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Articles 37681 - 37710 of 39281
Full-Text Articles in Entire DC Network
Vegetational Stabilization Of Uranium Spoil Areas, Grants, New Mexico, Nathan Edmund Kelley
Vegetational Stabilization Of Uranium Spoil Areas, Grants, New Mexico, Nathan Edmund Kelley
Biology ETDs
Factors that could be detrimental to vegetative stabilization of uranium mine and mill waste material were examined. Physical and chemical analyses of materials from an open-pit uranium mine and material from three inactive mill tailing piles in New Mexico were performed. Analyses for selected trace elements in mill tailing material and associated vegetation from piles in New Mexico, Colorado, and Utah were also performed. Field and laboratory experiments identified problems associated with establishing vegetation on spoil material. Problems of uptake and concentration of toxic elements by plants growing on specific spoil material were also identified.
Ecological observations in conjunction with …
Dose Patterns For ¹⁰⁶Ruo₄ Inhaled By Fischer-344 Rats, Gene E. Runkle
Dose Patterns For ¹⁰⁶Ruo₄ Inhaled By Fischer-344 Rats, Gene E. Runkle
Biology ETDs
Ruthenium-106 is an abundant fission product radionuclide in the nuclear fuel cycle which has potential for release as ruthenium tetroxide. This study was designed to provide additional data needed to adequately assess the risk for humans potentially exposed to 106RuO4vapor. Fiscner-344 rats were given a nose-only exposure to 106RuO4 vapor to determine its distribution and retention patterns. The largest percentage of the initial body burden was found in the nasopharyngeal region of the respiratory tract. Ruthenium-106 deposited in this region was rapidly cleared and excreted in the feces. Less than 1% of the initial body …
The Influence Of Food On Induction Of Males In Daphnia Pulex, Paul Henry Schreuder
The Influence Of Food On Induction Of Males In Daphnia Pulex, Paul Henry Schreuder
Masters Theses
Introduction
Daphnia pulex Leydig (Crustacea, Cladocera) is a common component of the zooplankton of freshwater lakes and ponds. Its importance in the aquatic trophic structure as food for small fish has long been recognized.
Typical populations of daphnia consist almost exclusively of females. Under favorable conditions this situation is perpetuated by parthenogenetic reproduction. Eggs produced in this manner are referred to as parthenogenetic or summer eggs. When stressed by falling temperatures, drought, overpopulation, or starvation, populations shift to sexual.reproduction. Parthenogenetic eggs are produced which develop into males. Other eggs known as ephippial or winter eggs are also produced, which after …
A Comparative Study Of The Myosin Light Chain Kinases From Myoblast And Muscle Sources. Studies On The Kinases From Proliferative Rat Myoblasts In Culture, Rat Thigh Muscle, And Rabbit Skeletal Muscle, S. P. Scordilis, R. S. Adelstein
A Comparative Study Of The Myosin Light Chain Kinases From Myoblast And Muscle Sources. Studies On The Kinases From Proliferative Rat Myoblasts In Culture, Rat Thigh Muscle, And Rabbit Skeletal Muscle, S. P. Scordilis, R. S. Adelstein
Biological Sciences: Faculty Publications
Myosin light chain kinases have been isolated from rat thigh and rabbit skeletal muscle and cultured rat myoblasts. From these preparations, two types of kinases can be distinguished: calcium-dependent and calcium-independent. Both types of kinases can phosphorylate isolated P-light chains of myosin from several sources (skeletal muscle, cardiac muscle, and platelet). Data are shown which support the phosphorylation of the same site on the non-muscle P-light chains by both types of kinases. The rates of these reactions are, however, different for the two types of kinases. Kinetic analysis of the myoblast kinase show differing affinities for various P-light chains (non-muscle …
An Investigation Of Nitrogen Utilization As A Factor In The Size Selective Feeding Habits Of Lepomis Macrochirus, Stephen M. Hinckley
An Investigation Of Nitrogen Utilization As A Factor In The Size Selective Feeding Habits Of Lepomis Macrochirus, Stephen M. Hinckley
Masters Theses
No abstract provided.
