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Theses and Dissertations

Theses/Dissertations

2006

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Field Emergence Of Horseweed [Conyza Canadensis (L.) Cronq.] And Control Utilizing Tillage And Herbicides, Thomas William Eubank Dec 2006

Field Emergence Of Horseweed [Conyza Canadensis (L.) Cronq.] And Control Utilizing Tillage And Herbicides, Thomas William Eubank

Theses and Dissertations

Horseweed has been documented in 70 countries and 40 different crops around the world and is listed as being a problem weed in no-till production systems. Horseweed has developed resistance to many herbicide modes of action including glycine. Field experiments were conducted from 2004 to 2006 in the Mississippi Delta to evaluate the field emergence of horseweed and most effective treatment programs for its control. Field emergence of horseweed was observed occurring primarily in the fall of the year, September through early November, when temperatures were between 15.6 to 23.4 C with later flushes occurring from late January through early …

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French And Spanish In Contact: Code-Switching Among Spanish Immigrants In France, Anna Michalina Debicka-Dyer Dec 2006

French And Spanish In Contact: Code-Switching Among Spanish Immigrants In France, Anna Michalina Debicka-Dyer

Theses and Dissertations

This sociolinguistic study of the bilingual speech of Spanish immigrants in Toulouse, France focuses on the phenomenon of code-switching (CS). The analysis of the data showed that most CS was situational, rather than metaphorical. Three types of CS were found: insertion, alternation, and congruent lexicalization. Their examination revealed that the insertion of French words was more common than of Spanish items, the alternation was most frequent in repetitions, and the congruent lexicalization was present at the grammatical and structural level. The speech of the individual participants was also analyzed, and it was found that the sociological aspects greatly affected the …

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Development And Validation Of A Control Strategy For A Parallel Hybrid (Diesel-Electric) Powertrain, Jimmy C. Mathews Dec 2006

Development And Validation Of A Control Strategy For A Parallel Hybrid (Diesel-Electric) Powertrain, Jimmy C. Mathews

Theses and Dissertations

The rise in overall powertrain complexity and the stringent performance requirements of a hybrid electric vehicle (HEV) have elevated the role of its powertrain control strategy to considerable importance. Iterative modeling and simulation form an integral part of the control strategy design process and industry engineers rely on proprietary ?legacy? models to rapidly develop and implement control strategies. However, others must initiate new algorithms and models in order to develop production-capable control systems. This thesis demonstrates the development and validation of a charge-sustaining control algorithm for a through-the-road (TTR) parallel hybrid (diesel-electric) powertrain. Some unique approaches used in powertrain-level control …

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Body Mass Index And Percent Body Fat As Determined By Bioelectrical Impedance Analysis In Children, 7-9 Years Of Age, Patrick Alan Grady Dec 2006

Body Mass Index And Percent Body Fat As Determined By Bioelectrical Impedance Analysis In Children, 7-9 Years Of Age, Patrick Alan Grady

Theses and Dissertations

The purpose of this study was to examine the prevalence of overweight and report mean Body Mass Index (BMI) and percent body fat (%BF) in Black and non-Black children, 7-9 years of age. The study involved 172 students divided as follows: 56 (32.6%) Black females, 45 (26.2%) Black males, 34 (19.7%) non-Black females, and 37 (21.5%) non-Black males. Percent body fat (%BF) was determined by bioelectrical impedance analysis (BIA). Body mass index was calculated as weight (kg)/height (m)². Black females had a statistically greater BMI (19.3 ± 4.8) and %BF (25.7 ± 10.6) than all other groups. Prevalence of at-riskor-overweight …

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Effectiveness Of Postharvest Sanitation Treatments On Microbial Load Of Blueberries, Wei-Chun Chen Dec 2006

Effectiveness Of Postharvest Sanitation Treatments On Microbial Load Of Blueberries, Wei-Chun Chen

Theses and Dissertations

The purpose of this study was to determine the quality and microbial load of blueberries at different maturity stages, to develop the effective microbial recovery method and to compare sanitation postharvest treatments on microbial counts of blueberries. The soluble solids and the sugar to acid ratio increased, while pH and TA decreased with maturity. Ripe berries had lower yeast and mold counts (YMC) at other maturity stages, but there were no differences on aerobic plate counts (APC). The medium pH was lower for stomaching and blending than hand massaged samples. This leads to higher recovery of microorganisms by massaging. Sodium …

