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1999

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Characterization Of Solidification/Stabilization Of Chromium Wastes In Cement Matrix., Aijun Zhang Jan 1999

Characterization Of Solidification/Stabilization Of Chromium Wastes In Cement Matrix., Aijun Zhang

LSU Historical Dissertations and Theses

A cement-based solidification/stabilization (S/S) system of Cr wastes treatment has been studied in this program. A combination of the two techniques; namely reduction of Cr(VI) to Cr(III) and simultaneous immobilization within a cement matrix, has been found to be effective and practical to treat Cr wastes. Cr(VI) can not be easily and effectively-immobilized in the S/S system unless being reduced to Cr(III). Ferrous compounds are used as reducing reagents. The reduction not only removes the toxic Cr(VI) species but also results in the low-solubility precipitation of (CrxFe 1-x) (OH)3(s) in the S/S system. Long-term and short-term samples were tested through …


Sire Differences For Growth And Carcass Traits Of Purebred Brahman Steers., Trent Smith Jan 1999

Sire Differences For Growth And Carcass Traits Of Purebred Brahman Steers., Trent Smith

LSU Historical Dissertations and Theses

Purebred Brahman steers (n = 169) sired by 23 Gray and 8 Red Brahman bulls were evaluated for postweaning growth and carcass traits. Spring-born paternal half-sib male calves were purchased from private producers at weaning, backgrounded, and grazed on ryegrass for an average of 161 d. Following grazing, the steers were shipped to a commercial feedlot in south Texas for feeding. Steers were slaughtered in groups of about 45 head when they reached an approximate average endpoint weight of 530 kg and 1 cm backfat. All carcasses were subjected to high voltage electrical stimulation during slaughter. After a 24 hr …


Production Of Transgenic Eastern Oysters., John Terrell Buchanan Jan 1999

Production Of Transgenic Eastern Oysters., John Terrell Buchanan

LSU Historical Dissertations and Theses

The eastern oyster, Crassostrea virginica, supports a valuable industry in the United States and Louisiana. In recent years this industry has been plagued by diseases, creating interest in the use of gene transfer to produce oysters capable of eliminating pathogens. The goal of this work was to develop techniques for laboratory research of eastern oysters, and for transfer of genes to oyster gametes, larvae, and adults. Cell culture provides an effective alternative to work in whole animals. Cell attachment and spreading on various culture substrates was improved, and poly-D-lysine was identified as a superior substrate. Toxicity of the antibiotic G418 …


Molecular Genetics And Functions Of Herpes Simplex Virus Type 1 (Hsv-1) Glycoprotein K (Gk) In The Morphogenesis Of Infectious Virion Particles., Timothy Paul Foster Jan 1999

Molecular Genetics And Functions Of Herpes Simplex Virus Type 1 (Hsv-1) Glycoprotein K (Gk) In The Morphogenesis Of Infectious Virion Particles., Timothy Paul Foster

LSU Historical Dissertations and Theses

Herpes simplex virus type 1 (HSV-1) specifies at least 11 glycoproteins that are expressed in infected cells and in virions. HSV-1 enters into cells via fusion of the viral envelope with cellular membranes and can spread to adjacent cells via fusion of cellular membranes. Glycoproteins gB, gD, gH, and gL are known to be essential for virus entry, virus spread, and virus induced cell-to-cell fusion. The majority of spontaneous single amino acid changes that cause extensive cell fusion map within the UL53 gene encoding glycoprotein K (gK); however, the role of gK in virus entry and virus egress had not …


Experimental Mammalian Predator Removal And Other Factors Affecting Dabbling Duck Reproduction In North Dakota., Pamela Renee Garrettson Jan 1999

Experimental Mammalian Predator Removal And Other Factors Affecting Dabbling Duck Reproduction In North Dakota., Pamela Renee Garrettson

LSU Historical Dissertations and Theses

In the prairie pothole region, high predation rates often reduce duck nest success below the 15--20% thought necessary for population stability. Lethal removal of mammalian predators of duck nests is one potential management option, but there is little reliable information about the effects on nest success of removing mammalian predators without using poisons. On 16 4,150-ha blocks, half of them trapped during spring and summer, I found higher ( P < 0.001) nest success on trapped sites (45%) than on untrapped sites (17%). There were no year (P = 0.296), year-treatment (P = 0.423), or species-treatment (P > 0.895) effects. Nest success of blue-winged teal (Anas discors) and gadwalls (A. strepera) was higher than that of mallards ( A. platyrhynchos) and pintails (A. acuta, P = 0.028) on …