Chromosome Behavior And Cytokinesis Of Nezara Sp. And Lygaeus Sp., Mohamed Barka Marwan
Chromosome Behavior And Cytokinesis Of Nezara Sp. And Lygaeus Sp., Mohamed Barka Marwan
Masters Theses
No abstract provided.
The Distribution And Abundance Of Tubificids In The Little Calumet River, Gladys Moreno
The Distribution And Abundance Of Tubificids In The Little Calumet River, Gladys Moreno
Masters Theses
No abstract provided.
Resource Use, Habitat Selection, And Seasonal Activity Of A Chihuahuan Snake Community, Robert Paul Reynolds
Resource Use, Habitat Selection, And Seasonal Activity Of A Chihuahuan Snake Community, Robert Paul Reynolds
Biology ETDs
Food habits and habitat selection were investigated in a snake community 1n northeastern Chihuahua, Mexico, from 1975 to 1977. A total of 418 snakes (20 species) was collected along Highway 16 from Villa Aldama to El Pastor. Examination of snake capture sites for the plant species present, and a study of structural characteristics of the vegetation and topographic features showed that snakes exhibited distinct habitat preferences. Rodent species present and their relative densities were assessed by 5400 trap nights at 18 trap stations.
Digestive tracts of 351 snakes of 16 species were examined and they yielded 153 food items. Rodents …
A Floristic Assessment Of The Datil Mountains, Reggie A. Fletcher
A Floristic Assessment Of The Datil Mountains, Reggie A. Fletcher
Biology ETDs
The Datil Mountains of west-central New Mexico were selected for a floristic inventory and analysis because of the lack of previous study in this section of the state. The location of the study area in relationship to the Basin and Range, Southern Rocky Mountain, and Colorado Plateau physiographic provinces was a major factor in determining the initial need for floristic work in the Datil Mountain area. An annotated checklist of the vascular flora of the study area was compiled. For those 590 collected taxa, available information was compiled which could serve as a useful tool for land management in this …
The Effect Of Developmental Temperature On Morphology, Energy Metabolism, Growth Hormone And Thyroid Stimulating Hormone In Long-Evans Rats, Dana Elizabeth Quinn
The Effect Of Developmental Temperature On Morphology, Energy Metabolism, Growth Hormone And Thyroid Stimulating Hormone In Long-Evans Rats, Dana Elizabeth Quinn
Dissertations and Theses
Long-Evans rats were raised from birth to eight weeks of age at 5°C, 20°C and 30°C. Blood was taken from animals two to eight weeks of age and assayed for growth hormone and thyroid stimulating hormone. The 30°C reared rats were found to have the longest ear, tail and hind limbs, followed by the 20°C reared rats. The 5°C rats were found to have the shortest ear, tail and hind limb. The 30°C and 5°C reared rats were found to have similar masses at the termination of the experiment. The 20°C reared rats had the smallest mass. Differences in size …
Ultrastructural Observations On The Cuticle Of The Desert Millipede, Orthoporus Ornatus (Girard) (Spirostreptidae): Effects Of Seasonality, Bound-Lipid Localization And Dri-Die 67 And Chloroform-Methanol Treatments, Leola Walker
Biology ETDs
In order to determine the effects of seasonality, bound-lipid localization, and treatments of Dri-die 67 and chloroform-methanol on the cuticular morphology of the desert millipede, Orthoporus ornatus, specimens collected west of Albuquerque in 1976-1977 were exposed to several experimental techniques. Because the dense nature of the cuticle presented difficulties in sectioning, a slightly modified procedure involving a vacuum oven was used in all experiments. A relatively standard procedure involving glutaraldehyde as a fixative and osmium tetroxide as a post-fixative was utilized in the descriptive and seasonal study. The method of Wigglesworth (1975a) was utilized in attempting to localize presumably protein-bound …