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A Bandwidth Estimation Method For Ip Version 6 Networks, Marshall Crocker Dec 2006

A Bandwidth Estimation Method For Ip Version 6 Networks, Marshall Crocker

Theses and Dissertations

Efficiently and accurately estimating bandwidths in packet networks is a problem that has intrigued researchers for years. There is no simple manner for estimating bandwidths in IPv4 networks that is accurate, efficient, flexible, and suitable for a variety of applications. Many of the available estimation techniques suffer from inherent flaws such as inaccuracy due to simple assumptions about the network or an overall high complexity that makes it inappropriate in all but a few highly specific situations. The next generation Internet Protocol, IP version 6, has the functionality necessary to implement feedback mechanisms to assist in accurate bandwidth estimations. This …

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Heat Transfer And Friction In Helically-Finned Tubes Using Artificial Neural Networks, Gregory J. Zdaniuk Dec 2006

Heat Transfer And Friction In Helically-Finned Tubes Using Artificial Neural Networks, Gregory J. Zdaniuk

Theses and Dissertations

The last few decades have seen a significant development of complex heat transfer enhancement geometries such as a helicallyinned tube. The arising problem is that as the fins become more complex, so does the prediction of their performance. In addition to discussing existing prediction tools, this dissertation demonstrates the successful use of artificial neural networks as a correlating method for experimentally- measured heat transfer and friction data of helicallyinned tubes.

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Hyperspectral Dimensionality Reduction Via Sequential Parametric Projection Pursuits For Automated Invasive Species Target Recognition, Terrance Roshad West Dec 2006

Hyperspectral Dimensionality Reduction Via Sequential Parametric Projection Pursuits For Automated Invasive Species Target Recognition, Terrance Roshad West

Theses and Dissertations

This thesis investigates the use of sequential parametric projection pursuits (SPPP) for hyperspectral dimensionality reduction and invasive species target recognition. The SPPP method is implemented in a top-down fashion, where hyperspectral bands are used to form an increasing number of smaller groups, with each group being projected onto a subspace of dimensionality one. Both supervised and unsupervised potential projections are investigated for their use in the SPPP method. Fisher?s linear discriminant analysis (LDA) is used as a potential supervised projection. Average, Gaussian-weighted average, and principal component analysis (PCA) are used as potential unsupervised projections. The Bhattacharyya distance is used as …

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Single-Step Treatment Of 2,4-Dinitrotoluene Via Zero-Valent Metal Reduction And Chemical Oxidation, J. Mathew Thomas Dec 2006

Single-Step Treatment Of 2,4-Dinitrotoluene Via Zero-Valent Metal Reduction And Chemical Oxidation, J. Mathew Thomas

Theses and Dissertations

Many nitroaromatic compounds (NACs) are considered toxic and potential carcinogens. The purpose of this study was to develop an integrated reductive/oxidative process for treating NAC contaminated waters. The process consists of the combination of zero-valent manganese or iron and a hydroxyl radical based treatment technique. Corrosion promoters were added to the contaminated water to minimize passivation of the metallic species. Water contaminated with 2,4-dinitrotoluen (DNT) was treated with the integrated process using a recirculating batch reactor. It was demonstrated that addition of corrosion promoters to the contaminated water enhanced the rate of reaction of 2,4-DNT with zero-valent iron or manganese. …

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Study Of Spin-Lattice Relaxation Rates In Solids:Lattice-Frame Method Compared With Quantum Density-Matrix Method, And Glauber Dynamic, Lazarus Solomon Dec 2006

Study Of Spin-Lattice Relaxation Rates In Solids:Lattice-Frame Method Compared With Quantum Density-Matrix Method, And Glauber Dynamic, Lazarus Solomon

Theses and Dissertations

The spin-lattice relaxation rates are calculated for a rigid magnetic spin cluster in an elastic medium in the presence of a magnetic eld using the latticerame method. This rate is then compared with both the rate calculated using the quantum mechanical densitymatrix method and with the Glauber dynamics. These calculation results are used in the contribution of various heat baths, such as a phonon bath in various dimensions or a fermionic bath, to transition rates that enter into dynamic Monte Carlo simulations of molecular magnets and nanomagnets.