Toxicity Of Neem-Based Insecticides On Aquatic Animals And Cell Lines., Ipek Goktepe Jan 1999

Toxicity Of Neem-Based Insecticides On Aquatic Animals And Cell Lines., Ipek Goktepe

LSU Historical Dissertations and Theses

The impact of pure azadirachtin (AZA) and neem-based insecticides (Neemix(TM) and Bioneem(TM)) on eight aquatic animals (crayfish, white shrimp, grass shrimp, blue crab, water fleas, oyster, freshwater snails, and mosquito) and two cells (hybridoma and oyster) were assessed by short term acute toxicity tests of 48 and 96 h. The LC50 (in vivo bioassays) and IC50 (in vitro bioassays) were determined for each species. Stability of (Neemix(TM) and Bioneem(TM)) was tested under light, air, and heat (24 and 37°C) for 1, 3, 6, and 9 days. Neemix(TM) and Bioneem(TM)) were fractionated into two fractions (volatiles and nonvolatiles) and toxicities of …


Gaps In College Biology Students' Understanding Of Photosynthesis: Implications For Human Constructivist Learning Theory And College Classroom Practice., Phyllis Baudoin Griffard Jan 1999

Gaps In College Biology Students' Understanding Of Photosynthesis: Implications For Human Constructivist Learning Theory And College Classroom Practice., Phyllis Baudoin Griffard

LSU Historical Dissertations and Theses

The main research question of this study was: What gaps in biochemical understanding are revealed by a range of university introductory biology students as they work through a critically acclaimed multimedia program on photosynthesis, and what are the corresponding implications for elaboration of the Ausubel-Novak-Gowin Learning Theory (ANG, now Human Constructivism)? Twelve students, mixed for ability, gender and ethnicity, were recruited from two sections of "Bio 101." Before and after instruction in photosynthesis, in-depth clinical interviews were conducted during which participants completed a range of cognitive tasks such as sorting, concept mapping, explaining and predicting. Some tasks involved interacting with …


Development Of Pseudostationary Phases For Separations In Electrokinetic Chromatography., Judson Leroy Haynes Iii Jan 1999

Development Of Pseudostationary Phases For Separations In Electrokinetic Chromatography., Judson Leroy Haynes Iii

LSU Historical Dissertations and Theses

The research presented in this dissertation covers pseudo-stationary phase development for separations in electrokinetic chromatography (EKC). Micelles and cyclodextrins have traditionally served as the most popular pseudo-stationary phases (PSPs) used in EKC. However, the development and implementation of PSPs, which have improved properties over traditional ones, are necessary to extend the utility of electrokinetic chromatography. This dissertation covers research contributions, chapter by chapter, to the area of PSP development made by the author. In addition to this, Chapter 1 covers a brief history of chromatography and the fundamentals of capillary electrophoresis and EKC. The first pseudo-stationary phase developed was a …


The Evolution Of The Red River Valley Settlement System, 1714--1860., Keumsoo Hong Jan 1999

The Evolution Of The Red River Valley Settlement System, 1714--1860., Keumsoo Hong

LSU Historical Dissertations and Theses

Since the first European settlement was established in the middle of Indian territory in 1714, the Red River Valley had experienced a dramatic transformation until the end of the antebellum period. The trajectory of the evolution can be divided into five vertical cross sections. The formative phase (1714--1803) features the colonial regimes in political arena, less-specialized regional economies, nascent urban units laden heavily with defensive functions, and coerced labor system. The settlement system resembled a semi-primate pattern with Natchitoches on the summit. The period of the Territory of Orleans (1804--1812) corresponded to the transition phase. During this interim, traditional staples …


Family Portraits: Contemporary Women Novelists And The Nuclear Family., Tamra Lynn Horton Jan 1999

Family Portraits: Contemporary Women Novelists And The Nuclear Family., Tamra Lynn Horton

LSU Historical Dissertations and Theses

A society whose economy becomes increasingly dependent on commodity fetishism cultivates obsessive materialistic desire in its subjects. The demand for mass consumerism buoys reification, a mania wherein human beings are analogous to goods and vice versa. Successful reification depends upon hegemonic apparatuses: social, legal, and political agencies of dominant ideology. Reification is perhaps most fully realized in the form of fetishized human relationships. In the United States today, the most coercive and unassailable hegemonic apparatus is the institutionalized nuclear family, a social and legal affiliation between individuals so dogmatically fetishized as to have become compulsory. Contemporary American women writers are …


Factors Influencing Effectiveness Of Exhibit Displays On Family Learning In A Public Aquarium., Kodi Rae Jeffery Jan 1999

