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Seasonal And Diel Patterns Of Abundance And Productivity Of Phototrophic Picoplankton In The Lower Chesapeake Bay, Lewis Francis Affronti Jr. Jul 1990

Seasonal And Diel Patterns Of Abundance And Productivity Of Phototrophic Picoplankton In The Lower Chesapeake Bay, Lewis Francis Affronti Jr.

Biological Sciences Theses & Dissertations

This study was performed to evaluate phototrophic pico-plankton (0.2 to 2.0 μm) dynamics within the lower Chesapeake Bay. A 15 month study of phototrophic picoplankton abundance and productivity was made from June 1988 to October 1989. Annual picoplankton abundance using epifluorescence microscopy ranged from 7.26 x 106 cells/1 in the winter to 9.28 x 108 cells/1 during late summer.

In situ incubations of natural picoplankton populations over the 15 month study were used to test the applicability of the frequency of dividing cells technique in estimating phototrophic picoplankton growth rates. The regression equation o fμ = 2.37 x …


Kerr Effect Of Two-Medium Layered Systems, Liang-Yao Chen, William A. Mcgahan, Z.S. Shan, David J. Sellmyer, John A. Woollam Jun 1990

Kerr Effect Of Two-Medium Layered Systems, Liang-Yao Chen, William A. Mcgahan, Z.S. Shan, David J. Sellmyer, John A. Woollam

David Sellmyer Publications

Detailed and practical expressions are given for the magneto-optical Kerr effect (MOKE) for various configurations of two media. One is a magneto-optic (MO) one, and the other is a nonmagnetic (NM) medium. For a system of two thick media with a single interface, with a first-order approximation in MOKE term Q, the Kerr function is determined by the product of a MOKE term Q and an optical term η. A second type of system includes a thin MO (or NM) layer deposited on a thick NM (or MO) substrate. For a MO/(NM-substrate) configuration, the Kerr function is related to …


Shifting Water To Urban Uses: Activities Of The Metropolitan Water District Of Southern California, Timothy H. Quinn Jun 1990

Shifting Water To Urban Uses: Activities Of The Metropolitan Water District Of Southern California, Timothy H. Quinn

Moving the West's Water to New Uses: Winners and Losers (Summer Conference, June 6-8)

36 pages.

Contains references.


Water Transfers: Can They Protect And Enhance Rural Economies?, Michael J. Clinton Jun 1990

Water Transfers: Can They Protect And Enhance Rural Economies?, Michael J. Clinton

Moving the West's Water to New Uses: Winners and Losers (Summer Conference, June 6-8)

16 pages.


Computer Viruses--A Form Of Artificial Life?, Eugene H. Spafford Jun 1990

Computer Viruses--A Form Of Artificial Life?, Eugene H. Spafford

Department of Computer Science Technical Reports

No abstract provided.


Using Management Techniques To Solve Environmental Problems, Patrick D. Kelly Jun 1990

Using Management Techniques To Solve Environmental Problems, Patrick D. Kelly

RISK: Health, Safety & Environment (1990-2002)

Arguing that little effective progress is being made in solving problems of varying urgency, this paper suggests a leadership role for science and engineering societies. It proposes that such societies attempt to prioritize problems and attempt to focus public awareness (and calls to action) in a more systematic way.


Thermal Desorption Of Contaminated Soils, Chengdi Dong May 1990

Thermal Desorption Of Contaminated Soils, Chengdi Dong

Theses

The objectives of this research are of twofold, namely, to investigate the desorption behaviors of hazardous constituents evolved from several types of contaminated soils, and to evaluate the in-situ thermal treatment of organic chemical contaminated soil.

Two clay soil minerals and a silty sand with five organic compounds, dichlorophenol, trichlorophenol, pentachlorophenol, trichloroethylene, and tetrachloroethylene (TCE) were used in this study. The desorption behaviors were evaluated by thermogravimetric analyzer (TGA) and a simulator of in situ desorption by heating probes. The results of TGA analysis revealed that a completely removal of organic contaminants can be achieved in a moderate temperature. They …


X-Ray Powder Diffraction, Scanning Electron Microscopy And Energy Dispersive Spectroscopy Studies Of Soil Containing Chromium Immobilized By Microwave Treatment, Nagui Ibrahim May 1990

X-Ray Powder Diffraction, Scanning Electron Microscopy And Energy Dispersive Spectroscopy Studies Of Soil Containing Chromium Immobilized By Microwave Treatment, Nagui Ibrahim

Theses

The orientation of soil contaminants such as chromium is altered during microwave heating. The SEM and EDS were utilized in the study. The nature of the orientation is related to the heating time. This results in immobilizing the contaminant in leaching tests. The non-leachibility was related to the reactivity of the chromium salt with the soil hematite phase (Fe2O3) during the microwaving. This was proved By the X-ray diffraction analysis. The spectrums obtained from 30 and 60 minutes microwaved samples were identical in the crystal phases and were significantly different from the contaminated unheated sample.