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T-6a Texan Ii In-Flight Simulation And Variable Stability System Design, Kenneth Paul Germann Dec 2006

T-6a Texan Ii In-Flight Simulation And Variable Stability System Design, Kenneth Paul Germann

Theses and Dissertations

Inlight variable stability aircraft and inlight simulation are described. The uses of these vehicles and the associated requirements are described. Several forms of control architecture are identified for use in a T-6A inlight simulator. A non-linear model of the T-6A Texan II is developed for use in MATLAB/SIMULINK®. This model is used to design a feedforward responseeedback controller, based on simplified dynamic inversion. This controller is shown to exercise precise control over the T-6A host aircraft dynamics. This architecture is then used to demonstrate simulation of the A-4 and the F-15 by the T-6A. In addition to proving simplified dynamic …

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Installation And Instrumentation Of A Micro-Chp Demonstration Facility, Nicholas Alexander Stone Dec 2006

Installation And Instrumentation Of A Micro-Chp Demonstration Facility, Nicholas Alexander Stone

Theses and Dissertations

Micro-Cooling, Heating and Power (CHP) is the decentralized generation of electricity in which normally wasted heat is recovered for use in heating and cooling of the space. A micro-CHP demonstration facility is needed to showcase the system and allow for experiments to be performed. This thesis illustrates the steps taken for the installation and instrumentation of a Micro-CHP (Cooling, Heating, and Power) demonstration facility. Equipment sizing was performed by creating an accurate building model and performing a transient building analysis. Temperature, pressure, flow rate, and relative humidity are measured in order to determine accurate energy balances through each piece of …

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Measures Of Oxidation Of Soybean And Catfish Oils, John Michael Mcgillivray Dec 2006

Measures Of Oxidation Of Soybean And Catfish Oils, John Michael Mcgillivray

Theses and Dissertations

Oils from soybeans and catfish by-products were extracted using hexane, propane, and supercritical carbon dioxide (SCCO2). Free fatty acids (FFA), peroxide values (PV), anisidine values (AnV), total oxidation (TOTOX), induction point (IP), iodine values (IV), and 2-thiobarbituric acid reactive substance (TBARS) were all measured to analyze oxidation of these oils. The extraction yield of propane, hexane, and SCCO2 oils was 80.4, 94.5, and 90%, in respect to total lipid content. Oils extracted with SCCO2 were more oxidized than those extracted with propane and hexane; probably due to the higher temperature and longer extraction time. The IP correlated with AnV, IV, …

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The Chemical And Mechanical Effects Of Binding Chitosan To Implant Quality Titanium, Holly Joy Martin Dec 2006

The Chemical And Mechanical Effects Of Binding Chitosan To Implant Quality Titanium, Holly Joy Martin

Theses and Dissertations

Biomedical implants are commonly made from commercially pure titanium and other metal alloys, which are chosen for their strength and density. To improve the stability and promote bone cell growth into the implant, efforts to bond coatings to metal have been extensively studied. Many coatings used are considered bioactive, which promote the adhesion and growth of the bone cells surrounding the implant [A.1]. Of these, the most commonly investigated coating is a ceramic called hydroxyapatite, which is brittle, leading to flaking and inadequate bone cell growth [A.2]. Alternate bioactive coatings are being examined, including chitosan, the deacetylated form of chitin. …

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Rans And Hybrid Rans/Les Computations For Three-Dimensional Wings With Ice Accretion, Mithun Varma Mankada Covilakom Dec 2006

Rans And Hybrid Rans/Les Computations For Three-Dimensional Wings With Ice Accretion, Mithun Varma Mankada Covilakom

Theses and Dissertations

Computational investigations were carried out to evaluate the effectiveness and usability of hybrid RANS/LES techniques for predicting the unsteady separated flow over wings with ice accretion. RANS and hybrid RANS/LES computations were performed using the viscous flow solver CHEM with the SST turbulence model. Two configurations were considered during the study: an extruded wing with a glaze-ice shape and a swept wing with a simulated glaze-ice accretion. Hybrid RANS/LES results, in general, predict a less active shear layer ``roll up' than seen in the experimental data. Qualitative improvements are seen in the hybrid RANS/LES results over corresponding RANS results. The …

