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Littoral And Limnetic Zooplankton Communities In Lake Mead, Nevada-Arizona, Usa, Patrick J. Sollberger, Larry J. Paulson Jan 1991

Littoral And Limnetic Zooplankton Communities In Lake Mead, Nevada-Arizona, Usa, Patrick J. Sollberger, Larry J. Paulson

Publications (WR)

Zooplankton were collected from adjacent littoral and limnetic sites in Lake Mead, Nevada-Arizona, USA. Limnetic species dominated both littoral and limnetic zooplankton communities; littoral species rarely exceeded 2% of monthly total zooplankton densities. Low species richness of littoral taxa and high similarity in species composition between littoral and limnetic habitats appeared to result from uniform horizontal physical and chemical environments, due to horizontal mixing, and from the absence aquatic macrophytes. Significant differences in spatial distribution occurred in phytoplankton biomass, total zooplankton density, and fish "abundances; highest concentrations of these factors occurred nearest an inflow high in nutrients and progressively declined …


Magnetic Fine Particles In Biological Systems, Dominic P.E. Dickson, Richard B. Frankel Jan 1991

Magnetic Fine Particles In Biological Systems, Dominic P.E. Dickson, Richard B. Frankel

Physics

Two examples of biological magnetic fine particles are considered: iron-storage proteins and magnetotactic bacteria. These cover many aspects of this field, including the use of well-defined biological systems for testing theoretical models, using magnetic properties to distinguish between different biological materials, producing magnetic materials by biological processes, and using optimised biological magnetic systems as a guide to the production of synthetic magnetic materials.


New Bio-Analytical Separations Utilizing Chiral Mobile Phase Additives In Thin Layer Chromatography And Chiral Stationary Phases In High Performance Liquid Chromatography, Jo Dee Duncan Jan 1991

New Bio-Analytical Separations Utilizing Chiral Mobile Phase Additives In Thin Layer Chromatography And Chiral Stationary Phases In High Performance Liquid Chromatography, Jo Dee Duncan

Doctoral Dissertations

"The problem addressed by this dissertation is the separation of optical isomers in commercial as well as biological samples. The chromatographic separation of enantiomers is an important and rapidly developing field of study. Chiral separations of pharmaceutical compounds and important organic intermediates in high performance liquid chromatography (HPLC) and thin layer chromatography (TLC) were achieved. Two methods were employed for the direct liquid chromatographic resolution of chiral analytes: chiral stationary phases (CSPs) and chiral mobile phase additives (CMAs). Native and derivatized ß-cyclodextrins (ß-CD) were used as chiral stationary phases in reverse phase and normal phase HPLC, respectively. This study marked …


Development And Evaluation Of Tracer Particles For Use In Microzooplankton Herbivory Studies, Mary Putt Jan 1991

Development And Evaluation Of Tracer Particles For Use In Microzooplankton Herbivory Studies, Mary Putt

OES Faculty Publications

Two methods of preparing algae for use as tracer particles in single species measurements of microzooplankton herbivory were evaluated. Algae were either heat-killed and labelled with 5-(4,6-dichlorotriazin-2-yl amino fluorescein) (DTAF) (Rublee & Gallegos 1989; Mar, Ecol. Prog. Ser. 51: 221-227) or stained with hydroethidine (HYD). Both DTAF and HYD-stained algae were readily visible within the digestive vacuoles of most microzooplankton collected in estuarine and coastal waters of Massachusetts (USA) and preserved with Lugol's iodine. However, DTAF was ineffective at staining several chromophytic algae and the heat-kill process reduced cell volume by ≥ 50% in several of the algae which were …


Studies Related To Nutrients Entering Groundwater From The Heber Valley Sewer Farm And Dairies, Roland W. Jeppson, Joan Mclean, Calvin G. Clyde, Scott Korom Jan 1991

Studies Related To Nutrients Entering Groundwater From The Heber Valley Sewer Farm And Dairies, Roland W. Jeppson, Joan Mclean, Calvin G. Clyde, Scott Korom

