrometers mounted on planetary platforms could be challenging due to the uncertainty of the subsurface composition and since the maximum allowed force for penetration is the weight of the lander or rover on the surface. Estimation of penetration forces can provide a reliable constraint on the maximum reachable depth without endangering the whole mission. Therefore, knowledge of the required penetration force to specific depths can be helpful in …


Capillary And Microchip Electrophoresis For The Monitoring Of Disease Causing Amyloid Proteins, Elizabeth Nancy Pryor Dec 2012

Capillary And Microchip Electrophoresis For The Monitoring Of Disease Causing Amyloid Proteins, Elizabeth Nancy Pryor

Graduate Theses and Dissertations

The detection of oligomers and aggregates formed by two amyloid proteins, insulin and amyloid-beta (AB), is of particular importance due to the role which these species play in Diabetes and Alzheimer's disease, respectively. However, existing techniques are limited in the ability to detect insulin and AB; oligomers due to the fact that these early aggregates are transient, present at low concentrations, and difficult to isolate. Improvements must be made to existing techniques or alternative techniques must be explored in order to identify and quantify the size of these oligomeric and aggregate species without disrupting their structure.

Capillary and microchip electrophoresis …


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 …


Modeling, Fabrication And Characterization Of Scalable Electroless Gold Plated Nanostructures For Enhanced Surface Plasmon Resonance, Gyoung Gug Jang Dec 2012

Modeling, Fabrication And Characterization Of Scalable Electroless Gold Plated Nanostructures For Enhanced Surface Plasmon Resonance, Gyoung Gug Jang

Graduate Theses and Dissertations

The scientific and industrial demand for controllable thin gold (Au) film and Au nanostructures is increasing in many fields including opto-electronics, photovoltaics, MEMS devices, diagnostics, bio-molecular sensors, spectro-/microscopic surfaces and probes. In this study, a novel continuous flow electroless (CF-EL) Au plating method is developed to fabricate uniform Au thin films in ambient condition. The enhanced local mass transfer rate and continuous deposition resulting from CF-EL plating improved physical uniformity of deposited Au films and thermally transformed nanoparticles (NPs). Au films and NPs exhibited improved optical photoluminescence (PL) and surface plasmon resonance (SPR), respectively, relative to batch immersion EL (BI-EL) …


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 …


Effects Of Environment And Genotype On Charcoal Rot Development On Soybeans, Micah Diane Doubledee Aug 2012

Effects Of Environment And Genotype On Charcoal Rot Development On Soybeans, Micah Diane Doubledee

Graduate Theses and Dissertations

Charcoal rot of soybean, caused by the soilborne fungus Macrophomina phaseolina (Tassi) Goid, is a disease associated with high soil temperature and low soil moisture. Above-ground symptoms, which can be difficult to distinguish from drought symptoms, include low vigor, dead leaves that remain attached to the plant, early senescence and yield loss. Irrigation limits damage, but does not prevent colonization of the tissue by the pathogen. No soybean line is immune to M. phaseolina, but a few lines may have moderate resistance. The objectives of this research were to 1) determine the effects of genotype and drought on the development …


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 …


The Development Of A High Performance Concrete To Store Thermal Energy For Concentrating Solar Power Plants, Emerson Esmond John Aug 2012

The Development Of A High Performance Concrete To Store Thermal Energy For Concentrating Solar Power Plants, Emerson Esmond John

Graduate Theses and Dissertations

In recent years, due to rising energy costs as well as an increased awareness of the environmental effects of greenhouse gas emissions produced through traditional forms of energy production, there is great interest in developing alternative sources of energy. One of the most viable alternative energy sources is solar energy. In particular, concentrating solar power (CSP) technologies have been identified as an option for meeting utility needs in the U.S. Southwest. These systems are required to produce electricity not only during periods of high solar radiation but also during times of reduced radiation due to cloud cover, and even extend …


Improved Protocols For Automated Wheelpath Crack Detection In Pavements, Daniel Patrick Byram Aug 2012

Improved Protocols For Automated Wheelpath Crack Detection In Pavements, Daniel Patrick Byram

Graduate Theses and Dissertations

Roadway pavement distress evaluations are vital to understanding the mechanics of pavement stability, determining the distribution of rehabilitation costs, and knowing the appropriate rehabilitation strategies. Advancements in technology over the past two decades have changed the way these surveys have been performed by means of automated data collection and interpretation. More and more state agencies have invested in automated road analyzing vehicles that are able to collect high resolution images of the pavement. Fewer have adopted automated data processing software with the ability to interpret road distresses due to the common discrepancies in distress classification algorithms.

In addition to automated …


Impact Of Hybrid Rice On Food Security: A Spatial Equilibrium Analysis Of Global Adoption And Diffusion Of Hybrid Rice Varieties, Till Ludwig Aug 2012

Impact Of Hybrid Rice On Food Security: A Spatial Equilibrium Analysis Of Global Adoption And Diffusion Of Hybrid Rice Varieties, Till Ludwig

Graduate Theses and Dissertations

Rice is the staple crop for most consumers in Asia. More than half of the global population depends on rice. However, scarce resources for agricultural production and unfavorable conditions will make it hard to meet future demand in rice and threaten future food security. Hybrid rice technology is a method to increase the productivity of resources needed for rice production. Current developments show not only yield improvements in comparison to existing conventional and hybrid varieties, but also fuel hopes for new abiotic and biotic stress tolerance. The objective of this study is to determine what impact hybrid rice varieties can …