Factors Influencing Effectiveness Of Exhibit Displays On Family Learning In A Public Aquarium., Kodi Rae Jeffery

LSU Historical Dissertations and Theses

An important goal in science education reform is to create a scientifically literate society. The American Association for the Advancement of Science (1989b) has stated that for people to understand biology, they must first have personal experiences with it. There are severe limitations on the types of firsthand biology experiences available in the classroom. Informal learning institutions, however, are not limited by these constraints. Visitors enjoy a free-choice environment, where they can thoroughly explore things unavailable in most classrooms. Thus, museums are key resources that may help society achieve scientific literacy. This study asked what aspects of the Aquarium of …


Development Of Efficient Rice Dna Transformation Methods And Rapid Evaluation Of Transgenic Lines., Junda Jiang Jan 1999

Development Of Efficient Rice Dna Transformation Methods And Rapid Evaluation Of Transgenic Lines., Junda Jiang

LSU Historical Dissertations and Theses

A rapid and efficient method was developed for production and field evaluation of transgenic herbicide resistant elite U.S. rice (Oryza sativa L.) lines and cultivars. Six elite U.S. rice lines, including the cultivar Cocodrie, were transformed for glufosinate (phosphinothricin) herbicide resistance by particle bombardment of mature seed-derived embryogenic calli with a synthetic pat gene or the bar gene from Streptomyces hygroscopicus. By utilizing optimized media for embryogenic callus induction and bialaphos or hygromycin B as a selection agent, 258 independent transformed calli, producing 1268 transgenic plants, were recovered from 5201 bombarded calli. Transformation efficiency ranged from 5% for breeding line …


Capability Of Recombinant Insect Viruses For Environmental Persistence And Transport., Yihua Lee Jan 1999

Capability Of Recombinant Insect Viruses For Environmental Persistence And Transport., Yihua Lee

LSU Historical Dissertations and Theses

Wild-type and recombinant nucleopolyhedroviruses (NPVs) were compared with respect to their capability to produce epizootics in Trichoplusis ni (Hubner) larvae infesting collards in a greenhouse microcosm. Viruses tested were variants of Autographa californica (Speyer) NPV (AcNPV): wild-type virus (AcNPV.WT), AcNPV expressing a scorpion toxin (AcNPV.AaIT), and AcNPV expressing juvenile hormone esterase (AcJHE.SG). Epizootics of AcNPV.WT lasted 8 weeks after a single viral release in the replicated, greenhouse micro-plots. AcJHE.SG epizootics also lasted 8 weeks after viral release, but this virus and AcNPV.AaIT were both out-competed by AcNPV.WT. AcNPV.AaIT was no longer detected in the T. ni population by the fourth …


Cryopreservation Of Gametes And Larvae Of The Eastern Oyster Crassostrea Virginica., Carmen G. Paniagua-Chavez Jan 1999

Cryopreservation Of Gametes And Larvae Of The Eastern Oyster Crassostrea Virginica., Carmen G. Paniagua-Chavez

LSU Historical Dissertations and Theses

Storage of gametes and larvae offers benefits for research and commercial oyster production and should be applicable in the hatchery at a commercial scale. We optimized refrigerated storage of eastern oyster sperm. Significant differences were found in the motility of sperm suspended in artificial sea water (ASW) of different osmotic pressures (P < 0.001). The highest motility was found in undiluted sperm and the lowest in 1:31 dilution. The greatest larval survival at 12 h (48%) was obtained with sperm diluted in calcium-free Hanks' balanced salt solution (C-F HBSS). Thus, for storage of longer than 1 d, it is best to leave samples undiluted. However, when sperm samples are diluted, it is best to maintain high sperm concentrations and to use C-F HBSS as an extender. Samples were frozen at -2.5°C/min, held for 5 min at -30°C, and plunged in liquid nitrogen using 10% propylene glycol (PG) as the cryoprotectant for sperm and 10% or 15% PG for trochophore larvae. Motility and fertilizing ability of thawed sperm were affected by cryoprotectant concentration and thawing temperature (P = 0.0001). Larval survival was affected by the concentration of larvae per straw (P = 0.0011). Frozen samples were transported to an oyster hatchery at Grand Isle, Louisiana. After 4 months, 1,000 oysters from the control group, 230 oysters produced from thawed sperm, and 850 oysters from thawed larvae were found. Oysters produced from thawed larvae developed normally in the hatchery, demonstrating opportunities for use of cryopreservation in research and aquaculture. Flow cytometry with the fluorescent dyes Sybr-14 and propidium iodide (PI) was used to assess membrane damage of thawed sperm, and rhodamine 123 and PI were used to assess mitochondrial function. Preliminary studies of cryopreservation of oyster eggs were performed. Fluorescein diacetate (FDA) was used to identify viable eggs. Dimethyl sulfoxide (0.88 M and 1.75 M) and sucrose (0.12 M and 0.25 M) were the least toxic cryoprotectants evaluated. The cooling rate yielding least damage to eggs was -1.5°C per min. However, only an average of 14 eggs (out of 200) were stained with FDA in thawed samples and none were fertilizable.


