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Illness Behavior And The Preoperative Prediction Of Postoperative Pain In Cholecystectomy Patients., Lannis Lee Tynes Jr Jan 1989

Illness Behavior And The Preoperative Prediction Of Postoperative Pain In Cholecystectomy Patients., Lannis Lee Tynes Jr

LSU Historical Dissertations and Theses

Eighty (80) elective cholecystectomy patients volunteered to participate in the present study which assessed the relation between past illness behavior and the report of pain following surgery. A review of the literature indicated that demographic variables (e.g., sex, age) and general psychological variables (e.g. state anxiety) have been the subject of many studies attempting to predict postoperative pain, yet learning and behavioral factors such as past illness behavior and familial modelling of illness behavior have not. Preoperative assessments included the Illness Behavior Inventory (IBI; Turkat, 1983), the Familial Illness Behavior Inventory (IBI-F; derived from the IBI), the State Trait Anxiety …

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The Lactate Threshold And Carbon Dioxide Flow To The Lung As Predictors Of Ventilation During Exercise., Becky Anne Baker Jan 1989

The Lactate Threshold And Carbon Dioxide Flow To The Lung As Predictors Of Ventilation During Exercise., Becky Anne Baker

LSU Historical Dissertations and Theses

Three studies were performed to determine the relationship between blood lactate, CO$\sb2$ flow to the lung, and ventilation during exercise. First, the method of determining the lactate threshold by use of log-log and semilog transformations developed by Beaver and his colleagues was modified to provide an objective method of determining the threshold which resulted in a significantly better fit (p $<$.05) of the log-log model to the data. Second, to test the theory that the increase in CO$\sb2$ flow to the lung due to bicarbonate buffering of H+ from lactic acid causes the rise in ventilation out of proportion to VO$\sb2$ at the ventilatory threshold, the lactate thresholds of these subjects were used to predict their ventilatory thresholds. The lactate threshold determined by the modified log-log model/method was a poor predictor with an insignificant relationship between the lactate and ventilatory thresholds (p $>$.05). In the third study, six subjects were tested during 4 sessions to determine the relationship between ventilation and CO$\sb2$ flow to the lung during exercise and also during rest and exercise while CO$\sb2$ was being inhaled. This relationship …

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The Relation Of Cognition, Emotion And Behavior To The Prediction Of Depressive Symptomatology In Referred And Nonreferred Adolescents., Tracy Lynn Cole Jan 1989

The Relation Of Cognition, Emotion And Behavior To The Prediction Of Depressive Symptomatology In Referred And Nonreferred Adolescents., Tracy Lynn Cole

LSU Historical Dissertations and Theses

Researchers have shown an increased interest in depression in children and adolescents in the last few years. As a result, a body of research exists which has focused on the cognitive and behavioral aspects of depression in children and adolescents. Few studies, however, have examined the relation of emotion to depression. Therefore, the purpose of this investigation was to examine the relation of cognition, emotion and behavior to depression. Eighty adolescents (nonreferred) from public schools in a southern city and seventy-three adolescents (emotionally disturbed) from a psychiatric facility in the same area participated in the study. Each adolescent completed self-report …

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Effects Of Cocaine Use And Withdrawal On Clinical Memory And New Learning., Madeline Uddo-Crane Jan 1989

Effects Of Cocaine Use And Withdrawal On Clinical Memory And New Learning., Madeline Uddo-Crane

LSU Historical Dissertations and Theses

This project was conceptualized as an exploratory examination of the neuropsychological sequelae of cocaine abuse, specifically the drug's effect on new learning and memory. The experimental groups were composed of 30 veterans enrolled in a drug treatment program for cocaine abuse. This group was divided equally by route of administration, i.e., group one included 15 individuals whose preferred route of administration was intravenous injection; group two included 15 individuals whose preferred route of administration was smoking. The comparison group consisted of 15 individuals enlisted in the National Guard. The groups were essentially homogeneous, with a mean age of 34.6 ($SD$ …