Reports

Foreword: This report includes the results from a two year study in the Heber Valley to determine amounts of nutrients that are entering the groundwaters of the Heber Valley, and might ultimately enter Deer Creek Reservoir. Since Deer Creek Reservoir in Heber Valley, Utah supplies approximately 65 percent of the water distributed to Salt Lake County, the maintenance of its quality is of considerable importance. To maintain the quality of this reservoir and limit its eutrophication "best management" practices for surface water have been implemented gradually during the past decade in Heber Valley. These practices have significantly improved the qualities …


Functional Reasoning And Functional Modelling, J. Sticklen, William E. Bond Jan 1991

Functional Reasoning And Functional Modelling, J. Sticklen, William E. Bond

Computer Science Faculty Research & Creative Works

A car that will not start on a cold winter day and one that will not start on a hot summer day usually indicate two very different situations. When pressed to explain the difference, we would give a winter account- "Oil is more viscous in cold conditions, and that causes . . .'' -and a summer story- "Vapor lock is a possibility in hot weather and is usually caused by . . .'' How do we build such explanations? One possibility is that understanding how the car works as a device gives us a basis for generating the explanations. But …


Status Of Aluminum As A Risk Factor For Dialysis Encephalopathy And Alzheimer's Disease, P. B. Gorelick, D. (Daniel) B. Hier, C. Mangone, S. Robbins, A. Plioplys, S. Kathpalia Jan 1991

Status Of Aluminum As A Risk Factor For Dialysis Encephalopathy And Alzheimer's Disease, P. B. Gorelick, D. (Daniel) B. Hier, C. Mangone, S. Robbins, A. Plioplys, S. Kathpalia

Chemistry Faculty Research & Creative Works

No abstract provided.


Quantum Interference In Clothed-Ion-Atom Binary Peak Structures, C. O. Reinhold, D. R. Schultz, Ronald E. Olson, C. Kelbch, R. Koch, H. Schmidt-Böcking Jan 1991

Quantum Interference In Clothed-Ion-Atom Binary Peak Structures, C. O. Reinhold, D. R. Schultz, Ronald E. Olson, C. Kelbch, R. Koch, H. Schmidt-Böcking

Physics Faculty Research & Creative Works

An impulse approximation for ionizing collisions of clothed ions with atoms is used to explain the origin of an anomalous oscillation in the ejected electron spectrum in the region of the binary peak. In addition, measurements which evidence this feature for 1-MeV/u U21+ ions colliding with helium are presented. It is shown that this behavior arises from interference structures in the elastic differential cross section for the scattering of target electrons from the impinging ion and that it is associated with the well-known phenomenon of rainbow scattering. © 1991 The American Physical Society.


Estimation In A Marked Poisson Error Recapture Model Of Software Reliability, Rajan Gupta Jan 1991

Estimation In A Marked Poisson Error Recapture Model Of Software Reliability, Rajan Gupta

Mathematics & Statistics Theses & Dissertations

Nayak's (1988) model for the detection, removal, and recapture of the errors in a computer program is extended to a larger family of models in which the probabilities that the successive programs produce errors are described by the tail probabilities of discrete distribution on the positive integers. Confidence limits are derived for the probability that the final program produces errors. A comparison of the asymptotic variances of parameter estimates given by the error recapture and by the repetitive-run procedure of Nagel, Scholz, and Skrivan (1982) is made to determine which of these procedures efficiently uses the test time.


Stabilization/Solidification Of Organic Containing Wastes Using Organophilic Clay And Coal Fly Ash, Edith Lagoutte Dec 1990

Stabilization/Solidification Of Organic Containing Wastes Using Organophilic Clay And Coal Fly Ash, Edith Lagoutte

Theses

The relative merits of eight different coal fly ashes for use in the stabilization/Solidification of a waste containing both heavy metals and pentachlorophenol were investigated. Also studied, was the possible use of either untreated or treated (with hexade-cyl ammonium bromide) clay to enhance the stabilization of the organic. The sample composition was : 62% foundry baghouse dust (or 60% if 2% clay as added to the sample), 4.5% cement, 14% coal fly ash, 19.5% water. Pentachlorophenol was chosen as represen¬tative of the organic contamination. All tests were performed after curing the samples at 22°C, 98% Rh for 28 days. The …


Implementing Expert System Rule Conditions By Neural Networks, Henry Tirri Dec 1990

Implementing Expert System Rule Conditions By Neural Networks, Henry Tirri

Department of Computer Science Technical Reports

No abstract provided.


