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LSU Historical Dissertations and Theses

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Articles 1921 - 1950 of 7798

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Advanced Gravitational Radiation Transducers With Small Mass And Ultra-Low Temperature Squids., Ziniu Geng Jan 1994

Advanced Gravitational Radiation Transducers With Small Mass And Ultra-Low Temperature Squids., Ziniu Geng

LSU Historical Dissertations and Theses

The transducer and SQUID are two major components for a resonant-mass gravitational wave antenna. They must always have high sensitivity and low noise. In this work, a two-mode superconducting inductive transducer for a three-mode gravitational wave bar antenna is designed. The construction and tests of small mass resonators that form the transducer are described. The experiments and test results of commercial dc SQUIDs at ultra-low temperature are discussed in detail. Special problems arise when SQUIDs are tested at ultra-low temperature in vacuum. We address the problems and provide proper solutions. Our experiments show that the dc SQUID made by Quantum …

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Development Of Nuclear Quadrupole Resonance Spectroscopic And Imaging Methods., Youngil Lee Jan 1994

Development Of Nuclear Quadrupole Resonance Spectroscopic And Imaging Methods., Youngil Lee

LSU Historical Dissertations and Theses

Solution-state nuclear magnetic resonance (NMR) of $\sp1$H and $\sp{13}$C nuclei in molecular species is very common as is solid-state NMR of $\sp{13}$C in a wide variety of substances. Yet many nuclei remain little studied by conventional NMR techniques, for example $\sp2$H, $\sp{11}$B, $\sp{14}$N, $\sp{79}$Br, $\sp{81}$Br, and $\sp{93}$Nb. One method for their study is nuclear quadrupole resonance (NQR). Briefly, the reason that quadrupolar nuclei are difficult to study with conventional NMR techniques is the exceedingly large line widths these nuclei exhibit in high magnetic fields. The first part of my dissertation deals with NQR spectroscopic techniques developed to obtain structural information …

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Selective Information Processing Of Body Size And Food Related Stimuli In Women Who Are Preoccupied With Body Size., Richard Daniel Fuller Jan 1994

Selective Information Processing Of Body Size And Food Related Stimuli In Women Who Are Preoccupied With Body Size., Richard Daniel Fuller

LSU Historical Dissertations and Theses

Overconcern or preoccupation with body size and weight is a central psychopathological feature of the eating disorders. The overconcern with body size is considered to be a function of fear of weight gain or "fear of fatness". Cognitive theories of psychopathology have hypothesized that fear results in an increased activation of cognitive structures associated with the feared object. This increased activation (priming) is hypothesized to enhance the processing of information related to the feared object. This study tested this hypothesis using a lexical decision task. Individuals with extreme body size preoccupation were evaluated for a selective information processing of body …

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Physiological Variation In Loblolly Pine (Pinus Taeda L.) As Related To Crown Position And Stand Density., Dennis Albert Gravatt Jan 1994

Physiological Variation In Loblolly Pine (Pinus Taeda L.) As Related To Crown Position And Stand Density., Dennis Albert Gravatt

LSU Historical Dissertations and Theses

Physiological parameters were measured under natural light conditions and needle orientation from towers and walkways erected in the crowns of loblolly pine (Pinus taeda L.) trees. Photosynthetic light response curves, chlorophyll content, nutrient content and specific leaf area were determined for current-year foliage on detached branches. Two silvicultural treatments were randomly assigned to the twelve plots in the fall of 1988. Plots were thinned to a density of 731 trees per hectare or left unthinned, at a density of 2990 trees per hectare. The plots were left unfertilized or fertilized with 744 kg per hectare of diammonium triple superphosphate was …

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Interactions Of Mouse And Bovine Preimplantation Embryos Prior To And After The In Vitro Developmental Block Stage., Leyi Li Jan 1994

Interactions Of Mouse And Bovine Preimplantation Embryos Prior To And After The In Vitro Developmental Block Stage., Leyi Li

LSU Historical Dissertations and Theses

The objective of the present study was to evaluate the effect of post-block mouse and bovine embryos on the development of pre-block embryos around the in vitro developmental block stage. The effect of the post-block embryos on the development of the pre-block embryos was evaluated in culture, in chimeras and in cytoplasmic hybrid embryos. The results indicate that post-block embryos were able to stimulate the development of the pre-block embryos in culture. The stimulatory effect of the post-block mouse and bovine embryos was found not to be species-specific and was synergistic with that of bovine granulosa cells. Chimeric parthenogenetic bovine …

