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2009

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Investigation Of The Mechanical Properties Of Poly (Ethylene Glycol) Diacrylate By Nanoindentation Using Atomic Force Microscopy, Zouheir Drira Dec 2009

Investigation Of The Mechanical Properties Of Poly (Ethylene Glycol) Diacrylate By Nanoindentation Using Atomic Force Microscopy, Zouheir Drira

Theses and Dissertations

Poly (ethylene glycol) (PEG) hydrogel based polymers are among the most widely used synthetic materials for biomedical applications. Because of their biocompatibility, and ease of fabrication, hydrogels are highly suitable for use as constructs to engineer tissues as well as for cell transplantation. A critical parameter of importance for PEG hydrogels is their mechanical properties which are highly dependent on the environmental conditions. Properties of PEG-based hydrogels can be engineered to resemble scaffolds composed of extracellular matrix molecules, which provide structural support, adhesive sites and mechanical as well as biomechanical signals to most cells. The mechanical properties of these synthetic …

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The Effects Of Functional Behavior Assessment Teacher Training And Performance Feedback: Knowledge, Accuracy, And Acceptability And Their Ability To Accurately Complete Fba Procedures, Laquanta Watson Stewart Dec 2009

The Effects Of Functional Behavior Assessment Teacher Training And Performance Feedback: Knowledge, Accuracy, And Acceptability And Their Ability To Accurately Complete Fba Procedures, Laquanta Watson Stewart

Theses and Dissertations

Functional behavior assessment refers to the broad range of behavioral assessment methods used to identify or clarify the purpose or maintaining contingencies of problem behavior in order to design and implement function-based interventions designed to reduce the occurrence of the problem behavior and teach appropriate replacement skills. FBAs are required in the educational setting for students whose problem behavior is displayed to such a significant level that their learning or the learning of their peers is impacted. As such, previous researchers have conducted trainings on FBA for school-based personnel using a wide variety of methods. Unfortunately, the findings of these …

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Social Networking Systems Success Model: Assessment And Validation Of The Is Success Model In Social Context, Aaron Michael French Dec 2009

Social Networking Systems Success Model: Assessment And Validation Of The Is Success Model In Social Context, Aaron Michael French

Theses and Dissertations

Developments such as the ubiquity of electronic networks and the breadth of digital platforms beyond simple forums have lead to major economic and social transformations worldwide (Agarwal et al, 2008). This research will explore developments in the area of social networking using Internet technology in order to determine factors that lead to success. Despite considerable growth among the number of online communities available, very few are successful at retaining members and continued usage by its members (Ma & Agarwal, 2007). The purpose of this dissertation is to determine factors leading to a successful social networking site (SNS). Through the unification …

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Nutrient Management In On-Site Wastewater Treatment, Ayanangshu Dey Dec 2009

Nutrient Management In On-Site Wastewater Treatment, Ayanangshu Dey

Theses and Dissertations

Groundwater and surface water contamination has been linked in the past to inadequate or failing on-site wastewater treatment and disposal systems. The on-site wastewater systems installed in coastal areas have more potential for inflicting this kind of environmental damage. This work studied the regulatory compliance and environmental protection of the four types of on-site wastewater disposal systems found on the Mississippi Gulf Coast; i.e., vegetative rock filter, subsurface drip irrigation, sand mound, and sprinkler systems, by statistical techniques. Compliance was also evaluated for groundwater samples collected from monitoring wells installed at four corners of a disposal field. This work eventually …

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Laser Induced Incandescence And Laser Induced Breakdown Spectroscopy Based Sensor Development, Kemal Efe Eseller Dec 2009

Laser Induced Incandescence And Laser Induced Breakdown Spectroscopy Based Sensor Development, Kemal Efe Eseller

Theses and Dissertations

In this doctoral dissertation, two laser-based sensors were evaluated for different applications. Laser Induced Incandescence (LII) is a technique which can provide nonintrusive quantitative measurement of soot and it provides a unique diagnostic tool to characterize engine performance. Since LII is linearly proportional to the soot volume fraction, it can provide in situ, real time measurement of soot volume fraction with high temporal and spatial resolution. LII has the capability to characterize soot formation during combustion. The soot volume fraction from both flames and a soot generator was investigated with LII. The effects of experimental parameters, such as laser fluence, …

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Advancements In Power System Monitoring And Inter-Operability, Vinoth Mohan Mohan Dec 2009