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The Relation Of Compliance To Quality Of Life In Dialysis Patients., Linda S. Dietz Jan 1989

The Relation Of Compliance To Quality Of Life In Dialysis Patients., Linda S. Dietz

LSU Historical Dissertations and Theses

The goal of the current study was to gain knowledge of the impact that dietary compliance has on quality of life for end-stage renal disease patients receiving chronic in-center hemodialysis. As a result of this type of research, health care professionals may better understand the individual and collective influence that various aspects of dietary compliance have on quality of life. This knowledge may be helpful in making future recommendations about the necessity of the dietary regimen. This study investigated the relation between three commonly employed physiological parameters of dietary compliance (blood urea nitrogen, potassium, and intersession weight gain) and four …

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Modeling, Simulation, And Automatic Control For Optimum Drying And Storage Of Rough Rice In A Bin System., Jong Hoon Chung Jan 1989

Modeling, Simulation, And Automatic Control For Optimum Drying And Storage Of Rough Rice In A Bin System., Jong Hoon Chung

LSU Historical Dissertations and Theses

A study on modeling, simulation, and automatic control for optimum drying and storage of rough rice in a farm-bin system was conducted to address some aspects of rice post-harvest technology. Resistance-type moisture sensors and temperature and humidity sensors were evaluated for continuously monitoring the conditions of air and grain. Models to predict rice moisture models during drying and storage were developed. Based on accuracy and predictability, the use of the capacitance-type humidity sensor is recommended over the resistance-type moisture sensor. A pressure drop model of airflow through rough rice was developed to aid in determining the optimum size and type …

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Dispersion And Physiological Ecology Of Mosquito Adults In Louisiana Ricelands., Alan Richard Holck Jan 1989

Dispersion And Physiological Ecology Of Mosquito Adults In Louisiana Ricelands., Alan Richard Holck

LSU Historical Dissertations and Theses

A sampling technique for estimating the size of adult mosquito populations in vegetation was developed. Regression analysis was used to obtain absolute density estimates from sweep net. Diurnal population size estimates of Louisiana riceland mosquitoes were made on a 35.6-square km site 5 km south of Kaplan, LA. Four mosquito species were present: Psorophora columbiae, Anopheles quadrimaculatus, An. crucians and Culex salinarius. Mosquito species were highly stratified in their distribution. Psorophora columbiae was primarily observed in pastures with livestock and in rice fields. Both Anophelines were found only in structures. Culex salinarius did not exhibit habitat preference. Anopheles quadrimaculatus exhibited …

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Agrobacterium Tumefaciens - Mediated Transfer Of Plant Dna For Gene Expression Analysis., Woo Sung Lee Jan 1989

Agrobacterium Tumefaciens - Mediated Transfer Of Plant Dna For Gene Expression Analysis., Woo Sung Lee

LSU Historical Dissertations and Theses

Agrobacterium tumefaciens causes crown gall tumor primarily in dicotyledonous plants. The infection mechanism reveals that a portion of bacterial DNA (T-DNA) is transferred into the plant nuclear genome. This transformation system is widely utilized in plant genetic engineering and plant molecular biology. In this dissertation, two experiments were carried out. First, the copy number, physical structure and F1 segregations of T-DNA copies were analyzed, attempting to understand the mode of T-DNA integration into the plant genome. While the mechanism of Agrobacterium response to plant signals and generation and transfer of T-DNA intermediates through actions of virulence genes is generally understood, …

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Factors Associated With The Production Of Export Quality Fruit By Small Banana Farmers Of The Rio Grande Valley, Portland, Jamaica., Terrence W. Thomas Jan 1989

Factors Associated With The Production Of Export Quality Fruit By Small Banana Farmers Of The Rio Grande Valley, Portland, Jamaica., Terrence W. Thomas

LSU Historical Dissertations and Theses

The study was aimed at determining the relationship between two production variables--technology use, and production of export quality fruit--of small banana farmers in the Rio Grande Valley, Jamaica and selected socioeconomic, personal characteristic and opinion variables, assessing the amount of variance in production explained by the latter, and identifying variables that moderate or mediate the relationship between production variables. The target population was 120 farmers selling bananas to a public boxing plant. A random sample of non-banana farmers was used as a cross-validation check to make inferences to all farmers. Farmers were personally interviewed using a pretested schedule. Stepwise multiple …