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Crust Formation In Soils Of Mexico And Louisiana., Miguel Angel Martinez-Gamino Jan 1994

Crust Formation In Soils Of Mexico And Louisiana., Miguel Angel Martinez-Gamino

LSU Historical Dissertations and Theses

Crust formation in three soils from Mexico (Nadurargid, Durustoll and Calciorthid) and three soils from Louisiana (two Fragiudalfs, and a Hapludalf) was investigated. The objectives were: (1) to characterize crust morphology; (2) to quantify type, distribution, and geochemistry of cementing agents; and (3) to evaluate the effect of management practices on infiltration, erosion, crust strength, and corn and soybean emergence. Three management practices, bare, protected, and gypsum-amended were evaluated. Crust morphology in the soils of Louisiana indicated the development of a compacted layer in the upper 0.1 mm of the bare and gypsum-amended soils. Aggregation was improved with the gypsum …

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A Step In The "Wright" Direction: Mapping The Structural Locations Of The "New Class"., David Emile Maurer Jan 1994

A Step In The "Wright" Direction: Mapping The Structural Locations Of The "New Class"., David Emile Maurer

LSU Historical Dissertations and Theses

Stratification researchers have directed their efforts toward tracing the emergence of and speculating about the composition of a New Class which is forming as American capitalism expands. In their endeavors, three sets of theories occupy center stage: Expert New Class theory, Managerial New Class theory, and New Working Class theory. To empirically test each of these theories, the 1991-1992 Class and Class Consciousness data set were employed. Of the three sets of theories, Managerial New Class models offer the most promise for future research and explaining the changing nature of the American social structure. Moderate support is also provided for …

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Study Of Shape Coexistence In Even-Even Neutron Deficient Mercury Isotopes., Paresh K. Joshi Jan 1994

Study Of Shape Coexistence In Even-Even Neutron Deficient Mercury Isotopes., Paresh K. Joshi

LSU Historical Dissertations and Theses

Nuclei in the neutron deficient Z $\le$ 82 region have attracted considerable attention since research at UNISOR first observed the nearly degenerate nuclear shape coexistence in $\sp{184-188}$Hg. The deformed prolate shapes in this region are believed to result from a proton pair excitation into the $h\sb{9/2}$ shell model orbital which lies above the closed proton shell at Z = 82. In the region far from stability (where the neutron shell is half filled), the degeneracy of the shape coexistence is maximum. These prolate deformed intruder states in the Hg isotopes have been identified in radioactive decay studies for neutron numbers …

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An Evaluation Of Southern Region Sustainable Agriculture Research And Education (Sare) Program Proposals For The Period 1992-1994., Ellis Mbaka Njoka Jan 1994

An Evaluation Of Southern Region Sustainable Agriculture Research And Education (Sare) Program Proposals For The Period 1992-1994., Ellis Mbaka Njoka

LSU Historical Dissertations and Theses

The purpose of this study was to describe and compare funded and unfunded research proposals submitted to the Southern Region Sustainable Agriculture Research and Education Council between 1992 and 1994. Coding reliability and validity were assessed through a pilot study after which the actual coding was carried out. A census of 32 funded and a simple random sample of 54 unfunded proposals were used for this study. Descriptive statistics (frequencies) were used to describe research themes, sustainable agricultural practices, research categories, funds requested for research, origin of proposals, length of research period, research cooperators, and the occupation of principal investigators. …

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Error Correction In Second-Year Students' Compositions: A Comparative Study Of Native And Non-Native Speakers/Instructors Of French., Catherine Annie Jolivet Jan 1994

Error Correction In Second-Year Students' Compositions: A Comparative Study Of Native And Non-Native Speakers/Instructors Of French., Catherine Annie Jolivet

LSU Historical Dissertations and Theses

The purpose of this dissertation was to determine whether or not there are differences between native and non-native speakers/instructors of French when they correct second year students' compositions. The research questions this study set forth to answer are: (1) Are there any differences in the number of corrections performed by native and non-native speakers/instructors of university intermediate French classes when they evaluate compositions? (2) Are there any differences between native and non-native speakers/instructors in the categories (verb, noun, spelling, other) where error correction was performed? (3) Are there any differences between native and non-native speakers/instructors when and if they paid …

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Elevation Of The Hatching Envelope In Penaeidea Shrimp: Morphology And Assembly., Patricia Stoops Glas Jan 1994

Elevation Of The Hatching Envelope In Penaeidea Shrimp: Morphology And Assembly., Patricia Stoops Glas