The Performance Of Prekindergarten Children On Representational Tasks Across Levels Of Displacement., Emily Flake Smith Jan 1999

The Performance Of Prekindergarten Children On Representational Tasks Across Levels Of Displacement., Emily Flake Smith

LSU Historical Dissertations and Theses

This investigation was guided by Nelson's (1996) experiential theory and the Situational-Discourse-Semantic (SDS) model of Norris and Hoffman (1993, 1997, in press) which was used to establish predictions regarding the representational difficulty of each of the task conditions. Subjects were 32 four-year-old children enrolled in four prekindergarten programs located within a small city in southern Louisiana and represented both lower and middle SES populations. The tasks required subjects to represent knowledge of the bedtime routine, ranging from personal enactments with props through generation of stories and event scripts for hypothetical situations. Performances were analyzed for content in terms of event …


Instantaneous Learning Neural Networks., Kun Won Tang Jan 1999

Instantaneous Learning Neural Networks., Kun Won Tang

LSU Historical Dissertations and Theses

Instantaneous learning is a desirable feature in neural networks. This type of learning enables the network to be trained very quickly, typically in just one or two passes of the training set as opposed to hundreds or even thousands of passes for networks trained by an iterative process, such as the error backpropagation (BP) algorithm. This dissertation first reviews several existing types of neural networks with instantaneous learning capability. It then proposes a new network called the Fuzzy Classification (FC) Neural Network that can be trained with two passes of the training samples. The first pass assigns the synaptic weights …


The Effects Of Rumen Undegradable Choline In The Nutrition And Metabolism Of Dairy Cows., Fernando Vazquez Jan 1999

The Effects Of Rumen Undegradable Choline In The Nutrition And Metabolism Of Dairy Cows., Fernando Vazquez

LSU Historical Dissertations and Theses

This study was conducted to determine whether supplemental rumen protected choline could improve lactation performance and lipid metabolism in cows in negative energy balance. In experiment 1, 19 primiparous Holstein cows were randomly assigned to dietary treatments consisting of either a control ration or control plus 15 g/d of supplemental rumen-protected choline (60 g/d of Cap-Shure, Balchem Corp., Slate Hill, NY). Close-up and early lactation rations were formulated from a grass hay and corn silage forage base, respectively, with a corn-soy concentrate, whole cottonseed. and alfalfa hay included as appropriate to meet nutrient requirements. Cows were milked twice daily. Cows …


Effect Of Rice Cultural Practices On Rotational Crop Herbicide Carryover And Imazethapyr Efficacy., Wei Zhang Jan 1999

Effect Of Rice Cultural Practices On Rotational Crop Herbicide Carryover And Imazethapyr Efficacy., Wei Zhang

LSU Historical Dissertations and Theses

A two-year study was conducted to evaluate the possible interaction between rotational crop herbicides and herbicides used in water-seeded rice culture. Rice growth and yield reduction with rotational crop herbicides were not affected by the rice herbicides. However, the combination of molinate or thiobencarb with fluometuron, imazethapyr, metolachlor, or norflurazon at low residue levels further reduced rice heading compared with the corresponding rotational crop herbicide alone. Fluometuron and metolachlor residues at 1 to 2 half-lives have potential to injure rice and reduce rice yield in a water-seeded culture. Norflurazon injured rice and reduced rice yield at a residue level as …


The Effects Of Urbanization And Human Disturbance Upon Plant Community Structure And Bird Species Richness, Diversity, And Abundance In A Natural Forested Area (Forest Park) In Portland, Oregon, Nancy Ellen Broshot Jan 1999

The Effects Of Urbanization And Human Disturbance Upon Plant Community Structure And Bird Species Richness, Diversity, And Abundance In A Natural Forested Area (Forest Park) In Portland, Oregon, Nancy Ellen Broshot

Dissertations and Theses

The effects of urbanization and continual human disturbance on the plant and avian communities of Forest Park and forested lands surrounding Portland, Oregon, were studied. I examined characteristics of plant and avian communities at 25 sites, 24 which were in Forest Park and surrounding areas and one which was in the Ancient Forest Preserve (old-growth stand) northwest of Forest Park. Data were analyzed using multiple regression, ANOV A, and Bonferonni/Dunn. Seven variables were selected representing different urbanization gradients. An additional covariable coded for the old-growth stand, allowing it to be used as a control.

