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Effects Of Corrosion Prevention Compounds And Overload Induced Residual Stress Field On Fatigue Life In Aluminum Alloy, Jin Hee Park Jan 2004

Effects Of Corrosion Prevention Compounds And Overload Induced Residual Stress Field On Fatigue Life In Aluminum Alloy, Jin Hee Park

LSU Master's Theses

Corrosion-Prevention Compounds (CPC) are commonly used to prevent corrosion in the aircraft industry. The presence of corrosive environment (salt-fog, water-fog, even dry air) on aircraft structures has detrimental effects on the integrity of aircraft components which reduces the fatigue life and may accelerate the crack growth rate in the structures. This thesis work is aimed at identifying the effect of CPC and corrosion fatigue on the fatigue life of test specimen. This study describes the results of an experimental study on aluminum alloy 2024-T3 with center-crack specimen to investigate the effect of CPC on fatigue life. Generally, these compounds contain …


The Effects Of Internal And External Context Reinstatement On Source Memory, Jeffrey Joseph Starns Jan 2004

The Effects Of Internal And External Context Reinstatement On Source Memory, Jeffrey Joseph Starns

LSU Master's Theses

Memory for attended aspects of an encoded event (item memory) is facilitated when features of the encoding context are reinstated at test, indicating that item and context features are bound together in memory traces (Smith, 1979). The present study investigated whether reinstated contextual features similarly enhance memory for other contextual details of an event (source memory). Participants studied words that appeared on either the top or bottom of the computer screen in either a large or small font size. Following the study phase, participants completed a recognition/source test in which they had to indicate the location in which they studied …


Analytical Separations Using Packed And Open-Tubular Capillary Electrochromatography, Constantina P. Kapnissi Jan 2004

Analytical Separations Using Packed And Open-Tubular Capillary Electrochromatography, Constantina P. Kapnissi

LSU Doctoral Dissertations

The goal of the research reported in this dissertation is to develop packed and open-tubular capillary electrochromatographic methods for improved achiral and chiral separations of various classes of analytes. The first part of this research involves the separation of seven benzodiazepines by the use of the packed mode of capillary electrochromatography (CEC) and a 40 cm packed bed of Reliasil 3 μm C18 stationary phase. Optimal conditions were established by varying the mobile phase, the amount of organic modifier, the buffer concentration, the applied voltage, and the column temperature. The second part of this research focuses on the open-tubular …


Identifying Students At Risk For Academic Failure: The Application Of A Prereferral Screening Model Including Responsiveness To Intervention, Susan Lockhart Gatti Jan 2004

Identifying Students At Risk For Academic Failure: The Application Of A Prereferral Screening Model Including Responsiveness To Intervention, Susan Lockhart Gatti

LSU Doctoral Dissertations

Increasing demands are continually placed on our education system to improve the educational outcomes of all children. To provide the best services to our children, appropriate screening, assessments, and intervention services need to be implemented within the school setting. The current study evaluated the relationship of a screening procedure (Screening to Enhance Educational Performance, STEEP; Witt, 1996) using curriculum-based measurement (CBM) and compared the results of the screening procedure to other commonly used problem nomination procedures for second, third, and fourth graders. The data were obtained from archival sources that resulted from a service and training project conducted jointly by …


Bakso (Traditional Indonesian Meatball) Properties With Postmortem Condition And Frozen Storage, Dino Rahardiyan Jan 2004

Bakso (Traditional Indonesian Meatball) Properties With Postmortem Condition And Frozen Storage, Dino Rahardiyan

LSU Master's Theses

Bakso is a finely comminuted boiled Indonesian meat product that is traditionally made of starch, salt and emulsified prerigor or early postmortem meat and often sold from street vendors. Recently processors have begun to commercially manufacture bakso. This research was conducted to investigate the substitution of early postmortem meat with postrigor meat to allow more efficient manufacturing and raw material procurement. The first experiment was to determine the properties of bakso with three tapioca starch concentrations added to early or late postmortem beef. No differences (p<0.05) were observed in bakso properties of composition and texture, though bakso made of post-rigor meat had slightly less elasticity, strength and shear. These disadvantages were compensated by incorporating 15% starch concentration, indicating that the replacement of early postmortem meat with postrigor meat was applicable in industrial mass production of bakso. The second phase of experiments was to investigate the properties of bakso with different frozen storage times of raw postrigor meat and after different times of frozen storage for bakso made from postrigor and early postmortem meat. Postrigor meat substitution for early postmortem meat in bakso with 15% tapioca starch resulted in minimum composition and textural differences (p>0.05). Meat stored frozen for 2 and 4 months was still suitable as raw …