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Molecular Biological Studies On The Degradation Of Diphenyl Ethers By Bacteria., Hung-Ming James Liaw Jan 1989

Molecular Biological Studies On The Degradation Of Diphenyl Ethers By Bacteria., Hung-Ming James Liaw

LSU Historical Dissertations and Theses

Microbial degradation of diphenyl ethers was studied utilizing several different approaches. The first approach was to isolate mutants from a ligninolytic Erwinia sp. by conventional mutagenesis and selection. A copper-resistant mutant, designated as Erwinia sp. CU3614, was isolated and characterized to be capable of degrading diphenyl ethers as well as one dibenzo-p-dioxin in the presence of copper ions. Isolation of Tn5 transposon-induced mutants of Erwinia sp. CU3614, which lost degradation ability, demonstrated that in all probability a copper-associated activity in the biotransformation of aromatic ethers was involved. In order to study the degradation at the molecular biological level, a 2.1 …

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Ecological Consequences Of Variation In Pollinator Availability: Ocotillo, Carpenter Bees, And Hummingbirds In Two Deserts., Peter Evans Scott Jan 1989

Ecological Consequences Of Variation In Pollinator Availability: Ocotillo, Carpenter Bees, And Hummingbirds In Two Deserts., Peter Evans Scott

LSU Historical Dissertations and Theses

I studied the pollination ecology of a widespread desert shrub, ocotillo (Fouquieria splendens), and some of the consequences of geographic variation in availability of pollinators. I studied ocotillo in the Chihuahuan Desert of western Texas (Big Bend National Park) for three flowering seasons, and in the Sonoran Desert of southern California (Anza-Borrego Desert State Park) for parts of two flowering seasons. In both areas, ocotillo flowers profusely for one month each year, and requires outcross pollination to mature more than 5% of its potential seed crop. In Texas, carpenter bees (Xylocopa californica arizonensis) and their nest plants (species of Agave, …

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Avian Influenza Viruses In Coastal Louisiana Waterfowl: Host And Environmental Factors Affecting Prevalence And Viral Persistence., David Edward Stallknecht Jan 1989

Avian Influenza Viruses In Coastal Louisiana Waterfowl: Host And Environmental Factors Affecting Prevalence And Viral Persistence., David Edward Stallknecht

LSU Historical Dissertations and Theses

Cloacal and tracheal swabs were collected from 1,389 hunter-killed ducks in Cameron Parish, Louisiana during the 1986 and 1987 waterfowl seasons. These included 605 blue-winged teal (Anas discors), 75 mottled ducks (A. fulvigula), 375 gadwalls (A. strepera) and 334 green-winged teal (A. crecca). Twenty-eight avian influenza viruses (AIVs) were isolated. Prevalence estimates of AIV in ducks during September, November and December/January were 3.1%, 2.1%, and 0.4%, respectively. Differences in prevalence were detected by season ($P$ =.044) and age class ($P$ =.036). Two isolations from resident mottled ducks indicate local transmission of AIV on these wintering areas. Much subtype diversity was …

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The Impact Of Vertebrate Herbivores On Primary Production Of Sagittaria Marshes In The Wax Lake Delta, Atchafalaya Bay, Louisiana., Jenneke Maria Visser Jan 1989

The Impact Of Vertebrate Herbivores On Primary Production Of Sagittaria Marshes In The Wax Lake Delta, Atchafalaya Bay, Louisiana., Jenneke Maria Visser

