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The Influence Of Redd Distribution And Microhabitat Availability On The Distribution And Abundance Of Young-Of-The-Year Trout In The Green River, Utah, Michael J. Buntjer May 1992

The Influence Of Redd Distribution And Microhabitat Availability On The Distribution And Abundance Of Young-Of-The-Year Trout In The Green River, Utah, Michael J. Buntjer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Redd distribution, redd density, and physical habitat were used to explain the distribution and abundance of young-of-the-year (YOY) brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss) in the Green River, Utah. The importance of variables at both a microhabitat and macrohabitat scale were assessed using stepwise regression analysis. Availability of cover (rock and vegetation) and proximity to spawning sites were the most important variables used to explain the distribution and abundance of YOY brown trout and rainbow trout. In addition, YOY brown trout and rainbow trout occupied specific microhabitats and showed patterns of use for …


An Embedded Ring Approach To The Vibrational Dynamics Of Disordered Two-Dimensional Materials, Timothy Edwin Doyle May 1992

An Embedded Ring Approach To The Vibrational Dynamics Of Disordered Two-Dimensional Materials, Timothy Edwin Doyle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A theoretical approach was developed to model the vibrational dynamics of amorphous, two-dimensional materials. The materials were modeled as continuous random networks (CRN's) comprising an assemblage of planar rings of diverse size. In-plane vibrational modes for symmetric 4-, 5-, 6-, 7-, and 8-membered rings were examined. Vibrational states of isolated rings were modified by coupling the rings to a continuous network to represent rings embedded in a CRN. An effective force constant was used to couple the ring vibrations to the network's collective motions. Potentials were approximated with the use of a central force model (bond-stretching force constant) and a …


Effects Of Polyacrylamide On Rangeland Soils And Plants, Saud Leily R. Al-Rowaily May 1992

Effects Of Polyacrylamide On Rangeland Soils And Plants, Saud Leily R. Al-Rowaily

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objectives of this study were to determine the effects of two forms of polyacrylamide (PAM) conditioners (Cross-linked and Non-cross-linked PAM) on evaporation, saturated hydraulic conductivity, water retention, crust and crack formation of soils, seed germination, and seedling and tubeling growth.

The two PAM conditioners, 0.2% concentration by weight, were mixed with seven soils of different textures (sandy loam, silt, silty clay loam, silt loam, fine sand, medium sand, and coarse sand) to investigate the effects on evaporation, saturated hydraulic conductivity, and water retention. Soil samples of different textures were brought to field capacity and placed in a growth chamber …


Sedimentology And Community Structure Of Reefs Of The Yucatan Peninsula, Mexico, Matthew J. Novak May 1992

Sedimentology And Community Structure Of Reefs Of The Yucatan Peninsula, Mexico, Matthew J. Novak

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Holocene carbonate sediments from Mexican reefs in the Caribbean and Gulf of Mexico display variations in constituent composition, texture and mineralogy which are related to their locations on the reefs. Samples were collected at barrier reef environments at Akumal and Chemuyil, on the northeast coast of the Yucatan Peninsula; at the oceanic atoll of Chinchorro, off the southeast coast of the peninsula; and at the shelf atoll of Alacranes, in the Gulf of Mexico. Samples were collected through a depth range of 0-40 m, which encompasses back reef, shallow fore reef, and deeper fore reef environments.

Constituent-particle analysis of reef …


Dynamic Multi-Species Animal Habitat Modeling With Forest Succession Models, Stephen A. Compton May 1992

Dynamic Multi-Species Animal Habitat Modeling With Forest Succession Models, Stephen A. Compton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research determines and demonstrates the ability to simulate dynamic multi-species animal habitat suitability with forest succession models. A literature review of dynamic animal habitat models is presented. The structure of an existing forest simulation model (MASS10) was modified from a basal area-based model to a volume-based model (DYNAM10). The forest model was calibrated using data from permanent-plot growth and vegetation samples collected by USDA Forest Service Forest Survey procedures. The theoretical growth parameters used to simulate stand development were validated. Predictions of DBH and height growth, as well as stand-level behavior, were verified. A subroutine, VEGDYN, was added to …


Soil Heterogeneity And Its Exploitation By Plants, Robert B. Jackson May 1992

Soil Heterogeneity And Its Exploitation By Plants, Robert B. Jackson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In this dissertation I first examine the ability of individual plants in the field to garner localized soil nutrients. I then measure actual soil variability around perennial plants and use various statistics to quantify the scale and degree of that variability.