A Comparative Study Of Cadmium Uptake By Cells Of Gram-Positive And Gram-Negative Bacteria, Shubhangi Rajan Bhende May 1990

A Comparative Study Of Cadmium Uptake By Cells Of Gram-Positive And Gram-Negative Bacteria, Shubhangi Rajan Bhende

Theses

Cadmium uptake by cells of Gram-positive and Gram- negative bacteria was studied. Gram-positive and Gram- negative bacterial cells were separated from activated sludge collected from the Parsippany Troy Hills Water Pollution Control Plant (NJ) by isolating them on agar plates. These were grown separately and used for uptake experiments.

Gram-positive bacterial cells showed 17% more uptake of cadmium as compared to Gram-negative cells at 30°C and pH 6.6. More than 95% of the total cadmium removal from the solution was observed during first 5 min. of cell-metal contact time. In case of Gram-positive bacteria cadmium uptake decreased by 5-10% after …


Visual Protocol Collection For The Enhancement Of The Radiological Diagnostic Process, Erika Rogers, Ronald C. Arkin, M. Baron, N. Ezquerra, E. Garcia May 1990

Visual Protocol Collection For The Enhancement Of The Radiological Diagnostic Process, Erika Rogers, Ronald C. Arkin, M. Baron, N. Ezquerra, E. Garcia

Computer Science and Software Engineering

This paper describes the Observation Phase of a research project that is designed to explore the nature of visual radiological diagnosis. It is concerned with the collection and analysis of visual protocol data in an effort to determine the salient image features that may impact on the different stages of the diagnostic process, both perceptual and cognitive. These features, once identified, will lead to the formulation of image enhancement hypotheses and the development of knowledge-based visualization techniques to assist the radiological diagnostic process.


Two-Dimensional Gel Electrophoretic Analysis Of Cellular Proteins From Escherichia Coli In The Presence Of Mutated And Homologous Genes For 4.5s Rna, Michael O'Loughlin May 1990

Two-Dimensional Gel Electrophoretic Analysis Of Cellular Proteins From Escherichia Coli In The Presence Of Mutated And Homologous Genes For 4.5s Rna, Michael O'Loughlin

Senior Scholar Papers

4.5S RNA is a small. stable, required molecule in Escherichia coli whose precise function is not known. Previous evidence suggests an involvement with the ribosome during translation. In this study, four base insertion and four base deletion mutations were constructed in a plasmid borne copy of the 4.55 RN A gene. These copies and two homologous genes from Pseudomonas aeruginosa and Thermus thermophilus were transformed into an E. coli strain which then had its only wild-type 4.5S RNA gene inactivated. In order to assess the effect of the alternative gene copies. the patterns of proteins synthesized in the presence of …


An Analytic Representation Of The Radial Distribution Of Dose From Energetic Heavy Ions In Water, Si, Lif, Nai, And Sio2, Robert Katz, Kim Sum Loh, Luo Baling, Guo-Rong Huang May 1990

An Analytic Representation Of The Radial Distribution Of Dose From Energetic Heavy Ions In Water, Si, Lif, Nai, And Sio2, Robert Katz, Kim Sum Loh, Luo Baling, Guo-Rong Huang

Robert Katz Publications

An earlier representation of the radial distribution of dose about the path of a heavy ion in liquid water is modified and extended to include silicon, lithium fluoride, sodium iodide, and silicon dioxide.


Determination Of The Suitability Of Arkansas River Water For Municipal, Industrial And Agricultural Use: Volume 3 Treatability Study, Steven M. Jones, Steven G. Burghart, James W. Moore May 1990

Determination Of The Suitability Of Arkansas River Water For Municipal, Industrial And Agricultural Use: Volume 3 Treatability Study, Steven M. Jones, Steven G. Burghart, James W. Moore

Arkansas Water Resources Center Technical Reports

Volume III of the overall report for the project to determine the suitability of the Arkansas River for municipal, agricultural and industrial water supplies contains the treatability data. These data include the results of the granular activated carbon, ozonation and packed tower aeration studies. The research project was conducted under contract with the Arkansas Soil and Water Conservation Commission. Funding was provided by the Corps of Engineers, the Environmental Protection Agency, the City of Little Rock, Rockefeller Foundation and the Ozark Society. Additionally, the U.S. Geological Survey contributed financially by matching the cost of sample collection. The City of Little …


Pair-Correlation Kinetics And The Reversible Diffusion-Controlled Reaction, David Peak, D C. Greenlaw, L A. Schick May 1990

Pair-Correlation Kinetics And The Reversible Diffusion-Controlled Reaction, David Peak, D C. Greenlaw, L A. Schick