LSU Historical Dissertations and Theses

Aboveground production of tidal freshwater marshes dominated by Sagittaria latifolia or Sagittaria platyphylla is best estimated with nondestructive techniques. A nondestructive method for estimation of Sagittaria aboveground biomass and production was developed using multiple regression. This technique yielded estimates of aboveground biomass of Sagittaria ranging from 0 to 1875 g/m$\sp2$; harvested aboveground biomass of Sagittaria ranged from 85 to 1356 g/m$\sp2$. Aboveground production was estimated nondestructively on the basis of permanent plots (465-3809 g/m$\sp2$/yr) and destructively on the basis of end-of-season biomass (775-4056 g/m$\sp2$/yr). Destructively estimated belowground production ranged from 233 to 1199 g/m$\sp2$/yr. Aboveground production was positively correlated with …

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Kinetics Of Chromate And Phosphate Sorption By Oxide Minerals And Soils., David S. Burden Jan 1989

Kinetics Of Chromate And Phosphate Sorption By Oxide Minerals And Soils., David S. Burden

LSU Historical Dissertations and Theses

A nonlinear multireaction model was used to describe kinetic retention data sets for chromate, phosphate, arsenate, borate, fluoride, molybdate, selenite, and silicate by goethite, an iron oxide mineral, and selected soils. These data sets were obtained from laboratory batch experiments with time up to 24 h. Either a three-parameter version of the model consisting of one nonlinear reversible and one first order irreversible reaction, or a five-parameter version consisting of two nonlinear reversible and one first order irreversible reactions was capable of predicting anion sorption by goethite. A mechanistic model consistent with the nonlinear multireaction approach was also proposed in …

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Geometric Modeling And Recognition Of Elongated Regions In Images., Charles Anthony Lipari Ii Jan 1989

Geometric Modeling And Recognition Of Elongated Regions In Images., Charles Anthony Lipari Ii

LSU Historical Dissertations and Theses

The goal of this research is the recovery of elongated shapes from patterns of local features extracted from images. A generic geometric model-based approach is developed based on general concepts of 2-d form and structure. This is an intermediate-level analysis that is computed from groupings and decompositions of related low-level features. Axial representations are used to describe the shapes of image objects having the property of elongatedness. Curve-fitting is shown to compute axial sequences of the points in an elongated cluster. Script-clustering is performed about a parametric smooth curve to extract elongated partitions of the data incorporating constraints of point …

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Fine Scale Velocity Measurements In A Turbulent Jet In A Confined Crossflow., Julie Ann Mathis Jan 1989

Fine Scale Velocity Measurements In A Turbulent Jet In A Confined Crossflow., Julie Ann Mathis

LSU Historical Dissertations and Theses

Measurements of the fine scale velocity field are made for a turbulent jet in a confined crossflow. With a crossflow velocity of 10.0 m/sec, jet-to-crossflow velocity ratios of 1, 2 and 4 are examined. Velocity measurements are obtained by laser velocimetry. The velocimetry system consists of a 15mW laser with a fringe mode optics setup, operated in the backscatter mode. Signal processing is accomplished with a tracker processer. At each measuring location, 28,400 velocity readings are obtained at a sampling frequency of 38,460 sec$\sp{-1}$. Calculations include construction of autocorrelation functions, Kolmogorov-normalized energy spectra and their moments, skewness and flatness of …

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Biology And Control Of Strawberry Anthracnose Crown Rot And Fungicidal Control Of Strawberry Fruit Rots., Thomas Bond Mcinnes Jan 1989

Biology And Control Of Strawberry Anthracnose Crown Rot And Fungicidal Control Of Strawberry Fruit Rots., Thomas Bond Mcinnes

LSU Historical Dissertations and Theses

Surveys of strawberry (Fragaria x ananassa Duch.) summer nursery beds and production fields in Louisiana from 1986-1989 indicated that anthracnose crown rot (ACR) incited by Colletotrichum fragariae Brooks limited both plant and fruit production on most farms. Pathogen-free production plants were provided to growers in the strawberry growing region of southeast Louisiana for establishment of summer nursery beds. The pathogen-free strawberry plants remained free of ACR in summer nursery beds separated from beds with locally grown transplants. Infield spread of ACR was rapid in summer nursery beds, but there was no evidence of disease spread in production fields. To assay …