Soil patches on opposite sides of Pseudoroegneria spicata tussocks were treated with distilled water or a nutrient solution containing N, P, or K in three field experiments. When P was augmented in the enriched soil patches, rates of P uptake increased significantly for roots from enriched patches compared with roots in control patches. Rates of ammonium and potassium uptake …


Disconjugacy And Oscillation Theory Of Linear Differential And Difference Equations, Yuhua Xu May 1992

Disconjugacy And Oscillation Theory Of Linear Differential And Difference Equations, Yuhua Xu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation is both a literature survey and a presentation of new and independent results.

The survey gives an overview of disconjugacy and oscillation theory for linear differential and difference equations with an emphasis on comparing the theory of difference equations to the theory of differential equations. Second order scalar equations, higher order scalar equations, matrix equations (systems) and Hamiltonian systems are discussed. A chapter on three-term recurrences of systems is also included. Both similarities and differences between differential and difference equations are described.

The new and independent results are for Hamiltonian systems of difference equations. Those results include the …


Hopf Bifurcation In A Parabolic Free Boundary Problem, Yoon-Mee Lee May 1992

Hopf Bifurcation In A Parabolic Free Boundary Problem, Yoon-Mee Lee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We deal with a free boundary problem for a nonlinear parabolic equation, which includes a parameter in the free boundary condition. This type of system has been used in models of ecological systems, in chemical reactor theory and other kinds of propagation phenomena involving reactions and diffusion.

The main purpose of this dissertation is to show the global existence, uniqueness of solutions and that a Hopf bifurcation occurs at a critical value of the parameter r. The existence and uniqueness of the solution for this problem are shown by finding an equivalent regular free boundary problem to which existence …


Mobilization Of Iron Enhances The Iron-Dependent Biochemical Reactivity Of Asbestos In Vitro And Contributes To The Cytotoxicity Of Asbestos In Cultured Cells, Loren Glen Lund May 1992

Mobilization Of Iron Enhances The Iron-Dependent Biochemical Reactivity Of Asbestos In Vitro And Contributes To The Cytotoxicity Of Asbestos In Cultured Cells, Loren Glen Lund

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Asbestos related research began approximately 60 years ago, yet, the mechanism(s) by which asbestos exerts its biological effects is not well understood. The hypothesis upon which this dissertation is based is that mobilization of iron from asbestos enhances the iron-dependent biochemical reactivity of asbestos in vitro and contributes to asbestos-dependent cytotoxicity. The specific aims for this hypothesis were, 1) to determine whether iron was responsible for the biochemical reactivity of asbestos in vitro and asbestos-induced cytotoxicity in cultured cells, and 2) to determine whether mobilization of iron from asbestos enhanced the reactions catalyzed by asbestos in vitro and contributes to …


104th Session Iowa Academy Of Science Awards Luncheon, April 24, 1992, Iowa Academy Of Science Apr 1992

104th Session Iowa Academy Of Science Awards Luncheon, April 24, 1992, Iowa Academy Of Science

Iowa Academy of Science Documents

Program:

--- Introduction of Head Table - Luther Erickson, President, Iowa Academy of Science
--- Recognition of students participating in various statewide activities; STARS Awards - Larry Schwinger, Chair, Student Programs Committee
--- Presentation of scholarship winners and 1993 AJAS representatives - Peggy Tilgner, Wartburg College, Waverly
--- Presentation of Excellence in Science Teaching Awards - Roy Unruh, Director, ESTA Program


The Annual Meeting Of The Iowa Academy Of Science April 24-25, 1992 [Program, 104th Meeting], Iowa Academy Of Science Apr 1992

The Annual Meeting Of The Iowa Academy Of Science April 24-25, 1992 [Program, 104th Meeting], Iowa Academy Of Science

Iowa Academy of Science Documents

Contents:

Program Summary --- 5
General Session Speakers --- 9
Awards --- 12
Distinguished Fellow --- 12
Distinguished Service --- 13
Symposia Programs --- 14
Poster Session --- 16
Campus Map --- Centerfold
Section Programs --- 18
Agricultural Sciences --- 18
Anthropology --- 20
Botany --- 21
Cellular & Molecular Biology --- 22
Chemical Education --- 26
Chemistry, Inorganic --- 26
Chemistry, Organic --- 27
Conservation --- 29
Earth Science Teaching --- 30
Elementary Science Teaching --- 30
Engineering --- 32
Geology --- 34
Linguistics --- 35
Nursing --- 36
Physics --- 37
Physiology --- 39
Psychology --- 40
Science …