LSU Historical Dissertations and Theses

The appearance of extracellular coats around "eggs" are associated with activation of the oocytes. This coat, termed fertilization envelope (sea urchins), chorion (fish), zona pellucida (mammals), capsule (crab) or hatching envelope (HE) (shrimp) serves as a polyspermy block (Wasserman, 1982) or microenvironment protecting the egg from bacteria or other hostile elements (Kudo and Inoue, 1989; Kudo and Teshima, 1991; Kudo, 1992; Epel, 1993). HE assembly is described for penaeoid shrimp (Lynn, et al., 1991) and is, in contrast to many systems, a fertilization independent event. However, the mechanisms of assembly appear similar to extracellular coat formation in other animal systems …

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The Role Of Infaunal And Epifaunal Suspension Feeding Macrofauna On Rates Of Benthic-Pelagic Coupling In A Southeastern Estuary., Christine Miller-Way Jan 1994

The Role Of Infaunal And Epifaunal Suspension Feeding Macrofauna On Rates Of Benthic-Pelagic Coupling In A Southeastern Estuary., Christine Miller-Way

LSU Historical Dissertations and Theses

This research investigated the effects of two suspension feeding bivalves, the infaunal Rangia cuneata, and the epifaunal Crassostrea virginica, on benthic-pelagic coupling in Fourleague Bay, LA, a river-dominated estuary. A continuous-flow microcosm system was developed to overcome recognized limitations of batch methodology and to facilitate manipulations designed to investigate the ecological role of benthic macrofauna. Experiments comparing traditional batch methodology to continuous-flow methodology indicated that rates of benthic processes were consistently greater when measured using continuous-flow methodology. Examinations of concentrations indicated that differences were due to concentration gradients which departed from ambient over time in the batch cores. Over an …

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A Water Balance Evaluation Of The Effects Of Climate Variability And Human Modification On The Flow Regime Of The Mississippi River, 1932-1988., Judy Lee Hoff Jan 1994

A Water Balance Evaluation Of The Effects Of Climate Variability And Human Modification On The Flow Regime Of The Mississippi River, 1932-1988., Judy Lee Hoff

LSU Historical Dissertations and Theses

Human activities affecting runoff and streamflow within the Mississippi River drainage basin have been and continue to be significant. Since the disastrous flood of 1927, the U.S. Army Corps of Engineers has established an extensive regulatory system for flood control purposes and navigational benefits. Along with these river system modifications, significant landscape alterations have occurred within the basin as a result of cultural and economical development. In light of the dramatic Midwest flood of 1993, it becomes increasingly necessary to understand the comprehensive relationship between streamflow, climatic variability, and human-induced change within the overall drainage basin. A water balance methodology …

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The Impact Of Contextual Variables On The Propensity Of Individual Employees To Withhold Effort: A Multi-Organization Analysis., Roland E. Kidwell Jr Jan 1994

The Impact Of Contextual Variables On The Propensity Of Individual Employees To Withhold Effort: A Multi-Organization Analysis., Roland E. Kidwell Jr

LSU Historical Dissertations and Theses

This dissertation synthesizes theory and research in economics, social psychology, sociology and management to present and test a model of employee propensity to withhold effort (PWE) in work groups in 10 organizations. The dissertation extends to work organizations Knoke's (1990) synthesized motivation model, which suggests that rational, normative conformity and affective bonding incentives act together to predict whether people will contribute to collective activities. A study of 570 private-sector employees found that when employees perceived high degrees of task visibility, group effort norms, equity and altruism, they would be less likely to withhold effort in job-related tasks. As predicted, payment …

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Role Of Curved Dna In Promoter Recognition With Bacillus Subtilis And Escherichia Coli Rna Polymerase., Cheryl Anne Nickerson Jan 1994

Role Of Curved Dna In Promoter Recognition With Bacillus Subtilis And Escherichia Coli Rna Polymerase., Cheryl Anne Nickerson

LSU Historical Dissertations and Theses

Intrinsically curved DNA upstream of the RNA polymerase binding site, the promoter, influences transcription in Bacillus subtilis. In this study, curved DNA upstream of the $-$35 region was examined for the ability to influence transcription in Escherichia coli and B. subtilis through the use of hybrid promoters. These promoters were constructed by substituting the curved DNA from two B. subtilis promoters, Bal129 and Alu156, for the DNA upstream of the $-$35 region in the lambda phage promoters $p\sb{\rm R}$ and $p\sb{\rm L}$. The hybrid promoters were designated Bal$p\sb{\rm R}$, Alu$p\sb{\rm R}$, Bal$p\sb{\rm L}$, and Alu$p\sb{\rm L}$. Using transcriptional fusions between …