Resource Law Notes Newsletter, No. 21, Dec. 1990, University Of Colorado Boulder. Natural Resources Law Center Dec 1990

Resource Law Notes Newsletter, No. 21, Dec. 1990, University Of Colorado Boulder. Natural Resources Law Center

Resource Law Notes: The Newsletter of the Natural Resources Law Center (1984-2002)

No abstract provided.


Analyzing Images Containing Multiple Sparse Patterns With Neural Networks, Rangachari Anand, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka Dec 1990

Analyzing Images Containing Multiple Sparse Patterns With Neural Networks, Rangachari Anand, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka

Electrical Engineering and Computer Science - Technical Reports

We have addressed the problem of analyzing images containing multiple sparse overlapped patterns. This problem arises naturally when analyzing the composition of organic macromolecules using data gathered from their NMR spectra. Using a neural network approach, we have obtained excellent results in using NMR data to analyze the presence of amino acids in protein molecules. We have achieved high correct classification percentages (about 87%) for images containing as many as five substantially distorted overlapping patterns.


Radon Contamination Of Residences In A City Built Upon A Karst Landscape Bowling Green, Warren County, Kentucky, James William Webster Dec 1990

Radon Contamination Of Residences In A City Built Upon A Karst Landscape Bowling Green, Warren County, Kentucky, James William Webster

Masters Theses & Specialist Projects

The United States Environmental Protection Agency (EPA) estimates that 8 to 12% of U.S. homes have radon concentrations that equal or exceed 4 picocuries per liter (pCi/l). A statewide screening of Kentucky by EPA resulted in an average residential radon concentration of 2.8 pCi/l with 17% of the homes at or above 4 pCi/l. EPA requires routine monitoring and maintenance or worker health records in mines and caves having radon daughter concentrations at or above 0.30 working levels (WL).

Bowling Green is a city located in a karst region of south central Kentucky. Residents of Bowling Green have been subjected …


The Cytosolic-Binding Protein For The Immunosuppressant Fk-506 Is Both A Ubiquitous And Highly Conserved Peptidyl-Prolyl Cis-Trans Isomerase, John Siekierka, Gregory Wiederrecht, Heidi Greulich, D. Boulton, Shirley H.Y. Hung, John G. Cryan, P. J. Hodges, Nolan H. Sigal Dec 1990

The Cytosolic-Binding Protein For The Immunosuppressant Fk-506 Is Both A Ubiquitous And Highly Conserved Peptidyl-Prolyl Cis-Trans Isomerase, John Siekierka, Gregory Wiederrecht, Heidi Greulich, D. Boulton, Shirley H.Y. Hung, John G. Cryan, P. J. Hodges, Nolan H. Sigal

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

We have recently isolated an abundant cytosolic protein from human T-cells which specifically binds the immunosuppressive agent, FK-506. The FK-506-binding protein (FKBP) is a member of a novel class of proteins possessing peptidyl-prolyl cis-trans isomerase activity. These proteins are believed to play an important role in accelerating the rate at which proteins fold into their native conformations. In the present study, we demonstrate that FKBP is not a lymphoid-specific protein, but is widely distributed and phylogenically conserved. FKBP, purified from three sources (a human T-lymphocyte cell line JURKAT, bovine calf thymus, and Saccharomyces cerevisiae) exhibit identical molecular weights, immunological cross-reactivities, …


The Probe, Issue 106 - December 1990 Dec 1990

The Probe, Issue 106 - December 1990

The Probe: Newsletter of the National Animal Damage Control Association

THE PROBE
National Animal Damage Control Association
DECEMBER 1990
Message from the President
NADCA Membership Meeting in Lincoln
1990 NADCA Membership Directory


A Multi-Scale Approach For Recognizing Complex Annotations In Engineering Documents., Andrew Francis Laine, William Ball, Arun Kumar Dec 1990