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The Affective Variant Hypothesis: How Is Bulimia Nervosa Related To Depression?, Rita C. Prather Jan 1989

The Affective Variant Hypothesis: How Is Bulimia Nervosa Related To Depression?, Rita C. Prather

LSU Historical Dissertations and Theses

Bulimia nervosa patients frequently score from mild to severe on measures of depressive symptoms. This association between bulimia nervosa and depression led some researchers to hypothesize that bulimia nervosa is a variant of the affective disorder of depression. The main purpose of this study was to provide further evaluation of the affective variant hypothesis of bulimia nervosa. It was postulated that bulimia nervosa patients with and without depression would differ from each other and from depressives without eating disorders on specific measures of cognitive, behavioral, and somatic symptoms associated with depression. Secondly, it was hypothesized that the nondepressed and depressed …

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Spectroscopic Studies Of Biological And Synthetic Tetranuclear Iron-Sulfur Clusters., Yvonne Amalia Onate Jan 1989

Spectroscopic Studies Of Biological And Synthetic Tetranuclear Iron-Sulfur Clusters., Yvonne Amalia Onate

LSU Historical Dissertations and Theses

Room-temperature UV-visible adsorption, low-temperature magnetic circular dichroism (MCD), electron paramagnetic resonance (EPR), and resonance Raman (RR) spectroscopies have been used to characterize the electronic, magnetic and structural properties of the (4Fe-4S) centers in Azotobacter vinelandii Fe proteins from Mo- and V-nitrogenases (Av2 and Av2$\sp\prime$, respectively), and Bacillus subtilis glutamine phosphoribosylpyrophosphate amidotransferase. These studies have characterized the S = 1/2 and S = 3/2 forms of the (4Fe-4S) $\sp{1+}$ cluster in native Av2 and Av2$\sp\prime$ in the presence and absence of the protein unfold agent urea, glassing solvents, such as ethylene glycol and glycerol, and nucleotides, such as ATP. The results …

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Phosphatidylethanolamine Synthesis By A Base Exchange Reaction In Castor Bean Endosperm., Sungho Shin Jan 1989

Phosphatidylethanolamine Synthesis By A Base Exchange Reaction In Castor Bean Endosperm., Sungho Shin

LSU Historical Dissertations and Theses

An ethanolamine base exchange enzyme has been assayed in the endoplasmic reticulum (ER) of castor bean (Ricinus communis L. var. Hale) endosperm. The activity was maximal at ethanolamine concentrations of 30 uM in the presence of 2 mM CaCl$\sb2$. The optimum pH was 7.8 using HEPES buffer. Under these conditions, the enzyme had a maximum enzyme velocity of approximately 0.3 nmol h$\sp{-1}$ mg$\sp{-1}$ protein and an apparent Km of 5.0 uM for ethanolamine. A maximum velocity of approximately 1.7 nmol h$\sp{-1}$ mg$\sp{-1}$ protein was obtained under similar conditions with L-serine at about 400 uM in a serine base exchange reaction. …

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The Evolution Of Igg And Igm Antibodies To Antigens Of Mycobacterium Leprae In Experimentally Inoculated Armadillos., Abdul Reza Vadiee Jan 1989

The Evolution Of Igg And Igm Antibodies To Antigens Of Mycobacterium Leprae In Experimentally Inoculated Armadillos., Abdul Reza Vadiee

LSU Historical Dissertations and Theses

The nine-banded armadillo (Dasypus novencinctus linn.) is highly susceptible to infection with M. leprae and has become an important animal model in the study of leprosy. In an attempt to define the major immunogens of M. leprae and the isotypic antibody response to these molecules during infection, the IgG and IgM antibody responses of experimentally-infected armadillos to the sonicated M. leprae, supernatant fraction of sonicated M. leprae, lipoarabinomannan derived from M. tuberculosis, and phenolic glycoliopid-I was analyzed using immunoblot and ELISA. Antibodies to the specific epitope (defined by monoclonal antibody IIIE9) on the 65-kDa protein of M. leprae were analyzed …

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Lsu General Catalog 1989-1990, Louisiana State University And Agricultural And Mechanical College Jan 1989

Lsu General Catalog 1989-1990, Louisiana State University And Agricultural And Mechanical College

LSU General Catalog

The LSU General Catalog describes all undergraduate and graduate departments and programs with degree requirements and courses offered for each one. The General Catalog includes information on registration and financial aid as well as academic services offered to all students.