Advancements In Power System Monitoring And Inter-Operability, Vinoth Mohan Mohan

Theses and Dissertations

In a typical utility control center, there could be hundreds of applications running to take care of day-to-day functionality. In many cases, these applications are custom-built by different vendors. With the expectation for high reliability of the electric power grid, many utilities are increasingly moving towards sharing data with each other and with security coordinators. But this data exchange is hampered by incompatible electrical applications built on proprietary data formats and file systems. Electric Power Research Institute's (EPRI‟s) Common Information Model (CIM) was envisioned as a one-sizeits-all data model to remove incompatibility between applications. This research work utilizes the CIM …

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Visual Perception And Gestalt Grouping In The Landscape: Are Gestalt Grouping Principles Reliable Indicators Of Visual Preference?, Mark Reinhardt Levy Dec 2009

Visual Perception And Gestalt Grouping In The Landscape: Are Gestalt Grouping Principles Reliable Indicators Of Visual Preference?, Mark Reinhardt Levy

Theses and Dissertations

Landscape visual preference research has indicated many potential indicators of preference; however a comprehensive framework concerning the relationship between visual preference and perception has not been solidified. Gestalt psychology, the predecessor to visual perception, proposes certain visual grouping tendencies to explain how humans perceive the world. This study examines if Gestalt grouping principles are reliable indicators of preference, and if they may be used to develop a broad context for visual assessment. Visual preference for 36 landscape scenes testing the proximity and similarity of landscape elements were ranked one through five by 1,749 Mississippi State University undergraduate, graduate, and faculty …

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Incentives For Poultry Integrators To Contract Bio-Secure Producers And Implication For Government Indemnification Program, Yichen Zhang Dec 2009

Incentives For Poultry Integrators To Contract Bio-Secure Producers And Implication For Government Indemnification Program, Yichen Zhang

Theses and Dissertations

These recent events of H1N1 flu outbreak illustrate the potential ramifications of infectious diseases on modern society and how society responds to these threats. This thesis addresses the specific case of avian influenza in U.S. poultry production. By building an expected utility maximization model for integrators contracting with growers of varying bio-secure levels, one can investigate the relationship between the bio-secure choice of the poultry industry and their production performance. The model is empiricized using the Phoon, Quek, and Huang (PQH) simulation technique to conduct numerical analysis. The model selects the optimal percentage of bio-secure farms for the integrators to …

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Flathead Catfish Stock Characteristics In The Pascagoula River Following Hurricane Katrina, Russell M. Barabe Dec 2009

Flathead Catfish Stock Characteristics In The Pascagoula River Following Hurricane Katrina, Russell M. Barabe

Theses and Dissertations

Flathead catfish stocks in the Pascagoula River were decimated by the passage of Hurricane Katrina. Age-0 fish survived the storm, producing a strong 2005 year-class. Reproduction by the remaining adults and/or downstream movement from tributaries produced an additional strong cohort in 2006. The strong 2005 year-class resulted in the capture of a high proportion of two-year-old fish in 2007. In 2008, a high proportion of two- and three-year-old fish were captured, illustrating the high rate of survival of the 2005 year-class, and the presence of a strong 2006 year-class. The flathead catfish population of the Pascagoula River was dominated by …

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Fractionation Of Soybean Meal, Cottonseed Meal And Wheat Middlings Using Combination Of Sieving And Air Classification, Ravi Kumar Challa Dec 2009

Fractionation Of Soybean Meal, Cottonseed Meal And Wheat Middlings Using Combination Of Sieving And Air Classification, Ravi Kumar Challa

Theses and Dissertations

Fiber separation from these animal feeds could increase the protein and hence increase the value of the animal feed. The objective of the study was to evaluate the combination of sieving and air classification for fiber separation from soybean meal (SBM), cottonseed meal (CSM) and wheat middlings (WM). The effect of yields of lighter fractions on fiber separation from size fractions was also investigated. At low yields of lighter fraction (5%), the quantity of fiber product separated was 3.7, 1.3 and 4.8% by weight of SBM, CSM and WM respectively. At high yields of lighter fractions (15%), the quantity of …

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Implementation And Impact Of A School-Based Intervention Program To Combat Obesity And Cardiovascular Disease In A Predominantly African-American High School, Brenda White Campbell Jenkins Dec 2009