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Real-Time Vehicle Performance Monitoring With Data Integrity, William George Jenkins Dec 2006

Real-Time Vehicle Performance Monitoring With Data Integrity, William George Jenkins

Theses and Dissertations

A cornerstone of next generation intelligent transportation systems (ITS) is a seamless integration of in-vehicle networking with existing wireless telephony infrastructure. Remote access to on-board diagnostics and performance data is a crucial requirement for ITS. This thesis investigated the performance benefits of a data integrity buffering technique for an extensible vehicle position and performance tracking system (VPPTS). In support of this investigation, a VPPTS prototype was developed. The prototype used available technologies and interfaces to industry-standard communications channels and is a demonstration of a next-generation intelligent transportation system (ITS). The data integrity buffering technique under investigation was shown to provide …

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Recreational Incidents Liability Insurance And Judicial Interpretation For Fee Access Activities On Nonindustrial Private Forest Lands In Mississippi, Sangita Pokharel Dec 2006

Recreational Incidents Liability Insurance And Judicial Interpretation For Fee Access Activities On Nonindustrial Private Forest Lands In Mississippi, Sangita Pokharel

Theses and Dissertations

Private landowners refrain to open their land for recreational users in the fear of potential liability. This study covered the extent of liability, actual bodily injuries and property damages sustained by hunters and anglers in Mississippi. In order to aid for comparison, the study was divided in two sections. First it examined the risk and liability in fee access recreation through the review of court cases from 1904 to 2005. Second study explored the extent of actual bodily injuries and property damages sustained by hunters and anglers in Mississippi during 2002/03 to 2004/05 using telephone survey. It was found that …

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The Relationship Between School-Based Technology Facilitators, Technology Usage, And Teacher Technology Skill Levels In K-12 Schools In The Create For Mississippi Project, Sean Michael Owen Dec 2006

The Relationship Between School-Based Technology Facilitators, Technology Usage, And Teacher Technology Skill Levels In K-12 Schools In The Create For Mississippi Project, Sean Michael Owen

Theses and Dissertations

The purpose of this study was to explore the relationship between on-site Technology Facilitators, access to technology, technology usage, and technology skill levels of teachers at the eleven C?R?E?A?T?E for Mississippi Partner Schools in the 2003-2004 school year. Four hundred eighteen certified teachers, seven Technology Facilitators, and two Technology Aides participated in the C?R?E?A?T?E for Mississippi project in this time frame in the Partner Schools. Mean difference scores relative to teachers? beginner technology skills and advanced technology skills showed greater gains in Partner Schools that had some level of on-site support than Partner Schools that did not have on-site support. …

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The Use Of Dietary Fat Supplementation On Growth, Reproduction And Performance Characteristics Of Replacement Beef Heifers, Alecsandro Rufino Dos Santos Dec 2006

The Use Of Dietary Fat Supplementation On Growth, Reproduction And Performance Characteristics Of Replacement Beef Heifers, Alecsandro Rufino Dos Santos

Theses and Dissertations

The purpose of these studies was to evaluate the effects of a dietary fat supplementation on growth, reproduction and performance characteristics of replacement beef heifers reared in different management systems (pasture and dry lot conditions). The objectives were (1) to quantify changes in body composition traits and growth performance of replacement beef heifers fed different levels of fat in the supplemented diet,(2) to determine the reproductive performance of heifers supplemented with dietary fat in either a ryegrass pasture system or a dry lot system, and (3) to determine the value of real-time ultrasound technology (RTU) as an alternative technology to …

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When Brand Extensions Backfire: Exploring The Reciprocal Effect Of Negative Information Of Brand Extensions On Parent Brand, Lin Zhang Dec 2006

When Brand Extensions Backfire: Exploring The Reciprocal Effect Of Negative Information Of Brand Extensions On Parent Brand, Lin Zhang