Immunization And Infection Of Rhesus Monkeys With Plasmodium Knowlesi: Evaluation Of Assays For Immunity, Robert Charles Jost
Immunization And Infection Of Rhesus Monkeys With Plasmodium Knowlesi: Evaluation Of Assays For Immunity, Robert Charles Jost
Biology ETDs
This study was done to test the efficacy of 3 malarial vaccine preparations using merozoite, schizont, and French press antigens (Ags). The experiment utilized the Plasmodium knowlesi - rhesus monkey system. In conjunction with this study the lymphocyte transformation test and the solid phase radioimmunoassay (RIA) were evaluated as in vitro assays for protective cell-mediated and humoral immune responses, respectively. Delayed dermal hypersensitivity reactions to P. knowlesi and the proportion of B and T lymphocytes were also examined by rosette formation. Lymphocytes from Ag-immunized monkeys showed greater in vitro blastogenic responses to P. knowlesi French press Ag than did lymphocytes …
Ua77/1 Western Alumnus, Vol. 49, No. 6, Wku Alumni Association
Ua77/1 Western Alumnus, Vol. 49, No. 6, Wku Alumni Association
WKU Administration Documents
Alumni magazine published by WKU. This issue has the following articles:
- Dero Downing Steps Down
- Douglas, Michele. Top Banana – Gary Riggs
- Egan, Sherry. WKU State Climatic Center
- Gibson, Debbie. I Kind of Believe It’s a Gift – Burt Feintuch, Folk Music
- New on the Gridiron
- Adams, Bob. Digital Voltmeter – Engineering Technology
- Schock, Jack. The Projectile Point – Archaeology
- Armstrong, Bryan. Confessions of a Journalism Intern
- Highland, Jim. Terry Climer
- Beauchamp, Donnie. Commonplace Things – Photography
- Miller, Richard. The Exceptional Student – Psychology, Biology
- Harry Snyder Speaks at Commencement
- Douglas, Michele. Students Take Advantage of Study Trips Abroad
- Western …
A Comparative Study Of Growth And Survival In Nestling Mockingbirds And Brown Thrashers, Bette J. Schardien
A Comparative Study Of Growth And Survival In Nestling Mockingbirds And Brown Thrashers, Bette J. Schardien
Retrospective Theses and Dissertations
No abstract provided.
A Study Of Lymphocyte Subpopulations In Allergic And Asthmatic Patients, Cleora W. Barnwell
A Study Of Lymphocyte Subpopulations In Allergic And Asthmatic Patients, Cleora W. Barnwell
Retrospective Theses and Dissertations
The role of T and B lymphocytes in the human immune response has been studied in allergic and asthmatic patients by many investigators. Theories of suppressed cellular immunity have been reported showing decreased levels of T cells in peripheral blood. Elevated levels of IgE, an antibody, have been reported in these conditions, but not shown to be significant in distinguishing the different types of asthma. A double blind study of 19 allergic and 42 asthmatic individuals was conducted measuring T and B cell levels and IgE levels. The asthmatic group was subdivided into three types, intrinsic, extrinsic and mixed. The …
Annotated Checklist Of The Flowering Plants Of South Padre Island, Texas, Robert I. Lonard, Frank W. Judd, Sammie L. Sides
Annotated Checklist Of The Flowering Plants Of South Padre Island, Texas, Robert I. Lonard, Frank W. Judd, Sammie L. Sides
School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)
This study catalogues the flowering plants of South Padre Island, Texas. A total of 207 species in 47 families is listed. The abundance and ecological distribution of each taxon are noted. Comparisons are made with the flora of Mustang Island, Texas. Ninety-three species, 96 genera and 36 families are common to both islands. Three families, Compositae, Gramineae and Leguminosae, contain large shares of the total number of species on both islands. Apparently, much of the floral diversity is due to the presence of a large number of species that are represented by small populations.