Implementation And Impact Of A School-Based Intervention Program To Combat Obesity And Cardiovascular Disease In A Predominantly African-American High School, Brenda White Campbell Jenkins

Theses and Dissertations

This study addressed obesity of youth in a predominantly African-American school and was concerned with the implementation of a CVD intervention program, Project Health Curriculum, for high school students, focusing on early health promotion and support to children at risk of developing adult diseases. A health promotion program was implemented at a high school in Canton, Mississippi, to equip students with information to help reduce risk behaviors that could lead to health problems. This intervention was conducted in the health and physical education classes. Students were given the opportunity to report their knowledge and behaviors by participating in a pretest. …

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A Partial Discharge Measurement Technique For Applied Square Pulse Voltage With 50 Ns Rise Times, Clayborne Dudley Taylor Dec 2009

A Partial Discharge Measurement Technique For Applied Square Pulse Voltage With 50 Ns Rise Times, Clayborne Dudley Taylor

Theses and Dissertations

During the fabrication of solid electrical insulation, small cavities known as micro voids may form in the material. As electrical stress increases in this micro void, the breakdown probability also increases. This type of electrical breakdown is commonly known as partial discharge. Magnitudes of partial discharge currents are typically small but enough to cause degradation of the electrical insulation. To study degradation for fast-rise time voltage square pulse train, partial discharge measurement is needed. In current studies, partial discharge pulse widths have been measured in the range of nanoseconds. The best approach for measurement at ultra wide band frequencies is …

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An Analysis Of The Harvesting Costs And Productivity Of Logging Contractors Within The Eastern United States, Jeffrey Jaudon Smith Dec 2009

An Analysis Of The Harvesting Costs And Productivity Of Logging Contractors Within The Eastern United States, Jeffrey Jaudon Smith

Theses and Dissertations

A data set was compiled from detailed information provided from 26 independent logging contractors from throughout the Eastern United States over a five year period from 2000 to 2004. The age distribution of the logging contractors in the study has increased over time with the percentage of contactors over the age of 55 rising from 15% to 32%. The median age of all equipment including feller-bunchers, skidders, loaders, bulldozers, service vehicles, and haul trucks increased over the period. While the median age of all equipment increased, the age of service and support equipment saw the greatest increase. The total average …

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An Ecological Examination Of Dropout Rates And Multiple Level Measures Of Social Integration In Mississippi School Districts 2005-2008: Does Career And Technical Education Play A Part?, Jacob Travis Walker Dec 2009

An Ecological Examination Of Dropout Rates And Multiple Level Measures Of Social Integration In Mississippi School Districts 2005-2008: Does Career And Technical Education Play A Part?, Jacob Travis Walker

Theses and Dissertations

The purpose of this study was to conduct an ecological examination of the relationship between social integration and dropout rates at the school and community level, and the role of career and technical education in this relationship. This paper also attempts to determine if this relationship changes depending on how urbanicity is operationalized. This study adds to the existing research concerning the ecological relationships between dropout rates, community social integration, school social integration, and urbanicity in Mississippi. Three-year averaged event dropout rates for 2005-2008, multiple community and school measures of social integration, and three different operationalizations of urbanicity were used. …

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An Examination Of Crisis Preparedness At Christian-Affiliated Institutions Of Higher Education, Stacy M. Burrell Dec 2009

An Examination Of Crisis Preparedness At Christian-Affiliated Institutions Of Higher Education, Stacy M. Burrell

Theses and Dissertations

The purpose of this study was to examine crisis preparedness at Christian-affiliated institutions of higher education. Second, this study examined Christian-affiliated institutions of higher education presidents’ perspective of their institution’s ability to prepare for crises based upon the four critical indicators of organizational crisis preparedness as described by Zdziarski (2001): a) the types of crisis institutions prepare for, b) the phase of crisis prepared for, c) the systems in place to respond to crisis, and d) the stakeholders involved and considered in preparations. Implications from this study provided recommendations for crisis preparedness that are specific to Christian-affiliated colleges and universities. …

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The Role Of Cattle And Gulf Coast Ticks (Amblyomma Maculatum) In The Epidemiology Of Rickettsia Parkeri Infection, Kristine T. Edwards Dec 2009

The Role Of Cattle And Gulf Coast Ticks (Amblyomma Maculatum) In The Epidemiology Of Rickettsia Parkeri Infection, Kristine T. Edwards