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Studies On Trypanosoma Cruzi Isolates From Louisiana Mammals With Particular Reference To Infectivity To Dogs., Stephen Charles Barr Jan 1989

Studies On Trypanosoma Cruzi Isolates From Louisiana Mammals With Particular Reference To Infectivity To Dogs., Stephen Charles Barr

LSU Historical Dissertations and Theses

This dissertation describes studies on three Trypanosoma cruzi isolates from Louisiana mammals with particular reference to infectivity to dogs. Isolates from an opossum (Tc-O) and armadillo (Tc-A) were obtained during a blood culture survey of these animal populations in Louisiana. Prevalence of T. cruzi were 37.5% and 1% in opossums and armadillos respectively. Further, 48% opossums had myocarditis suggestive of T. cruzi infection. Rural dogs with known contact with T. cruzi hosts, housed rural dogs, urban animal shelter dogs and household pets showed 4.7, 0, 2.3 and 0% serological prevalence to T. cruzi respectively. Tc-O and Tc-A (wild isolates) displayed …

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Isolation, Characterization, And Symbiotic Effectiveness In Soybeans Of Exopolysaccharide Mutants Of Rhizobium Fredii Usda191., Young Hwan Ko Jan 1989

Isolation, Characterization, And Symbiotic Effectiveness In Soybeans Of Exopolysaccharide Mutants Of Rhizobium Fredii Usda191., Young Hwan Ko

LSU Historical Dissertations and Theses

Chapter 1. Production of exopolysaccharides by Rhizobium has been linked with efficient invasion and nodulation of leguminous plant roots by the bacteria. Exopolysaccharide-deficient (exo) mutants of Rhizobium fredii USDA191 were isolated by Tn5-insertion mutagenesis. Five phenotypically unique exo mutants were investigated for exopolysaccharide synthesis and their ability to nodulate soybeans. The exopolysaccharides produced by these mutants were analyzed for polysaccharide composition by column chromatography and thin layer chromatography. Two mutants designated exo3 and exo5 were deficient in both the neutral glucan and exopolysaccharide synthesis, but still made effective nodules on Glycine max cv. Peking, although with decreased efficiency. The remaining …

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The Reproductive Ecology And Population Biology Of The Puerto Rican Nightjar Caprimulgus Noctitherus., Francisco Jose Vilella Jan 1989

The Reproductive Ecology And Population Biology Of The Puerto Rican Nightjar Caprimulgus Noctitherus., Francisco Jose Vilella

LSU Historical Dissertations and Theses

The reproductive ecology and population biology of the Puerto Rican Nightjar (Caprimulgus noctitherus), and population biology of the small Indian mongoose (Herpestes auropunctatus) were studied in Puerto Rico from 1985-1987. Six areas in Puerto Rico were selected to determine geographic distribution and estimate density. Nightjar presence was initially detected by using playback recordings; density was estimated using fixed-width transect call counts. Three areas located in northern moist limestone forest had no relict nightjars. Nightjars were found in three areas located in southwestern Puerto Rico. A total of 676 nightjars were recorded in 9,838.7 ha surveyed. These were distributed among three …

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The Structural And Functional Roles Of Critical Amino Acid Residues In Drosophila Alcohol Dehydrogenase., Zhuo Chen Jan 1989

The Structural And Functional Roles Of Critical Amino Acid Residues In Drosophila Alcohol Dehydrogenase., Zhuo Chen