Bees Associated With Louisiana Longleaf Pine Savannas, Chanda Sara Bartholomew Jan 2004

Bees Associated With Louisiana Longleaf Pine Savannas, Chanda Sara Bartholomew

LSU Master's Theses

Longleaf pine savannas are perhaps the most threatened ecosystems in North America. Despite a well documented and highly diverse flora, little has been published on insects in general and, in particular, on bees that provide the valuable service of plant pollination. Thus, the aims of this study were to: 1) survey bees found in two savanna types in southeastern Louisiana; and 2) contrast the diversity and species composition of these two savanna types. An ancillary goal was to contrast two collecting protocols for bees in the savanna habitat. Overall, a total of 3,407 bees were collected representing 125 species. Of …


Isolation Of Aflatoxin-Free Lutein From Aflatoxin-Contaminated Corn, Evdokia Menelaou Jan 2004

Isolation Of Aflatoxin-Free Lutein From Aflatoxin-Contaminated Corn, Evdokia Menelaou

LSU Master's Theses

Lutein (3,3’-dihydroxy-alpha-carotene) has been identified by the Age-Related Eye Disease Study (AREDS) of the National Institute of Health (NIH) as a dietary compound with the ability to delay the onset and/or progression of age-related and/or diabetes-related vision loss. Lutein can also be useful in the prevention of other angiogenic diseases such as breast and colon cancer. Although marigold (Tagetes erecta) flowers are an excellent source of lutein, corn (Zea mays) has been identified as a very economical source of lutein because more value-added products, such as lutein, oil, and zein (known for its anti-microbial and anti-hypertensive activities) can be isolated …


The Control, Survival, And Growth Of Listeria Monocytogenes On Food Products, Richelle Lynn Beverly Jan 2004

The Control, Survival, And Growth Of Listeria Monocytogenes On Food Products, Richelle Lynn Beverly

LSU Doctoral Dissertations

Listeria monocytogenes, a ubiquitous foodborne pathogen, was recognized over 70 years ago. It is the source of the human disease listeriosis. The majority of Listeria monocytogenes that have been isolated from food product or human cases are of the serotypes ½ a, ½ b and 4b. Due to the recent outbreaks, recalls and deaths associated with Listeria monocytogenes in ready-to-eat meat products, the United States Department of Agriculture (USDA), Food Safety and Inspection Service (FSIS) on October 2, 2003 issued a directive for the control of Listeria monocytogenes on ready-to-eat products. The ready-to-eat food industry must impose a post-lethality treatment …


Chromosomal Localization Of A Proinsulin Transgene Inserted With A Transposon-Based Vector Into Japanese Quail, Coturnix Coturnix, Lacey R. Mcnally Jan 2004

Chromosomal Localization Of A Proinsulin Transgene Inserted With A Transposon-Based Vector Into Japanese Quail, Coturnix Coturnix, Lacey R. Mcnally

LSU Doctoral Dissertations

The overall goals of this research were to develop a reproducible method of detecting stable DNA insertion into Japanese quail and provide a method for gene location on avian chromosomes. This research resulted in the development of a different method of obtaining chromosome spreads in Japanese quail, the establishment of primed in situ hybridization as a method for the chromosomal gene detection in birds, development of Teflon-coated coverslip slides to facilitate laser microdissection of 0.5 ƒÝm samples, and chromosomal identification of proinsulin transgene insertions by laser microdissection and nucleotide sequence from G2 Japanese quail. The 28S rDNA was found on …


Route Planning Of Automated Guided Vehicles For Container Logistics, Sanjay Shankarrao Gurav Jan 2004

Route Planning Of Automated Guided Vehicles For Container Logistics, Sanjay Shankarrao Gurav

LSU Master's Theses

Automated guided vehicles (AGVs) are widely used in container terminals for the movement of material from shipping to the yard area and vice versa. Research in this area is directed toward the development of a path layout design and routing algorithms for container movement. The problem is to design a path layout and a routing algorithm that will route the AGVs along the bi-directional path so that the distance traveled will be minimized. This thesis presents a bi-directional path flow layout and a routing algorithm that guarantee conflict-free, shortest time routes for AGVs. Based on the path layout, a routing …