Synergistic Effects Of Wavelengths Of Ultraviolet Radiation On Capacity In A Mammalian Cell-Virus System In Vitro, Bobby Cobb
Masters Theses & Specialist Projects
The synergistic effect between each of two minor contaminating UV wavelengths has been studied. The TC-7 host cell-capacity system was used. The macromolecular damage induced in monolayers of cell cultures as the result of exposure to UV radiation was measured by determining the ability of irradiated cells to support the replication of Herpes simplex virus. The macromolecule involved has been shown to be DNA and the damage is probably due to the formation of thymine dimers plus some undefined chromosphore associated with the DNA of the cell.
Preliminary experiments showed that low exposures of germicidal radiation are less effective in …
The Effect Of Parental Bone Marrow & Spleen Cells In The Induction Of The Graft-Versus-Host Reaction, Ronald Grane
The Effect Of Parental Bone Marrow & Spleen Cells In The Induction Of The Graft-Versus-Host Reaction, Ronald Grane
Masters Theses & Specialist Projects
Variously aged (C57BL X C3H)F1 hybrid mice were used as recipients in experiments to determine if spleen or bone marrow cells from normal C57BL or C3H donors, spleen or bone marrow cells from C57BL donors previously treated with cortisone, or C57BL bone marrow cells previously incubated with serum from X-irradiated C57BL mice could induce a graft-versus-host reaction (GVHR).
The mice were assayed for GVHR by mortality or splenomegaly as detected by the discriminant spleen assay developed by Simonsen. Results show that spleen cells from normal C57BL, normal C3H, or cortisone-treated C57BL mice are capable of inducing a GVHR in …
The Role Of Seed Morphology In Identification Of Archeological Remains, Paul J. Knight
The Role Of Seed Morphology In Identification Of Archeological Remains, Paul J. Knight
Biology ETDs
In the last century, archeologists working in the southwestern United States and in other localities around the world have uncovered a sufficient quantity and diversity of archeological-botanical materials to warrant serious investigation of these materials as a source of data on the subsistence of prehistoric populations.
The Distribution And Zoogeography Of The Mammals Of Sonora, Mexico, William Caire
The Distribution And Zoogeography Of The Mammals Of Sonora, Mexico, William Caire
Biology ETDs
A distributional and zoogeographical analysis based on published records and approximately 13,000 specimens is provided for the 122 naturally occurring mammalian species in Sonora, Mexico. Twenty-eight species of unverified occurrence which could be present in Sonora are discussed. Domesticated mammals are listed and introduced species are briefly discussed. Descriptions of the topography, climate, vegetation, and hydrological features of Sonora are included. Dichotomous keys provide for the identification of Sonoran mammals to the levels of order, family, and species. Species accounts include the following: scientific and common names, additional identification remarks, general distributional discussions, various ecological and biological remarks, records of …
A Survey Of Nine Common Laboratory Compounds As Causative Agents Of Ciliostasis In Tracheal Explants From Mice, Josie Marshall Fletcher
A Survey Of Nine Common Laboratory Compounds As Causative Agents Of Ciliostasis In Tracheal Explants From Mice, Josie Marshall Fletcher
Masters Theses
No abstract provided.
An Ultrastructural Study Of Intramuscular Melanocytes In Pet/Wmr Mice, Charles August Gomer
An Ultrastructural Study Of Intramuscular Melanocytes In Pet/Wmr Mice, Charles August Gomer
Master's Theses
An examination of the lateral head of the gastrocnemius of the PET/Wn!.r mouse was made with an electron microscope. Cells of the perimysium and endomysium were described and the relationship of these cells to muscle cells was characterized. The relationship between melanocytes and muscle cells found in this strain was the major focus. Melanocytes were seen to be present in the perimysium and endomysium with the greatest concentration in the endomysium. Melanocytes of the perimysium appeared segregated from the adjacent tissue by fibroblasts,which surround ed the melanocytes with their cytoplasmic processes, a well as by collagen fibers. Melanocytes of the …
The Quality Of Storm Runoff From Different Kinds Of Land Surfaces In The Drainage Basin Of Westhampton Lake, Richmond, Virginia, Margaret Emil Coppedge
The Quality Of Storm Runoff From Different Kinds Of Land Surfaces In The Drainage Basin Of Westhampton Lake, Richmond, Virginia, Margaret Emil Coppedge
Master's Theses
Samples of runoff were collected during storms from four different areas within the drainage basin of Westhampton Lake, Richmond, Virginia, between October, 1977, and January, 1978. The areas were a residential area, concrete street gutter, asphalt parking lot, and broadleaf forest.