LSU Historical Dissertations and Theses

Alcohol dehydrogenase (ADH, alcohol:NAD oxidoreductase, EC1.1.1.1) from Drosophila melanogaster (DmADH) is unique among alcohol dehydrogenases in metal ion requirement, substrate preference, and stereospecificity of hydride transfer. In order to study this unique enzyme, the first part of this dissertation reports the construction and expression of DmADH cDNA in E. coli hosts. The second part of the dissertation shows the structural function of glycine-14 in putative NAD-binding domain of DmADH. The comparison of DmADH to horse liver ADH suggests that glycine-14 in DmADH is located at the first position of a "conserved sequence" which maintains the tight turn structure positioned in …

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Marsh:Water Column Interactions In Two Louisiana Estuaries. Flux Measurements And Conceptual Implications., Daniel Louis Childers Jan 1989

Marsh:Water Column Interactions In Two Louisiana Estuaries. Flux Measurements And Conceptual Implications., Daniel Louis Childers

LSU Historical Dissertations and Theses

Many important ecosystem-level processes are integrated in hydrologically-forced marsh:water column interactions in estuaries. In this work, I quantified nutrient and sediment fluxes in two Louisiana estuaries using throughflow marsh flumes. The Barataria Basin estuary is in an later, deteriorating stage of the deltaic cycle. Brackish and saline marshes here exported dissolved inorganic nitrogen (DIN), total nitrogen, and dissolved organics (DOM); phosphorus fluxes were low and variable. Fourleague Bay marshes, in a earlier developmental stage of the deltaic cycle, imported DIN in the spring and released DIN in summer and fall. In this way, marshes here buffer open-bay N concentrations from …

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Toward The Inclusion Of Environmental Factors In The Concept And Measure Of National Income., George Edward Foy Jr Jan 1989

Toward The Inclusion Of Environmental Factors In The Concept And Measure Of National Income., George Edward Foy Jr

LSU Historical Dissertations and Theses

This dissertation uses Sir John Hicks' concept of income as a guide to integrate environmental factors into the concept and measure of national income. Chapter 1 introduces Hicks' concept of income as the maximum amount which one can consume in a given period and still be as well off at the end of the period as he was at the beginning. This basic idea of sustainability requires accounting for the net depletion of all capital consumed in current production. Chapter 2 documents recent trends in natural resource use to demonstrate that exclusion of the depreciation of environmental capital from NNP …

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Factors Affecting Trace Metal Mobility In Subsoils., Janice Kotuby-Amacher Jan 1989

Factors Affecting Trace Metal Mobility In Subsoils., Janice Kotuby-Amacher

LSU Historical Dissertations and Theses

The transport of metals to groundwater below hazardous waste sites is of great environmental concern. The movement of a particular metal is determined by (1) the soil's chemical and physical properties, (2) the amount and form of the metal, and (3) the composition of the soil or waste solution with which the metal is associated. Field and laboratory studies were conducted to examine these factors affecting metal mobility in subsoils. The objectives of the field studies were to determine the distribution and chemical forms of metal contaminants in subsoil at sites with known or suspected potential for groundwater contamination. The …

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Induction Of Polyploidy In Ictalurid Catfish And Comparative Performance Of Diploid And Triploid Channel Catfish And Channel X Blue Catfish Hybrids., Craig Gustaf Lilyestrom Jan 1989

Induction Of Polyploidy In Ictalurid Catfish And Comparative Performance Of Diploid And Triploid Channel Catfish And Channel X Blue Catfish Hybrids., Craig Gustaf Lilyestrom

LSU Historical Dissertations and Theses

This study provided indications of the feasibility of inducing polyploidy in ictalurids (channel catfish, Ictalurus punctatus, and hybrids with blue catfish, I. furcatus) by temperature or hydrostatic pressure shocks as well as the potential for improvement of growth and processing traits in triploid channel catfish x blue catfish hybrids. One-cell embryos of ictalurid catfish were subjected to either temperature or hydrostatic pressure shocks for induction of triploidy or tetraploidy. Hatch rates of embryos treated for induction of tetraploidy with hydrostatic pressure shocks were lower than those treated for induction of tetraploidy with heat shocks. Hatch rates of embryos tested for …

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