A Multi-Scale Approach For Recognizing Complex Annotations In Engineering Documents., Andrew Francis Laine, William Ball, Arun Kumar

All Computer Science and Engineering Research

This paper describes a novel method of character recognition targeted for extracting complex annotations found in engineering documents. The results of this work will make it possible to capture the information contained in documents used to support facilities management and manufacturing. The recognition problem is made difficult in part because characters and text may be expressed in arbitrary fonts and orientations. Our approach includes a novel incremental strategy based on the multi-scale representation of wavelet decompositions. Our approach is motivated by biological mechanisms of the human visual systems. Using wavelets as a set of basis functions, we may decompose an …


A Report On Black-Tailed Prairie Dogs In Nebraska, Their Biology, Behavior, Ecology, Management, And Responses To A Visual Barrier Fence, Nancy S. Foster Dec 1990

A Report On Black-Tailed Prairie Dogs In Nebraska, Their Biology, Behavior, Ecology, Management, And Responses To A Visual Barrier Fence, Nancy S. Foster

School of Natural Resources: Dissertations, Theses, and Student Research

I examined the effects of a visual barrier fence, which had a see-through visibility of 600/0, on the foraging, vigilance, and aggressive behaviors of adult female black-tailed prairie dogs from June through August 1990 in central Nebraska. I also examined changes in their home ranges and use of an area in response to this fence. Prairie dogs prefer an open view of their surroundings. Therefore, I expected animals near a visual barrier to spend more time in vigilance and aggression, and less time foraging. Adult female prairie dogs exposed to the visual barrier devoted more time to foraging and less …


Optical Image Segmentation Using Wavelet Filtering Techniques, Christopher P. Veronin Dec 1990

Optical Image Segmentation Using Wavelet Filtering Techniques, Christopher P. Veronin

Theses and Dissertations

This research effort successfully implemented an automatic, optically based image segmentation scheme for locating potential targets in a cluttered FLIR image. Such a design is critical to achieve real-time segmentation and classification for machine vision applications. The segmentation scheme used in this research was based on texture discrimination and employs orientation specific, bandpass spatial filters as its main component. The orientation specific, bandpass spatial filters designed during this research include symmetrically located circular apertures implemented on heavy, black aluminum foil; cosine and sine Gabor filters implemented with detour-phase computer generated holography photoreduced onto glass slides; and symmetrically located circular apertures …


Determination Of The Optical Properties Of Organic Thin Films By Spectroscopic Ellipsometry, Mark L. Sward Dec 1990

Determination Of The Optical Properties Of Organic Thin Films By Spectroscopic Ellipsometry, Mark L. Sward

Theses and Dissertations

This thesis demonstrated the feasibility of determining the optical properties of organic and polymer thin films through the use of Spectroscopic Ellipsometry (SE). Tan Psi and cos Delta data from 300-800 nanometers (NM) were taken with a Rudolph Research s2000 spectroscopic ellipsometer four samples: indium tin oxide (ITO) coated glass; five layer poly-benzyl-L glutamate (PBLG) organic film on ITO coated glass; eight layer PBLG film on ITO coated glass; and a thiophene polymer film on a microscope slide. The data sets were fit to a choice of four computer models based on a paper written by Dwight Berreman in 1972. …


A Hydrogeological And Hydrogeochemical Investigation Of Groundwater At A Landfill For Sludge From The Kalamazoo Wastewater Treatment Plant, Richard Howard Christensen Dec 1990

A Hydrogeological And Hydrogeochemical Investigation Of Groundwater At A Landfill For Sludge From The Kalamazoo Wastewater Treatment Plant, Richard Howard Christensen

Masters Theses

Major cations and anions were analyzed to determine groundwater chemistry at a site used for the disposal of municipal sludge in the late 1960s and contaminated Portage Creek sedimem dredged in the late 1970s. The disposal site consists of five unlined basins constructed over 50 to 100 feet of stratified sand and gravel outwash underlain by silt and clay. Groundwater in the outwash is unconfined and flows from east to west. A groundwater divide in the center of the site produces local divergent flow to the northwest and southwest. Measurements of chemical constituents indicate that three factors influence groundwater chemistry …