Program Abstracts, 104th Session, Iowa Academy Of Science, April 24-25, 1992, Iowa Academy Of Science Apr 1992

Program Abstracts, 104th Session, Iowa Academy Of Science, April 24-25, 1992, Iowa Academy Of Science

Iowa Academy of Science Documents

Presentation abstracts from the annual meeting of the Iowa Academy of Science


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 8, Number 4, April 1992, College Of Engineering And Computer Science, Wright State University Apr 1992

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 8, Number 4, April 1992, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.


The Gamut: A Journal Of Ideas And Information, No. 35, Spring 1992, Cleveland State University Apr 1992

The Gamut: A Journal Of Ideas And Information, No. 35, Spring 1992, Cleveland State University

The Gamut Archives

CONTENTS OF ISSUE NO. 35, SPRING, 1992

Editorial

Louis T. Milic: IT’s the Thought That Counts, 3

Civil Rights

Jonathan L. Entin: Going Around and Coming Around in Prince Edward County, 5

An ironic twist in the long road to desegregation

Animal Rights

Pamela Harrison: Saving Dolphins, Not Eating Meat, 15

A moral basis for vegetarianism

Robert J. White: The Animal Rights Movement: A New Pseudo-Religion

Activists sabotage medical research

Ted Bartlett: Animals are Not People

Whose best interest is involved?

China

Peter Scheckner: American Movies in China, 30

E.T. and Crocodile Dundee in Tiananmen …


Poems Taken From "An Evening Of Mathematical Poetry" Apr 1992

Poems Taken From "An Evening Of Mathematical Poetry"

Humanistic Mathematics Network Journal

No abstract provided.


Santa Clara Magazine, Volume 34 Number 3, Spring 1992, Santa Clara University Apr 1992

Santa Clara Magazine, Volume 34 Number 3, Spring 1992, Santa Clara University

Santa Clara Magazine

12 - EAST L.A. STORY Jesuit-run Dolores Mission Alternative School is a last chance for East L.A.'s troubled teen-agers, many of whom are members of violent Latino gangs. By Rene Romo '86

20 - ONE IS TOO MANY TWO ARE NOT ENOUGH A personal account of one woman's struggle with alcohol addiction. By Lisa Agrimonti '87

24 - UP CLOSE: WITOLD KRASSOWSKI After five years in the Polish Underground Army during WW II, the founder of SCU's Sociology Department came to America and discovered teaching. His 40-year commitment to students has never waivered. By Christine Spielberger '69

28 - WORKING …


Electron Production In Proton Collisions With Atoms And Molecules: Energy Distributions, M. Eugene Rudd, Y.-K. Kim, D. H. Madison, Timothy J. Gay Apr 1992

Electron Production In Proton Collisions With Atoms And Molecules: Energy Distributions, M. Eugene Rudd, Y.-K. Kim, D. H. Madison, Timothy J. Gay

Timothy J. Gay Publications

All known data on the energy distribution of secondary electrons from collisions of protons with atoms and molecules have been reviewed and differential cross sections have been collected. The two experimental methods used to obtain the data are discussed and possible sources of error pointed out. Theoretical treatments are reviewed and several methods of checking the consistency of the data are discussed. Two semiempirical models have been chosen to represent the differential cross sections, and parameters for these models are given which fit the average of the experimental data, subject to known constraints. Recommended values of differential cross sections are …


The Probe, Issue 120 - April 1992 Apr 1992

The Probe, Issue 120 - April 1992

The Probe: Newsletter of the National Animal Damage Control Association

THE PROBE
National Animal Damage Control Association
APRIL 1992
Laughing Gulls-Aircraft Collisions Increasing Hazard at JFK
Calendar of Upcoming Events
Animal Damage Control in the News:
WLFA Alerts Hunters to Proposed Arizona Law
Spring Bear Hunt Phased Down in Colorado
Black Vultures a “Hot” Item in Louisiana
Fur Industry on a Comeback?
Texas State Representative Strongly Supports ADC Efforts
Critical Issues Facing the ADC Program
Jim Forbes Wins Membership Incentive Content
Maury Bedford Designs Winning Logo
Species Solidarity Urged by Reader's Digest Writer
NADCA Business Meeting Held March 4 in Newport Beach
10th Great Plains Wildlife Damage Control Workshop Available …


Epistemological Pluralism: Styles And Voices Within The Computer Culture, Sherry Turkle, Seymour Papert Apr 1992

Epistemological Pluralism: Styles And Voices Within The Computer Culture, Sherry Turkle, Seymour Papert

Humanistic Mathematics Network Journal

No abstract provided.