Theses and Dissertations

I hypothesized cattle and Gulf Coast ticks (GCT), Amblyomma maculatum, may be involved in epidemiology of Rickettsia parkeri infection. I demonstrated transient rickettsemia by polymerase chain reaction (PCR) for the 17 kilodalton (kDa) gene in 33% (2/6) of calves experimentally exposed to R. parkeri either by direct inoculation or by placement of R. parkeri-infected GCT on calves’ ears. Calves (4/4) receiving GCT developed lesions at attachment sites consistent with a pathologic condition known as “gotch” ear whether or not GCT were infected with R. parkeri, suggesting the condition is related to GCT attachment and not to rickettsial infection. In calves …

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The Spatial Distribution Of Cn Radicals In The Coma Of Comet Encke, Chandrasiri Albert Ihalawela Dec 2009

The Spatial Distribution Of Cn Radicals In The Coma Of Comet Encke, Chandrasiri Albert Ihalawela

Theses and Dissertations

Comets are important for solar system studies because their interiors hold evidence of the conditions in which they formed in the outer solar system. However, the coma obscures the nucleus from view when observations are most easily performed, thus it is important to understand the nature of cometary comae. This study examines the spatial distribution of CN radicals in the coma of comet Encke and determines the likelihood that CN is a photodissociative daughter of HCN in the coma. Observations of CN were obtained from October 22-24, 2003, using the 2.7 m Cassegrain telescope at McDonald Observatory in Fort Davis, …

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Biomass Pretreatment For Increased Anhydrosugars Yield During Fast Pyrolysis, Qi Li Dec 2009

Biomass Pretreatment For Increased Anhydrosugars Yield During Fast Pyrolysis, Qi Li

Theses and Dissertations

Production of liquid fuels is a high national priority to provide transporation fuels. Production of liquid biouels from biomass has been idenfied as a viable goal over the next decades. Fast pyrolysis is the rapid thermal degradation of lignocellulosic biomass in the absence of oxygen. Levoglucosan, which can be hydrolyzed and fermented into bio-ethanol, is produced during the pyrolysis process of the cellulose contained in biomass. Pure cellulose results in the production of levoglucosan of more than 50% by feedstock weight while woody biomass typically produces about 3% during pyrolysis. Researchers have performed significant research into methods to increase yields …

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Career Paths, Barriers, And Professional Experiences: A Comparison Study Of African American Community College Presidents And White Community College Presidents, Cedric Andreas Bradley Dec 2009

Career Paths, Barriers, And Professional Experiences: A Comparison Study Of African American Community College Presidents And White Community College Presidents, Cedric Andreas Bradley

Theses and Dissertations

The community college is one of the most diverse institutions of higher learning in regards to the make-up of its student population. However, with such a large representation of diversity within its student population, the community college has not been as successful in diversifying the community college presidency. The purpose of this research study was to examine the career paths, barriers, and professional experiences of African American community college presidents and White community college presidents. A secondary purpose of this study was to examine potential recruitment strategies to recruit minority administrators. A total of 176 African American and White community …

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Effects Of Various Fumigants And Alternative Processing Methods On The Safety, Volatile Composition, And Sensory Quality Of Dry Cured Ham, Ramandeep Kaur Sekhon Dec 2009

Effects Of Various Fumigants And Alternative Processing Methods On The Safety, Volatile Composition, And Sensory Quality Of Dry Cured Ham, Ramandeep Kaur Sekhon

Theses and Dissertations

Randomized complete block designs with three replications were utilized to evaluate the effects of fumigation with sulfuryl fluoride (SF) (0, 12, 24, 36 and 72 mg/L), phosphine (PH3) (0, 200 and 1000 ppm at 48 hr), methyl bromide (MB) (0, 4, 8, 16, and 32 mg/L for 48 hr), carbon dioxide (CO2) (0, 60% at 48 hr and 60% at 96 hr) and ozone (O3) (0 ppm and 175 ppm for 48 hr) on the volatile flavor compound concentrations in dry cured ham. Fluoride and SF concentrations increased (P < 0.05) in dry cured hams as SF fumigation concentration increased, but all samples contained fluoride and SF concentrations below the legal limits of 20 and 0.01 ppm, respectively. Also, as phosphine fumigation concentration increased, the residual concentration of phosphine also increased in the hams (P < 0.05), but all samples contained levels that were lower than the legal limit of phosphine in stored food products (0.01 ppm). Minimal differences existed in the presence and concentration of aroma active compounds in fumigated hams when compared to the control. Triangle tests indicated that consumers could not discern (P > 0.75) between the control hams and the fumigated hams. This study …