Lake Mead Nutrient Enhancement Project, Peter D. Vaux, Larry J. Paulson, Nevada Department Of Wildlife, National Oceanic And Atmospheric Administration Dec 1990

Lake Mead Nutrient Enhancement Project, Peter D. Vaux, Larry J. Paulson, Nevada Department Of Wildlife, National Oceanic And Atmospheric Administration

Publications (WR)

The Lake Mead Fertilization Project is a research program designed to investigate the potential for using large-scale artificial fertilization to enhance the game fisheries of this reservoir through an increase in the population of threadfin shad, the system's primary forage species. A substantial decline in the population of largemouth bass, together with poor condition of adult striped bass, are the two major issues affecting the Lake Mead game fisheries. Both issues have been hypothesized to be a result of an inadequate amount of forage in the reservoir. Previous studies have in turn suggested that a major factor limiting the shad …


A Biologically-Inspired Neural Network Architecture For Image Processing, Laurence E. Lazofson Dec 1990

A Biologically-Inspired Neural Network Architecture For Image Processing, Laurence E. Lazofson

Theses and Dissertations

This thesis project included a literature survey of biological and artificial neural network research followed by development and testing of high- order and image recognition hierarchical neural network algorithms. Following training, performance testing of second-order and third-order networks yielded maximum accuracies comparable to those achieved by multilayer perceptron classifiers operating on test data sets. Several versions of an image classification algorithm were tested for learning performance using pixel data from forward-looking infrared (FLIR) images of tanks, trucks, target boards, and clutter. Employing the biologically-motivated Lambertization and contrast normalization of pixel windows, correlations with multiple Gabor function wavelets, and a 'phase …


Model-Based 3-D Recognition System Using Gabor Features And Neural Networks, Phung D. Le Dec 1990

Model-Based 3-D Recognition System Using Gabor Features And Neural Networks, Phung D. Le

Theses and Dissertations

A different approach to pattern recognition was attempted using Gabor features, artificial neural nets, and an image generator. The Gabor features and artificial neural nets are sound biological-based, and the image generator provides complete access to any view of an object. This thesis tested the idea that their integration could form a robust 3-D recognition system. The results of the research showed that the Gabor features together with a neural net were used successfully in classifying objects regardless of their positions, out-of- plane rotations, and to a lesser extent in-plane rotations. The Gabor features were obtained by correlating the image …


A Compact Optical Associative Memory Using Dynamic Holographic Storage Media And Photorefractive Gain And Attenuation Elements, Thomas J. Burns Dec 1990

A Compact Optical Associative Memory Using Dynamic Holographic Storage Media And Photorefractive Gain And Attenuation Elements, Thomas J. Burns

Theses and Dissertations

This research effort implemented a compact optical associative memory architecture consisting of a Fabry-Perot Confocal Resonator (FPCR) optical processing environment, two dynamically reprogrammable Lithium Niobate volume holograms, and Barium Titanate gain and attenuation elements. The reduced physical dimensions of the compact optical processing environment make it more adaptable to military applications than previous associative memory designs. The FPCR employs Mangin mirrors designed to reduce spherical aberrations in off-axis rays. The orientation of the gain element's grating vector angle and the model used to predict the profile of the attenuation element were unique to this research effort. The object stored in …


The Prairie Naturalist Volume 22, No. 4. December 1990 Dec 1990

The Prairie Naturalist Volume 22, No. 4. December 1990

The Prairie Naturalist

Paul B. Kannowski, Editor

Nikki R. Seabloom, Assistant Editor

Douglas H. Johnson, Book Review Editor

CONTENTS

DISTRIBUTION AND STATUS OF GREATER PRAIRIE-CHICKENS IN COLORADO ▪ B. F. Van Sant and C. E. Braun

IMPORTANCE OF AN OLD, MULTIPLE-USE RESERVOIR TO MIGRATING AND WINTERING DABBLING DUCKS ▪ D. M. Leslie, Jr. , and W. J. Stancill