The samples were analyzed for pH, levels of reactive phosphate, nitrate, and turbidity, and their effects on the growth of algae from Westhampton Lake.
The pH of runoff from the residential area, gutter, and forest usually ranged between 6-7 and the parking lot usually ranged between 4-5. Levels of turbidity varied considerably between storms and areas. Runoff from the …
Lactate Dehydrogenase Isozyme Patterns From Five Species Of Snakes : Comparison Of Rattlesnake Vibratory Muscle With Body Epaxial Muscle, Cecil Bernard Cross
Lactate Dehydrogenase Isozyme Patterns From Five Species Of Snakes : Comparison Of Rattlesnake Vibratory Muscle With Body Epaxial Muscle, Cecil Bernard Cross
Master's Theses
Lactate dehydrogenase (LDH) isozyme patterns of seven tissues in each of five species of snakes are described from their polyacrylamide gel electrophoretic characteristics. The tissues examined included vibratory tail muscle, non vibratory tail muscle, body epaxial muscle, heart muscle, whole blood, liver and kidney. The species of snakes included Crotalus adamanteus, C. h. horridus, Agkistrodon piscivorus and Sistrurus miliarius barbouri from the family Crotalidae and Natrix taxispilota from the family Colubridae. These snakes show a decreasing continuum of tail vibratory activity, respectively, to N. taxispilota, which has a nonvibratory tail muscle.
Crotalus adamanteus, C. h. horridus and A. piscivorus have …
Germination, Respiration And Photosynthesis In Seeds Of Dwarf Mistletoe (Arceuthobium), Steven Wayne Gustafson
Germination, Respiration And Photosynthesis In Seeds Of Dwarf Mistletoe (Arceuthobium), Steven Wayne Gustafson
Dissertations and Theses
Germination, respiration, and photosynthesis in seeds of dwarf mistletoe (Arceuthobium) were studied. The effects of 1 hour soakings of seeds in aqueous solutions of 1, 2, or 3% H2O2 or 1, 2, 3, 4, or 5% Chlorox on germination of seeds were tested. Germination rates for seeds from three consecutive years (1975-1977) were obtained. Germination rates varied widely. This variance transcended subtle changes in treatment. Pretreatment of seeds with Chlorox resulted in significantly lower germination rates than those of the control. Chlorophyll concentrations were determined for seeds and aerial shoot tissue of four species. Seeds …
Clustering Of Phenotypic Variables And Construction Of An Identification Scheme For Human Isolates Of Haemophilus, Lynne Alice Johnson
Clustering Of Phenotypic Variables And Construction Of An Identification Scheme For Human Isolates Of Haemophilus, Lynne Alice Johnson
Biology ETDs
The taxonomy of the genus Haemophilus has been in a state of confusion for many years. As a result, laboratory identification of haemophili has been difficult, if not impossible. Due to the considerable pathogenicity of some members of the genus, it was felt that an accurate method of identification of those organisms was needed. This study has attempted to create a practical identification scheme for haemophili isolated in the clinical laboratory. A collection of 220 isolates from clinical laboratories was subjected to 35 biochemical and physiological tests and the data posted to a random matrix. The 7700 bits (220 X …
Effects Of Inorganic Ions On The Catalytic Activity Of Pig Liver Phosphofructokinase, Lawrence Gregory Foe
Effects Of Inorganic Ions On The Catalytic Activity Of Pig Liver Phosphofructokinase, Lawrence Gregory Foe
Biology ETDs
The effects of inorganic ions on the catalytic activity of pig liver phosphofructokinase were investigated. High concentrations of monovalent anions inhibit the enzyme by decreasing max with little change in the Hill coefficient. The efficiency of inhibition follows the
series NO3- < Cl- < ClO3- = Br- < I- < SCN-, which is similar to the classical Hofmeister series. Low concentrations (< 2 mM) of the divalent anions Pi, sO4 2-, s2O3 2- SO32- , and MoO42- all activate the enzyme by changing the kinetics from sigmoidal to hyperbolic, with no change in V max . However, B4o72- has no effect. The apparent dissociation constants of the activating anions for the enzyme were calculated from activation curves for the anions at 0.5mM ATP and 1.0m MF6p.The activation curve for so4-2 is sigmoidal; the activation curves for the other activating anions are hyperbolic. The monovalent cations K+, NH4+ , and Rb+ activate the enzyme by increasing V max without greatly affecting the Hill coefficient.