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A Cross Cultural Validation Of Perceptions And Use Of Social Network Service: An Exploratory Study, Chengqi Guo Dec 2009

A Cross Cultural Validation Of Perceptions And Use Of Social Network Service: An Exploratory Study, Chengqi Guo

Theses and Dissertations

The rapid developments Social Network Service (SNS) have offered opportunities to re-visit many seminal theoretical assumptions of technology usage within socio-technical environment. Online social network is a rapidly growing field that imposes new questions to the existing IS research paradigm. It is argued that information systems research must necessarily evolve in response to the emerging trends (Lyytinen and King, 2004). Specifically, one stream of research has been heavily lacking is SNS usage prediction (Hargittai, 2007). In SNS, the form of social network is realized by computing networks where the individual assumes an identity of an “avatar”. People are merging their …

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A Descriptive Study Of Intercollegiate Athletics In Mississippi's Public Community And Junior Colleges, Brian Colson Alexander Dec 2009

A Descriptive Study Of Intercollegiate Athletics In Mississippi's Public Community And Junior Colleges, Brian Colson Alexander

Theses and Dissertations

The purpose of the study was to provide an assessment of the involvement of Mississippi's community and junior colleges in intercollegiate athletics during the academic year 2007–2008. These data could assist community and junior college presidents, vice presidents residing over athletics, athletic directors, and other policy makers in their decision-making processes concerning intercollegiate athletics. They could compare their institution with other institutions in the state. This study included the entire population of Mississippi's public community and junior colleges that offered intercollegiate athletics. Frequencies and percentages were utilized by the researcher to report the information. Data were collected to provide an …

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Current Sharing To Minimize Power Losses In Parallel Converters Using Pso, Dan Li Dec 2009

Current Sharing To Minimize Power Losses In Parallel Converters Using Pso, Dan Li

Theses and Dissertations

The Power Electronic Building Block (PEBB) concept leads to multifunctional converter systems, which provide robustness and flexibility in heavily power electronics based power systems. Systems comprised of flexible modular converters may have multiple possible operation conditions with respect to individual converters that meet the overall system goals. In this thesis, an optimization method for such flexible online power electronic systems is developed to minimize power losses of the overall group of converters in the system. Here the objective is to allocate sharing such that compensation objectives are met while the power loss of the entire parallel group of compensators is …

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Determining South Mississippi Forest Susceptibility To Windthrow And Shear Damage In A Hurricane Environment Through Data Mining Of Meteorological, Physiographical, Pedological, And Tree Level Data, Jared Seth Allen Dec 2009

Determining South Mississippi Forest Susceptibility To Windthrow And Shear Damage In A Hurricane Environment Through Data Mining Of Meteorological, Physiographical, Pedological, And Tree Level Data, Jared Seth Allen

Theses and Dissertations

An estimated 39 million m3 of timber was damaged across the Southeast Forest District of Mississippi due to Hurricane Katrina. Aggregated forest plot-level biometrics was coupled with wind, topographical, and soil attributes using a GIS. Data mining through Regression Tree Analysis (RTA) was used to determine factors contributing to shear damage of pines and wind-throw damage of hardwoods. Results depict Lorey’s Mean Height (LMH) and Quadratic Mean Diameter (QMD) are important variables in determining the percentage of trees and basal area damaged for both forest classes with sustained wind speed important for wind-throw and peak wind gusts for shear. Logistic …

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Do The Design Principles Established By William Hollingsworth Whyte For Creating Successful Urban Parks Apply To Parks In The New Urbanism Community Of Mt. Laurel?, William Miller Allen Dec 2009

Do The Design Principles Established By William Hollingsworth Whyte For Creating Successful Urban Parks Apply To Parks In The New Urbanism Community Of Mt. Laurel?, William Miller Allen

Theses and Dissertations

This thesis will study the resident’s perceptions of a community park in the new urbanism community of Mt Laurel, Alabama by evaluating the thirteen principles established by William Hollingsworth Whyte for creating successful urban parks. The thirteen principles established by Whyte for creating successful spaces are: •The parks proximity/relationship to the street •Location of the sidewalks to the street •Its ability to consistently sustain a constant flow of people through its boundaries •Its amount of defined spaces rather than large open spaces •Its amount of sitable space, in terms of ledges, steps, planters, chairs etc. •The parks sense of security …