SIMILARITY OF MALLARD NESTING ON A SOUTH DAKOTA ISLAND BETWEEN 1967-68 and 1985-87 ▪ S. G. Simpson and D. Limmer

BOBCAT HABITAT USE IN SOUTHEASTERN MONTANA DURING PERIODS OF HIGH AND LOW LAGOMORPH ABUNDANCE ▪ B. J. Giddings, G. L. Risdahl, and L. R. Irby …


State Of The Fisheries Report 1990, Fisheries Department Of Western Australia Dec 1990

State Of The Fisheries Report 1990, Fisheries Department Of Western Australia

Status Reports of the Fisheries and Aquatic Resources

The State of the Fisheries is published annually by the Fisheries Department as part of the statutory reporting process required under the Fisheries Act. This report covers developments and production in the State's fisheries up to the end of December 1990. Full details of the department's operations for this period are published separately in the department's annual reports for the financial years ending June 1990 and 1991. Figures provided in the tables are derived from catch returns completed by fishermen which are processed by the Australian Bureau of Statistics up to June 1990. Other information provided in the text comes …


Purification And Characterization Of A Dna Polymerase From The Cyanobacterium Anacystis Nidulans R2, Hsiu-Jin Lin, Gordon C. Cannon, Sabine Heinhorst Nov 1990

Purification And Characterization Of A Dna Polymerase From The Cyanobacterium Anacystis Nidulans R2, Hsiu-Jin Lin, Gordon C. Cannon, Sabine Heinhorst

Faculty Publications

A DNA polymerase has been highly purified from Anacystis nidulans R2. Electrophoretic analysis in sodium dodecyl sulfate-polyacrylamide gels revealed that the final fraction contains three bands of Mr 107,000, 93,000, and 51,000, respectively. Analysis of purified DNA polymerase activity in situ indicates that of the three polypeptides the Mr 107,000 species has the catalytic activities. The native molecular weight of the enzyme was estimated by glycerol gradient sedimentation to be 100,000. The enzyme has an absolute requirement for a divalent cation. Mg2+ can be replaced with Mn2+, but the DNA polymerase is less active. Potassium …


Coupled Kinetic Analysis Of Cleavage Of Dna By Esperamicin And Calicheamicin, Hiroko Kishlkawa, Ying-Ping Jiang, Jerry Goodisman Nov 1990

Coupled Kinetic Analysis Of Cleavage Of Dna By Esperamicin And Calicheamicin, Hiroko Kishlkawa, Ying-Ping Jiang, Jerry Goodisman

Chemistry - All Scholarship

A coupled kinetic analysis of esperamicin, calicheamicin, and DNase I cleavage of covalently closed circular PM2 DNA has been carried out. Analysis of the optical density data derived from agarose gel electrophoresis experiments shows that esperamicin A,, like the hydrolytic enzyme DNase I, produces mainly single-strand breaks in DNA. These agents cause covalently closed circular form I DNA to be initially converted to nicked circular form I1 DNA. However, the ratio of the rate constant for this process (k,') to that associated with conversion of form I1 to linear form I11 DNA ( k i ) is not consistent with …


Part I: Oxidation Of Heavy Metal Sulfides In Relation To The Environment; Part Ii: Fundamental Theory & Experiments Concerning Gas Chromatography & Mass Spectrometry, Judith Morgan Nov 1990

Part I: Oxidation Of Heavy Metal Sulfides In Relation To The Environment; Part Ii: Fundamental Theory & Experiments Concerning Gas Chromatography & Mass Spectrometry, Judith Morgan

Masters Theses & Specialist Projects

Oxidation of heavy metal sulfides is a thermodynamically spontaneous process. Because of this, metal sulfides in the presence of oxygen are not stable. Currently there are over 100 streams and rivers, within the U.S., contaminated with heavy metal mine drainage; therefore an approved method of restoration is necessary. Precipitation of heavy metals as sulfides using H2S as a reductant has been favorably reviewed as a restorative technique to clean up mining areas. However, using this technique on the laboratory scale does not prove to be a viable answer and shows strong pH dependence.

In the past three years …