Many tree variables, especially those related …


A Submersible Battery-Powered Flow Injection (Fi) Sensor For The Determination Of Nitrate In Estuarine And Coastal Waters, Arj David, T Mccormack, Pj Worsfold Jan 1999

A Submersible Battery-Powered Flow Injection (Fi) Sensor For The Determination Of Nitrate In Estuarine And Coastal Waters, Arj David, T Mccormack, Pj Worsfold

School of Geography, Earth and Environmental Sciences

The design, construction and performance of a remotely deployed submersible flow injection-based nutrient (total oxidized nitrogen) sensor are described. The sensor featured a custom-built microcomputer and a solid-state, flow-through spectrophotometric detector, and the derivatization chemistry was based on in-line coppercadmium reduction of nitrate to nitrite, and diazotization with N1NED and sulphanilamide. The limit of detection was 0.0014 mg l-1 NO3-N and the linear range was 0.0014- 0.77 mg l-1 with a 260 μl sample volume and a 20 mm path length flow cell. Results from submersed deployments in the Tamar estuary and North Sea are also reported.


West Virginia's Adoption Statute: A History Of A Work In Progress, Lisa Kelly Jan 1999

West Virginia's Adoption Statute: A History Of A Work In Progress, Lisa Kelly

Articles

More than two years have passed since the Legislature reformed West Virginia's adoption statute. The goal of this article is to provide a kind of legislative history to deepen the reader's understanding of the current statute. This history will include an explanation of the West Virginia Law Institute's Proposal, as well as the Legislature's reaction to it. In Part II, I will detail this history. In Part III, I will explain the operation of the current statute, with mention of the few recent adoption decisions that have construed various provisions. In Part IV, I will look at some of the …


Policy And Science: A Review Essay Of Wilson's Consilience: The Unity Of Knowledge, Thomas Earl Geu Jan 1999

Policy And Science: A Review Essay Of Wilson's Consilience: The Unity Of Knowledge, Thomas Earl Geu

South Dakota Law Review

No abstract provided.


The Harm In The Application Of The Harmless Error Doctrine To The Constitutional Defect In In Re C.V., Denise M. Faehnrich Jan 1999

The Harm In The Application Of The Harmless Error Doctrine To The Constitutional Defect In In Re C.V., Denise M. Faehnrich

South Dakota Law Review

No abstract provided.


Morphology And Development Of Several External Myiasis Larvae Recorded In Elazığ, Cem Ecmel Şaki̇, Edi̇p Özer Jan 1999

Morphology And Development Of Several External Myiasis Larvae Recorded In Elazığ, Cem Ecmel Şaki̇, Edi̇p Özer

Turkish Journal of Veterinary & Animal Sciences

A study was conducted on external myiasis of livestock in Elazığ and its districts (Sivrice, Kovancılar, Baskil and Salkaya) in 1994-1995. Eight species of myiasis flies including Lucilia sericata, L. caesar, Calliphora vicina, C. vomitoria, Chrysomya albiceps, Wohlfahrtia magnifica, Sarcophaga haemorrhoidalis and S. carnaria were determined and published seperately. In addition, morphological and biological characteristics of larvae of Lucilia sericata, Calliphora vicina, Wohlfahrtia magnifica and Sarcophaga haemorrhoidalis were investigated under laboratory conditions as well. The studies showed that development from larvae to fly was recognized in 17-22 days for L. sericata, 10-16 days for S. haemorrhoidalis, 19-23 days for C. …


Cover And Contents Jan 1999

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


Conjunctive Use Of Surface Water And Groundwater For Sustainable Agricultural Production, Richard C. Peralta Jan 1999

Conjunctive Use Of Surface Water And Groundwater For Sustainable Agricultural Production, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

This report is a guide to aid conjunctive water use in stream-aquifer systems. Conjunctive use refers to coordinated use of groundwater and surface water resources. This document discusses principles useful for field engineers and agricultural experts. It presents hydrologic and hydraulic principles and quantitative and qualitative parameters relating to sustainable conjunctive use. It provides tools and software.


Cover And Contents Jan 1999

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


Cover And Contents Jan 1999

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


Cover And Contents Jan 1999

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


Cover And Contents Jan 1999

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.