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Epidemiology Of Strongylate Nematode And Coccidia (Eimeria) Infection In Sheep With Special Reference To Breed Resistance., Mahesan Bahirathan Jan 1994

Epidemiology Of Strongylate Nematode And Coccidia (Eimeria) Infection In Sheep With Special Reference To Breed Resistance., Mahesan Bahirathan

LSU Historical Dissertations and Theses

In the United States, the annual production losses in small ruminants due to internal parasites has been estimated at $45 million. In 1992, 1993 and 1994, breed specific responses to naturally acquired strongylate nematode and coccidia ({\it Eimeria\/}) infections were compared in three classes (suckling lambs, weaned lambs, and mature ewes) of pure-bred Suffolk and sheep native to Louisiana (Native) which were grazed together on infective pasture. Parasitological (fecal egg counts and nematode counts) and hematological (packed cell volumes, total immunoglobulin levels, total and class-specific anti-{\it Haemonchus contortus\/} antibody levels and eosinophil counts) data were collected. In suckling Native lambs, …

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Evolutionary Patterns In Proteaceae Based On Comparative Floral And Inflorescence Ontogenies., Andrew William Douglas Jan 1994

Evolutionary Patterns In Proteaceae Based On Comparative Floral And Inflorescence Ontogenies., Andrew William Douglas

LSU Historical Dissertations and Theses

Comparative floral and inflorescence ontogenies among Proteaceae are examined and a phylogenetic analysis based on principles of parsimony is presented. Comparative developmental and morphological investigations indicate that the fourmerous flowers are primitively simple. Each flower is composed of: a single series of four tepals that are initiated in two dimerous whorls (in most taxa); four stamens, each one initiated opposite a tepal and generally fused to the tepal at various heights due to zonal growth; and a single carpel. Ontogenetic studies reveal that the nectaries arise late in development and are not homologous to a reduced petal or stamen whorl. …

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The Effect Of Carbon Dioxide Concentration On Carbonic Anhydrase And Other Proteins In Chlamydomonas Reinhardtii., Mamta Rawat Jan 1994

The Effect Of Carbon Dioxide Concentration On Carbonic Anhydrase And Other Proteins In Chlamydomonas Reinhardtii., Mamta Rawat

LSU Historical Dissertations and Theses

Unicellular green algae, like Chlamydomonas reinhardtii, are able to grow photoautotrophically at low levels of CO$\sb2$. The efficient growth at low CO$\sb2$ levels is a reflection of the CO$\sb2$ concentrating mechanism that is induced when cells are adapted to low CO$\sb2$ levels. In this dissertation, the effect of CO$\sb2$ on carbonic anhydrase and other proteins in C. reinhardtii is discussed. In the first part of the dissertation, the isolation and purification of a new isoenzyme of carbonic anhydrase is reported. This carbonic anhydrase is present when cells are grown in high CO$\sb2$ but absent in low CO$\sb2$. It is located …

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Collaborative Writing In Petroleum Engineering: A Case Study Of Petroleum Engineers In An Academic Setting, Michael Anne Coffey Aug 1993

Collaborative Writing In Petroleum Engineering: A Case Study Of Petroleum Engineers In An Academic Setting, Michael Anne Coffey

LSU Historical Dissertations and Theses

Interest in collaborative writing has surged in composition studies since the mid-tolate 1980s; aspects addressed include motivation, the composing process, the kinds of participants, authorship, conflict, etc. Much composition research concentrates on collaboration in the workplace to gain an understanding of collaborative writing that can be readily transferred to the classroom and that can prepare students for the social, as opposed to solitary, act of writing—to encourage collaborative thought. In this study, I attempted to find out more about what occurs in the stages (prewriting, writing, post-writing) of collaborative writing. My subjects were petroleum engineers on university campuses. Departments were …

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Mechanisms Of Crater Formation While Drilling A Well., Luiz Alberto Santos Rocha Jan 1993

Mechanisms Of Crater Formation While Drilling A Well., Luiz Alberto Santos Rocha

LSU Historical Dissertations and Theses

Current well control practice for land or bottom-supported marine rigs usually calls for shutting-in the well when a kick is detected if sufficient casing has been set to keep any flow underground. In addition, the working pressure of the casing and surface equipment is maintained high enough to insure that formation fracture occurs before a failure of these items. Even if high shut-in pressures are seen, an underground blowout is preferred over a surface blowout. On the other hand, an operator will put the well on a diverter if he believes that the casing is not set deep enough to …