Activity-Based Anorexia: The Effects Of Resistant Starch, Holly M. Nguyen Jan 2004

Activity-Based Anorexia: The Effects Of Resistant Starch, Holly M. Nguyen

LSU Master's Theses

Anorexia nervosa is the third most common illness among adolescent females. Approximately one half the cases of anorexia nervosa have been suggested to be activity-induced. Various animal studies have been used to study human anorexia, particularly the activity-based anorexia model (ABA). The ABA paradigm consists of diet restriction and liberal access to activity, which ultimately results in a rapid decrease in both body weight and food intake paradoxical to the significant increase in activity. Because resistant starch (RS) has been shown to initiate a lower rise and a steady level of post-prandial blood glucose, it was hypothesized that a diet …


The Effectiveness Of Language-Literacy Training For Child Care Workers, Katelyn Beth Venturella Jan 2004

The Effectiveness Of Language-Literacy Training For Child Care Workers, Katelyn Beth Venturella

LSU Master's Theses

The purpose of the current study was to examine the effectiveness of group-based language-literacy training for child care workers. The first phase of the study followed a pre-post single group comparison design and involved 23 child care providers. The independent variable was the teacher training and the dependant variable was scores from a questionnaire. The second phase of the study involved a sub-group of four child care workers who received one-on-one follow up training after the group sessions. The questionnaire was administered a third time to the follow-up group. An analysis of the questionnaire items at pretest indicated that the …


Synthesis And Antibacterial Assessment Of Water-Soluble Hydrophobic Chitosan Derivatives Bearing Quaternary Ammonium Functionality, Mrunal R. Thatte Jan 2004

Synthesis And Antibacterial Assessment Of Water-Soluble Hydrophobic Chitosan Derivatives Bearing Quaternary Ammonium Functionality, Mrunal R. Thatte

LSU Doctoral Dissertations

Chitosan is a naturally occurring, bio-degradable, non-toxic, non-allergenic bio-polysaccharide derived from chitin, found in abundance in nature. Studies aimed at deriving newer applications of chitosan are hence of interest. Among these, one of the focuses of investigations is aimed at excellent antimicrobial activity demonstrated by chitosan. In this context, certain quaternary ammonium derivatives of chitosan have been shown in the past to be highly effective antibacterial materials. In the present study, substituted chitosan derivatives were synthesized and further quaternized using Quat-188 to produce water soluble derivatives at neutral pH. The antibacterial assessments of the quaternized derivatives of substituted chitosan were …


Effect Of Cotton Aphids, Aphis Gossypii (Glover), On Cotton Plant Development And Yield Components, Robert Hankins Jones Jan 2004

Effect Of Cotton Aphids, Aphis Gossypii (Glover), On Cotton Plant Development And Yield Components, Robert Hankins Jones

LSU Master's Theses

The effect of cotton aphids, Aphis gossypii (Glover), on cotton plant development and yield was studied during 2000 and 2001. Tests were conducted at the Macon Ridge Station (Winnsboro, Louisiana) in 2000 and 2001, and at the Northeast Research Station (St. Joseph, Louisiana) in 2001. Tests were performed in irrigated and non-irrigated regimes using individual plant comparisons, micro-plots, and whole plots. In both years and at both locations, cotton aphid densities induced chlorosis, and a downward cupping of leaves during the infestation period. The insecticides, pymetrozine and thiamethoxam, were applied to control natural infestations of cotton aphids. Although pymetrozine and …


Species Diversity And Biogeography Of Ants (Hymenoptera: Formicidae) In Louisiana With Notes On Their Ecology, Shawn T. Dash Jan 2004

Species Diversity And Biogeography Of Ants (Hymenoptera: Formicidae) In Louisiana With Notes On Their Ecology, Shawn T. Dash

LSU Master's Theses

Over three decades have passed since the completion of Moser and Blum's (1960) treatment of the ants of Louisiana. This research represents a significant contribution to and update of their work. I report the first-ever comprehensive assessment of the Louisiana Formicid fauna. More than 100 species from 38 genera and eight subfamilies are covered. This faunistic survey gives valuable data of biodiversity and macro/microhabitat selection of ant species. Included are keys to all subfamilies, genera, and species with illustrations photographs, and a regional map for each species.