Theses and Dissertations

Brand equity has been highlighted as one of the most valuable assets one company possesses. However, negative information related with brand extension, such as brand extension failures, can lead to negative perceptions, which may be difficult to reverse. Therefore, it is of critical interest to managers and academicians to have better understanding of the effect of brand extension on the parent brand, especially its negative effect. In this research, the focus is to investigate the feedback effect of negative information of brand extension on the parent brand. This dissertation focuses on how negative information of brand extension impacts the parent …

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The Influence Of Instructional Coaches On Improving Teaching And Student Performance, Mariella Hodges Simons Dec 2006

The Influence Of Instructional Coaches On Improving Teaching And Student Performance, Mariella Hodges Simons

Theses and Dissertations

Instructional coaching is emerging as a job-embedded professional development tool for schools to utilize in an effort to improve teaching practice and student achievement. Since there is a lack of understanding of the differing roles served by instructional coaches in schools and the functions they perform that influence teacher utilization of best practice procedures in teaching, this study concentrated on giving voice to teachers and administrators regarding their concerns and changes in teaching behavior. By listening to the assertions of educators employed within the schools housing an instructional coach, it is possible to gain an in-depth understanding of how the …

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The Osmotic Second Virial Coefficient As A Predictor Of Protein Stability, Kusum S. Verma Dec 2006

The Osmotic Second Virial Coefficient As A Predictor Of Protein Stability, Kusum S. Verma

Theses and Dissertations

The number of protein containing therapeutic drugs is growing day by day. Lack of proper storage conditions can cause protein degradation or aggregation. The osmotic second virial coefficient, B22, is a thermodynamic parameter, which can predict protein interaction with other proteins and solvent molecules. B22 has been successfully used as predictor of crystallization conditions for a protein in the solution, and in this study an attempt has been made to relate B22 as a predictor of stability of the protein. Static light scattering was used to measure B22 in our studies. B22 and the solubility of three proteins were measured …

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User Involvement And Perceived Usefulness Of Information Technology, Sanabel El-Hakeem El-Attar Dec 2006

User Involvement And Perceived Usefulness Of Information Technology, Sanabel El-Hakeem El-Attar

Theses and Dissertations

The present research investigated the extent to which users? perceived usefulness of IT was related to: (1) the user involvement in its design and implementation; (2) the user hierarchical position in the organization; (3) user years of service in the bank; and (4) user years of experience in banking business. In addition, the researcher examined the differences between males and females regarding the user involvement in design, involvement in implementation, and perception of usefulness of Information Technology (IT). The fifty-two bank users who participated in the study were volunteers from a major bank in the State of Mississippi. Seven research …

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Semantics-Enabled Framework For Knowledge Discovery From Earth Observation Data, Surya Srinivas Durbha Dec 2006

Semantics-Enabled Framework For Knowledge Discovery From Earth Observation Data, Surya Srinivas Durbha

Theses and Dissertations

Earth observation data has increased significantly over the last decades with satellites collecting and transmitting to Earth receiving stations in excess of three terabytes of data a day. This data acquisition rate is a major challenge to the existing data exploitation and dissemination approaches. The lack of content and semantics based interactive information searching and retrieval capabilities from the image archives is an impediment to the use of the data. The proposed framework (Intelligent Interactive Image Knowledge retrieval-I3KR) is built around a concept-based model using domain dependant ontologies. An unsupervised segmentation algorithm is employed to extract homogeneous regions and calculate …

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Molecular-Genetic And Structural Analyses Of The Nifhdkx Proteins Of The Nitrogenase System, Surobhi Lahiri Dec 2006

Molecular-Genetic And Structural Analyses Of The Nifhdkx Proteins Of The Nitrogenase System, Surobhi Lahiri

Theses and Dissertations

The nitrogenase enzyme is the biochemical machiner responsible for the conversion of the largely unavailable nitrogen to the easily assimilable ammonia for living organisms by the process termed as biological nitrogen fixation (BNF). This study was focused on understanding the various structural and functional aspects of the nitrogenase enzyme related to maturation and assembly of the FeMo-cofactor (FeMoco) metallocluster of the MoFe protein (the site for final substrate reduction), development of a dimeric MoFe protein and the structural homology of nitrogenase with other metalloenzymes. This research was specifically directed towards the NifHDKX proteins in which the nifHDK genes are the …