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Use Of The History Of Science In A Nonscience Majors Course: Does It Affect Students' Understanding Of The Nature Of Science?, Linda Easley Roach Jan 1993

Use Of The History Of Science In A Nonscience Majors Course: Does It Affect Students' Understanding Of The Nature Of Science?, Linda Easley Roach

LSU Historical Dissertations and Theses

In response to a call for more research into using the history of science to teach the nature of science, a call for curriculum materials for inclusion of the nature of science in undergraduate nonscience majors courses, and in keeping with the nature of science described in the literature, interactive nature-of-science historical vignettes were utilized in a quantitative and qualitative investigation. Interactive nature-of-science historical vignettes employ the interrupted story form and binary opposites involving conflict to generate student participation and spark discussion about the nature of science. They were utilized as an experimental technique in a university level, introductory nonscience …

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Functional Morphology Of The Lingual Apparatus Of Sandgrouse (Aves: Pteroclidae)., Werner Muller Jan 1993

Functional Morphology Of The Lingual Apparatus Of Sandgrouse (Aves: Pteroclidae)., Werner Muller

LSU Historical Dissertations and Theses

The morphology of the lingual apparatus of three species of sandgrouse (Aves; Pteroclidae) has been described. All biomechanically important parts were included in the description, i.e., all muscles potentially involved in the functioning of the lingual apparatus, all skeletal parts, the salivary glands associated with the lingual apparatus, and the surface morphology of the oropharyngeal cavity. For each muscle its potential functions have been described. In a comparison with data from the literature of three other groups of birds it was found that the functional organization of the lingual apparatus of the sandgrouse is strikingly similar to the one found …

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Field Evaluation Of The Movement Of Agricultural Chemical Contaminants In Alluvial Soils With A Shallow Water Table., Orlino Agustin Mercado Jan 1993

Field Evaluation Of The Movement Of Agricultural Chemical Contaminants In Alluvial Soils With A Shallow Water Table., Orlino Agustin Mercado

LSU Historical Dissertations and Theses

The movement of agricultural chemical contaminants in alluvial soils with a shallow water table in a warm, humid environment was evaluated in this study. Bromide, a non-adsorbent tracer, was used to assess the pathways of water and solute in the soil profile. The movement and fate of three commonly used herbicides: Trifluralin, Metolachlor, and Metribuzin were determined. The data gathered from the herbicide study were used to compare with the results of simulation to validate the pesticide component of the GLEAMS model. The study was conducted at the Ben Hur Research Farm of the Louisiana Agricultural Experiment Station. Five relatively …

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Determinants Of Mangrove Species Distribution In Neotropical Forests: Biotic And Abiotic Factors Affecting Seedling Survival And Growth., Karen Lee Mckee Jan 1993

Determinants Of Mangrove Species Distribution In Neotropical Forests: Biotic And Abiotic Factors Affecting Seedling Survival And Growth., Karen Lee Mckee

LSU Historical Dissertations and Theses

Mangroves are salt-tolerant trees and shrubs that dominate the intertidal zone in many tropical and subtropical coastal regions. These intertidal forests often exhibit relatively distinct and recurring patterns of species distribution. A series of field and laboratory experiments examined biotic and abiotic factors affecting survival and growth of three neotropical mangrove species: Rhizophora mangle (red mangrove), Avicennia germinans (black mangrove), and Laguncularia racemosa (white mangrove). A field survey across a mangrove island range in Belize revealed six vegetation zones based on differences in dominant canopy species, size and vigor of the trees, spatial position relative to the shoreline, and hydro-edaphic …

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A Non-Proportional Cyclic Plasticity Model For Metals With Ratchetting Effects., Srinivasan Madras Sivakumar Jan 1993

A Non-Proportional Cyclic Plasticity Model For Metals With Ratchetting Effects., Srinivasan Madras Sivakumar

LSU Historical Dissertations and Theses

The path-dependent and nonlinear behavior of metallic materials subjected to cyclic loading is modelled using the proposed hardening rule. It uses mainly two surfaces, a yield and a limit surface and includes the memory effects through a separate surface called the memory surface which is obtained from a maximum stress criterion. The model considers the facts that the motion of the center of the yield surface in the stress space is mainly governed by the direction of the deviatoric stress rate and that the uniqueness of the solution requires nesting of the two surfaces. The model proposed satisfies both conditions …