However, the [S}0.5 for F6P is decreased by these cations to an extent directly proportional to their ionic volumes.
The monovalent cations Li + , Na+ , and C s + have no activating effect; instead, high concentrations of these cations inhibit the enzyme in a manner similar to the monovalent anions. The efficiency of inhibition follows the series …
Membrane Potentials And Resistances Of Giant Mitochondria: Metabolic Dependence And The Effects Of Valinomycin, Bruce L. Maloff, Stylianos P. Scordilis, Christopher Reynolds, Henry Tedeschi
Membrane Potentials And Resistances Of Giant Mitochondria: Metabolic Dependence And The Effects Of Valinomycin, Bruce L. Maloff, Stylianos P. Scordilis, Christopher Reynolds, Henry Tedeschi
Biological Sciences: Faculty Publications
The membrane potentials and resistances of giant mitochondria from mice fed cuprizone have been studied. They were found to correspond approx. 10-20 mV, positive inside, and 2 M omega, respectively. These properties were found to be independent of the metabolic state. The microelectrodes were in the inner mitochondrial space since (a) the potentials in the presence of valinomycin depended on the K+ concentration of the medium and magnitude of the K+ diffusion potentials was consistent with the presence of a high internal concentration of K+, (b) almost identical results were obtained with mitochondria from which the external membrane had been …
The Kinetics Of Solvent Reorientation In Hydroxylated Solvents From The Exciting-Wavelength Dependence Of Chromophore Emission Spectra, John Milton, Robert M. Purkey, William C. Galley
The Kinetics Of Solvent Reorientation In Hydroxylated Solvents From The Exciting-Wavelength Dependence Of Chromophore Emission Spectra, John Milton, Robert M. Purkey, William C. Galley
WM Keck Science Faculty Papers
The disappearance of the exciting-wavelength dependence of the phosphorescence spectra of polar, aromatic chromophores in supercooled glycol–water mixtures is utilized to monitor the kinetics of solvent reorientation. Reorientation times in the nanosecond to second range are obtained for (3:2 v/v) glycerol–water and (1:1 v/v) ethylene glycol–water at 140–240 °K. The results suggest that the process is one involving a cluster of solvent molecules and in which the chromophore plays a relatively passive role. Steady-state data and direct measurements of phosphorescence shifts as a function of time indicate that the solvent reorientation process is nonexponential in nature. The decay function derived …
Alpine Vegetation Of Steens Mountain, Paul Collins
Alpine Vegetation Of Steens Mountain, Paul Collins
Dissertations and Theses
A determination was made that the summit of Steens Mountain is an alpine tundra. The assessment was based on floristics, vegetation and community structure, environmental parameters, and geomorphological criteria. Microhabitats of Oxyria digyna at low elevations were found to approximate alpine conditions.