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Bacterial Source Tracking Of A Watershed Impacted By Cattle Pastures, Celina Phelps Dec 2006

Bacterial Source Tracking Of A Watershed Impacted By Cattle Pastures, Celina Phelps

Theses and Dissertations

Pathogenic microorganisms introduced by cattle may be transported to distant locations via watershed runoff. Escherichia coli, Enterococcus spp., and Streptococcus spp. are a few species present in runoff from land impacted by humans, cattle, and wildlife. Initial data reveals that E. coli concentrations in water are greater in areas impacted by cattle than by humans. And, wildlife contributes greater concentration fluctuations than either humans or cattle. When cattle are removed from a pasture, the bacterial concentrations rapidly decrease; however, slight variations in cattle herd size do not appear to significantly influence these counts. Amplified fragment length polymorphisms (AFLP) and repeated-sequence …

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Endohedral And Exohedral Complexes Of Polyhedral Oligomeric Silsesquioxanes (Poss): Endohedral Clusters Of Si12 : A Theoretical Study, Delwar Hossain Dec 2006

Endohedral And Exohedral Complexes Of Polyhedral Oligomeric Silsesquioxanes (Poss): Endohedral Clusters Of Si12 : A Theoretical Study, Delwar Hossain

Theses and Dissertations

Two distinct research projects were carried out in this dissertation. In the first project the results of first principle calculations on endo- and exohedral complexes of polyhedral oligomeric silsesqiuoxanes (POSS) with atomic and ionic species were carried out. Detailed studies were performed on structures, stabilities and electronic properties of these complexes. The stabilities of the endohedral Tn-POSS ( n = 8, 10 and 12) complexes depends on both the cage size and the nature of the endohedral species. Alkali metal ion encapsulation leads to cage contraction. Electron density was transferred from the cage to the alkali metal cations. Halide encapsulation …

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A Study Of The Perceptions Of Mississippi Legislators Regarding The Mission And Goals Of Mississippi Community And Junior Colleges, Samuel Lee Jones Dec 2006

A Study Of The Perceptions Of Mississippi Legislators Regarding The Mission And Goals Of Mississippi Community And Junior Colleges, Samuel Lee Jones

Theses and Dissertations

This study examined the perceptions of the Mississippi legislature that served in the 2006 government session concerning community/junior college mission and goals. There were six research questions in the study pertaining to current and future goal statements. A discrepancy-type survey instrument was developed based on the Community College Goals Inventory developed by the Educational Testing Service and the American Association of Community and Junior Colleges (AACJC). Respondents were asked to rate 40 goal statements in terms of how important the goal statement ?is,? which was current, and how important it ?should be,? which was future. The following goal areas were …

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A Social Exchange Perspective Of Intention To Quit, Shawn Michael Keough Dec 2006

A Social Exchange Perspective Of Intention To Quit, Shawn Michael Keough

Theses and Dissertations

This dissertation introduces a social exchange perspective of intention to quit and examines the relationship of several work-related and non work-related variables with intention to quit. Specifically, the relationships between the following ? perceived organizational support (POS), perceived supervisor support (POS), family responsibility, kinship responsibility ? and intention to quit were examined. POS and PSS were examined to provide a better understanding of the role each plays in the development of intention to quit. Family responsibility and kinship responsibility were examined because prior research has generally ignored the role each may play in the development of intention to quit. A …

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Influence Of Food-Grade Ingredients On Offlavor Compounds In Catfish Fillets, Sovann Kin Dec 2006

Influence Of Food-Grade Ingredients On Offlavor Compounds In Catfish Fillets, Sovann Kin

Theses and Dissertations

The purpose of this study was to screen the effect of some food-grade ingredients on the off-odors caused by geosmin and 2-methylisoborneol (MIB) compounds in catfish fillets by sensory evaluation. The study revealed that geosmin and MIB odor intensity were reduced to different degrees when fillets were dipped in lime flavor (94% and 67%, respectively), 0.5% acetic acid (AA) (70% and 16%, respectively), hardwood liquid smoke (98% and 86%, respectively), or hickory liquid smoke (98% and 100% respectively) in cooked products. A 0.5% AA proved to be effective in decreasing odor intensity of geosmin (70%) in cooked products, whereas lime …

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