What Is Mathematics And Why Don't They Know That?, Harald M. Ness Apr 1992

What Is Mathematics And Why Don't They Know That?, Harald M. Ness

Humanistic Mathematics Network Journal

No abstract provided.


Mathematics From An English Major's Point Of View, Elizabeth Miller, Kathleen M. Shannon Apr 1992

Mathematics From An English Major's Point Of View, Elizabeth Miller, Kathleen M. Shannon

Humanistic Mathematics Network Journal

No abstract provided.


Thermal Properties Of Some Lipid Components Of Cell Membranes, Lihua Wei Apr 1992

Thermal Properties Of Some Lipid Components Of Cell Membranes, Lihua Wei

Masters Theses & Specialist Projects

Phospholipids are the major structural components of the lipid portion of biological membranes. The study of the thermal properties of these phospholipid provides a systematic understanding of the relationships between the chemical structures and functional properties of phospholipid molecules in artificial and biological membranes. This study examined the thermal behavior of phospholipids in the solid state using DSC and TG coupled with FITR. The phospholipids were found to have phase transitions below the melting point. Egg-yolk lecithin had four transitions below its melting point; sphingomyelin had two phase transitions below its melting point. Phosphatidylethanolamine and phosphatidylserine had complex phase transitions. …


Electron Production In Proton Collisions With Atoms And Molecules: Energy Distributions, M. Eugene Rudd, Yongki Kim, Don H. Madison, Timothy Gay Apr 1992

Electron Production In Proton Collisions With Atoms And Molecules: Energy Distributions, M. Eugene Rudd, Yongki Kim, Don H. Madison, Timothy Gay

Physics Faculty Research & Creative Works

All known data on the energy distribution of secondary electrons from collisions of protons with atoms and molecules have been reviewed and differential cross sections have been collected. The two experimental methods used to obtain the data are discussed and possible sources of error pointed out. Theoretical treatments are reviewed and several methods of checking the consistency of the data are discussed. Two semiempirical models have been chosen to represent the differential cross sections, and parameters for these models are given which fit the average of the experimental data, subject to known constraints. Recommended values of differential cross sections are …


Water Current, Volume 24, April 1992 Apr 1992

Water Current, Volume 24, April 1992

Water Current Newsletter

Kusler Opens, Closes Water Conference: Sets Tone for "Living with Wetland Policies, Politics'
Governor's Speech Calls for Balance for Wetlands Policy
Water Celebrated
USGS Funds Awarded
Report from the Director: Consortium Formed to Promoted Informed Decision-Making
Progress Award Goes to Nebraska Groundwater Foundation
Heimlich Presents National Economic Perspective on Wetlands
Pioneer Irrigation Award to Hastings Irrigation Pipe Company
Proceedings Available of 1990 NATO Advanced Research Workshop on Nitrate Contamination


The Application Of A Statistical Trend Analysis Program To Ground-Water Quality Monitoring Data From Eight Western Michigan Solid Waste Landfills, Amy Decosta Lachance Apr 1992

The Application Of A Statistical Trend Analysis Program To Ground-Water Quality Monitoring Data From Eight Western Michigan Solid Waste Landfills, Amy Decosta Lachance

Masters Theses

A statistical analysis and interpretation of ground-water chemistry data from eight landfills in Western Michigan was performed. Data were collected over approximately the past ten years, pursuant to the requirements of Michigan's Solid Waste Management Act. A statistical regression model was used to reduce the data to identifiable trends and estimated magnitudes. These results were analyzed with respect to each landfill's characteristics and hydrogeological setting. Comparisons were made concerning the landfills' relative potential for environmental harm. Also, the effectiveness and applicability of this model to the analysis of ground-water monitoring data was assessed.