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Effectiveness Of A Time Out From Reinforcement Package For Escape-Maintained Behaviors Exhibited By Typically Developing Children In Head Start, Melissa Marie Harber Dec 2009

Effectiveness Of A Time Out From Reinforcement Package For Escape-Maintained Behaviors Exhibited By Typically Developing Children In Head Start, Melissa Marie Harber

Theses and Dissertations

This investigation identified children whose noncompliant behavior was maintained by negative reinforcement through brief functional analysis conditions and then evaluated the effectiveness of a contraindicated treatment (i.e., time-out package) for decreasing the noncompliant behavior to developmentally appropriate levels. The current results provided initial supporting data that time-out, in conjunction with other treatment variables, can be an effective strategy in reducing escape maintained noncompliance. Brief experimental analysis conditions consistent with the methodology demonstrated by Northup and colleagues (1991), were utilized to identify escape as the maintaining variable for noncompliance. Following identification of the function of the behavior, baseline data were collected. …

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Improving Structural And Functional Annotation Of The Chicken Genome, Teresia Buza Dec 2009

Improving Structural And Functional Annotation Of The Chicken Genome, Teresia Buza

Theses and Dissertations

Chicken is an important non-mammalian vertebrate model organism for biomedical research, especially for vaccine production and the study of embryology and development. Chicken is also an important agricultural species and major food source for high-quality protein worldwide. In addition, chicken is an important model organism for comparative and evolution genomics. Exploitation of this genome as a biomedical model is hindered by its incomplete structural and functional annotation. This incomplete annotation makes it difficult for researchers to model their functional genomics datasets. Improving structural and functional annotation of the chicken genome will allow researchers to derive biological meaning from their functional …

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Inequality And Body Mass In Young Adulthood: Sex And Age Differences In Associated Effects, Jamie Lynn Boydstun Dec 2009

Inequality And Body Mass In Young Adulthood: Sex And Age Differences In Associated Effects, Jamie Lynn Boydstun

Theses and Dissertations

Approximately 63 percent of the U.S. adults are overweight or obese, however all groups are not affected equally. Little research has observed the obese compared to the overweight. This study aims to examine how measures associated with health differentially influence overweight and obesity. Data from the 2007 BRFSS were analyzed using logistic regression to assess variations due to socioeconomic, demographic, and health risk measures on overweight and obesity. Variations were assessed by age groups and sex. Differences across the subgroups were tested. The results showed that associated effects of overweight and obesity for young adults differ little from those of …

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Perceptions Of Motivation And Job Satisfaction For Information Technology Professionals At Institutions Of Higher Learning In Mississippi, Leann Mills Markham Dec 2009

Perceptions Of Motivation And Job Satisfaction For Information Technology Professionals At Institutions Of Higher Learning In Mississippi, Leann Mills Markham

Theses and Dissertations

Information technology is an ever evolving field that has become a mainstay in today’s society, especially in higher education. The employees who maintain the information technology (IT) infrastructure and systems at educational institutions are tasked with similar jobs as their equivalents in the private sector; however, these employees are faced with unique difficulties. A lower salary range, less benefits, and less technological variety are typical characteristics in a higher education setting for IT employees as compared to private industry. Faced with these circumstances, IT employees continue to perform their duties and ensure the institution is functioning on a daily basis. …

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Finite Element Modeling Of Plasticity Induced Crack Closure And A Mechanics Based Study Of Crack Closure Measurement Techniques, Marcos Lugo Dec 2009

Finite Element Modeling Of Plasticity Induced Crack Closure And A Mechanics Based Study Of Crack Closure Measurement Techniques, Marcos Lugo

Theses and Dissertations

From its discovery, crack closure was recognized as a key aspect in understanding the fatigue crack growth process. Considering the condition of plane stress, a vast amount of research has been conducted experimentally, analytically, and numerically to understand the complex process of fatigue crack growth and crack closure. Nonzero crack opening stress values are routinely observed, and it seems that there is a general agreement regarding the incidence of the phenomenon under plane stress. However, investigations regarding crack closure under plane strain conditions are less abundant. Moreover, the existence of crack closure under the plane strain state of the stress …

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