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Soil Processes Related To Marsh Loss In Coastal Louisiana., John Andrew Nyman Jan 1993

Soil Processes Related To Marsh Loss In Coastal Louisiana., John Andrew Nyman

LSU Historical Dissertations and Theses

Marsh loss in Louisiana ($\sim$8,000 ha/yr) is attributed primarily to salt-water intrusion, flooding, and sediment starvation. Soil processes were studied to complement previous work identifying causes rather than mechanisms. Relationships between soil mineral and organic matter were examined to better understand accretion, which counters subsidence and sea-level rise. More soil volume was occupied by organic matter than mineral matter in fresh, intermediate, and brackish soil. Estimated mineral sediment requirements for accretion were 6.7 times greater in salt marsh than in fresh marsh. Sediment requirements probably increase seaward because of sulfate in seawater, reduction of sulfate to toxic sulfides in soil, …

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A Cross-Age Study Of Students' Knowledge Of Insect Metamorphosis: Insights Into Their Understanding Of Evolution., Mary Susan Nichols Jan 1993

A Cross-Age Study Of Students' Knowledge Of Insect Metamorphosis: Insights Into Their Understanding Of Evolution., Mary Susan Nichols

LSU Historical Dissertations and Theses

Insect metamorphosis is relatively easy to explain at a superficial level, but a deep understanding of the concept reveals a complex array of interrelationships, most importantly those that address evolution. This is significant because, in biology, evolution is considered to be a central theme. Participants for this study were selected from grades 5, 7, 9, and 11 according to low, middle, or high achievement levels in their science classes, and to scores on a national achievement test. The research incorporated a three-level response strategy in order to ascertain more completely students' knowledge of insect metamorphosis, and to better suggest how …

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Strongylus Vulgaris: Protection, Pathology And Humoral Immune Responses In The Immunized Pony., Clifton Michael Monahan Jan 1993

Strongylus Vulgaris: Protection, Pathology And Humoral Immune Responses In The Immunized Pony., Clifton Michael Monahan

LSU Historical Dissertations and Theses

Protective resistance to Strongylus vulgaris infection was examined by immunization of ponies with radiation-attenuated larvae or soluble parasite homogenates. Twelve yearling ponies raised and maintained under parasite-free conditions were divided into four groups which received either radiation-attenuated L$\sb3$; aqueous-soluble adult somatic antigens plus adjuvant; aqueous-soluble larval somatic antigens with excretory/secretory products and adjuvant; or media with adjuvant. Ponies were immunized twice; radiation-attenuated L$\sb3$ were administered orally and soluble antigens or control injections were given intramuscularly. Six weeks following the second immunization, ponies were challenged per os with virulent S. vulgaris L$\sb3.$ Ponies were monitored twice daily for rectal temperatures and …

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Acetylation Of Seaweed Alginate By Pseudomonas Syringae., Jin Woo Lee Jan 1993

Acetylation Of Seaweed Alginate By Pseudomonas Syringae., Jin Woo Lee

LSU Historical Dissertations and Theses

Acetylation of bacterial alginate by Pseudomonas syringae subsp. phaseolicola ATCC 19304 was independent of alginate biosynthesis. This allowed the development of a process for acetylating seaweed alginate using immobilized P. syringae ATCC 19304 cells. About 50% of the mannuronic acid residues of seaweed alginate were acetylated by carbon immobilized P. syringae cells in a fluidized bed, up-flow reactor system fed continuously with seaweed alginate and gluconic acid. O-Acetylation by this process was found to be specific for the C-2 and/or C-3 position(s) of mannuronate residues. Acetylated seaweed alginate showed altered properties including increased viscosity and changed affinities for some cations.

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Professional Competencies Needed By Extension Agents In The Louisiana Cooperative Extension Service., William Blaine Reynolds Jan 1993

Professional Competencies Needed By Extension Agents In The Louisiana Cooperative Extension Service., William Blaine Reynolds

LSU Historical Dissertations and Theses

The purpose of this study was to identify the professional competencies needed by the Cooperative Extension agents in Louisiana as perceived by extension agents. Additional purposes of the study were to identify when the respondents believed the identified competencies should be acquired and to describe the responding agents with regard to selected demographic variables. One-hundred forty-one professional competency items were included in a questionnaire that was divided into two parts. The competencies were divided into nine categories that were designed to measure participants' perceptions as to the importance of need for the competencies by extension agents. A five-point Likert-type scale …

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