It was concluded that this analysis and …


Feature Extraction And Classification Of Flir Imagery Using Relative Locations Of Non-Homogeneous Regions With Feedforward Neural Networks, Kevin L. Priddy Apr 1992

Feature Extraction And Classification Of Flir Imagery Using Relative Locations Of Non-Homogeneous Regions With Feedforward Neural Networks, Kevin L. Priddy

Theses and Dissertations

The classification of forward looking infrared (FLIR) imagery is explored using Gabor transform decomposition and relative locations of non- homogeneous regions combined with feedforward neural networks. A feature saliency metric is developed from a Bayesian sensitivity analysis of feedforward neural networks. This metric is then used to reduce the dimensionality of the feature vectors used to identify FLIR imagery without any degradation of classification accuracy. Several system architectures are developed using a roving window combined with a series of Gabor filters to produce feature vectors for presentation to a neural network classifier. One architecture uses the Gabor filter coefficients to …


Angular Distributions For Near-Threshold (E,2E) Processes For H, He, And Other Rare-Gas Targets, Cheng Pan, Anthony F. Starace Apr 1992

Angular Distributions For Near-Threshold (E,2E) Processes For H, He, And Other Rare-Gas Targets, Cheng Pan, Anthony F. Starace

Anthony F. Starace Publications

Distorted-wave calculations of the triply differential cross sections for electron-impact ionization of H, He, Ne, Ar, Kr, and Xe are presented for final-state electrons sharing ≤4 eV excess energy and for the coplanar, θ12=π geometry. Results for H and He targets, presented briefly elsewhere [C. Pan and A. F. Starace, Phys. Rev. Lett. 67, 185 (1991)], are analyzed in greater detail and compared with available experimental and other theoretical results. In particular, for He targets the effects of exchange and of second-order capture processes are exhibited. These are shown to be of lesser importance than other short-range effects …


Factors Affecting The Kinetics Of Light Intensity Adaptation In Marine Phytoplankton, Chunzhi Guo Apr 1992

Factors Affecting The Kinetics Of Light Intensity Adaptation In Marine Phytoplankton, Chunzhi Guo

OES Theses and Dissertations

It has been suggested that the recent light history of phytoplankton and the kinetics of photoadaptation can be used to provide information about the vertical mixing processes in the upper mixed layer. To be useful as a parameter in a model of photoadaptation and vertical mixing, the response of a photoadaptive variable to changes in growth irradiance must be monotonic, significant, and comparable in time rate scale to mixing processes. Previous studies of photoadaptation kinetics have focused on the response of phytoplankton to changes in light intensity under continuous illumination. This dissertation attempts to elucidate the effects of light:dark cycle, …


The Growth And Bioenergetics Of Callinectes Sapidus Larvae And The Effects Of Diet Quality On Larval Physiology, James J. Pletl Apr 1992

The Growth And Bioenergetics Of Callinectes Sapidus Larvae And The Effects Of Diet Quality On Larval Physiology, James J. Pletl

OES Theses and Dissertations

Food quality, especially ω3 polyunsaturated fatty acids (PUFA), can affect the physiology and metabolic efficiency of larvae of the blue crab, Callinectes sapidus. These affects may correlate with success in development and juvenile recruitment.

Larvae were exposed to two diets differing quantitatively in ω3 PUFA and respiration, excretion, growth, and feeding rates were measured for each larval stage and the megalopal stage. The energy partitioned to molts and specific dynamic action was also measured. T

he ω3 PUFA enriched diet resulted in a lower respiration rate when compared to the unsupplemented diet, but there was little differences in excretion …


Biodegradation Of Crude Oil By Marine Higher Fungi, Brian J. Dyer Apr 1992

Biodegradation Of Crude Oil By Marine Higher Fungi, Brian J. Dyer

Biological Sciences Theses & Dissertations

Four experiments were performed to determine the ability of marine higher fungi to grow in and degrade crude oil. Eight species, previously determined to be hydrocarbonoclastic, were grown in artificial sea water medium (ASM) and southern Louisiana crude oil. The dry mycelial weights were measured and consumption of crude oil was measured gravimetrically. The two species with the best growth, Corollospora maritima and Zalerion maritimum, were grown in ASM containing crude oil spiked with three known hydrocarbons. To this was added glucose (0.15%) and incubated 49 days to test for possible cometabolism of hydrocarbons. Hydrocarbons remaining in the growth …