All Physics Faculty Publications

It has long been known that the time course of a bimolecular reaction occurring in a condensed host depends on the behavior of the nonequilibrium pair-correlation function for reactant pairs. The classical analysis of such reactions has led to a kind of standard rule: The association rate constant for a diffusion-controlled reaction is 4πDR and this rate constant produces the fastest possible kinetics. This result is only (approximately) true for the case of an irreversible reaction, however. Here, we reexamine this old problem, looking closely at the reversible case. We report a result that challenges the standard wisdom: When the …


Determination Of The Suitability Of Arkansas River Water For Municipal, Industrial And Agricultural Use: Volume 4 Cost Analyses, Joseph Watt, James W. Moore May 1990

Determination Of The Suitability Of Arkansas River Water For Municipal, Industrial And Agricultural Use: Volume 4 Cost Analyses, Joseph Watt, James W. Moore

Arkansas Water Resources Center Technical Reports

Volume IV of the overall report for the project to determine the suitability of the Arkansas River for municipal, agricultural and industrial water supplies contains the cost information calculated using WATER MAID. WATER MAID is an interactive software program for use in calculating treatment plant costs. The software program was developed for the Environmental Protection Agency. The research project was conducted under contract with the Arkansas Soil and Water Conservation Commission.


The Humanistic Aspects Of Mathematics And Their Importance, Philip J. Davis May 1990

The Humanistic Aspects Of Mathematics And Their Importance, Philip J. Davis

Humanistic Mathematics Network Journal

No abstract provided.


Enhancement Of Magneto-Optical Kerr Effects, Liang-Yao Chen, William A. Mcgahan, Z.S. Shan, David J. Sellmyer, John A. Woollam May 1990

Enhancement Of Magneto-Optical Kerr Effects, Liang-Yao Chen, William A. Mcgahan, Z.S. Shan, David J. Sellmyer, John A. Woollam

David Sellmyer Publications

A general expression for the magneto-optical polar Kerr effect is given for a bilayered configuration in which the optical constants of the two media differ. The equation shows that a giant enhancement of the Kerr effect in magneto-optical/metallic bilayers can be expected if the dielectric constants of the two materials are low or are matched well to the other. An explicit equation is also given to calculate the spectral enhancement due to a dielectric overcoating on magnetic substrates. An example is given for SiO-coated Dy/Co compositionally modulated alloys, yielding a good comparison to the experimental results in both the transparent …


Changes To Simulated Fire Behaviour And Societal Benefits After Two Levels Of Thinning In A Mixed-Conifer Wildland-Urban Interface Community, Christopher Dicus Apr 1990

Changes To Simulated Fire Behaviour And Societal Benefits After Two Levels Of Thinning In A Mixed-Conifer Wildland-Urban Interface Community, Christopher Dicus

Natural Resources Management and Environmental Sciences

Potential fire behaviour and various societal benefits (air pollution removal, carbon sequestration, and stormwater runoff) were quantified in a California Sierra mixed-conifer forest in (a) untreated conditions, (b) after removing all understorey trees dbh, and (c) after thinning 50% of the stand's total basal area. Potential fire behaviour was modelled under constant conditions near a hypothetical development by the FARSITE fire behaviour and growth simulator and societal benefits were calculated by CITY green, both GIS-based software applications. Results showed that fire behaviour was considerably moderated by both thinning treatments. Modelled societal benefits, however, were largely unaffected by either treatment, which …


The Annual Meeting Of The Iowa Academy Of Science April 20-21, 1990 [Program, 102nd Meeting], Iowa Academy Of Science Apr 1990

The Annual Meeting Of The Iowa Academy Of Science April 20-21, 1990 [Program, 102nd 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, 14
Symposia Programs --- 15
Poster Session --- 17
Campus Map --- Centerfold
Section Programs --- 22
Agricultural Sciences --- 22
Anthropology --- 25
Botany --- 26
Cellular & Molecular Biology --- 28
Chemistry, Inorganic --- 30
Chemistry, Organic --- 34
Conservation --- 37
Earth Science Teaching --- 39
Elementary Science Teaching --- 40
Engineering --- 42
Geology --- 47
Linguistics --- 48
Nursing --- 49
Physics --- 50
Physiology --- 53
Psychology --- 54
Science Teaching --- 56 …


Polar-Liquid, Derivatized Cyclodextrin Stationary Phases For The Capillary Gas Chromatography Separation Of Enantiomers, Daniel W. Armstrong, Weiyong Li, Chau Dung Chang, Josef Pitha Apr 1990

Polar-Liquid, Derivatized Cyclodextrin Stationary Phases For The Capillary Gas Chromatography Separation Of Enantiomers, Daniel W. Armstrong, Weiyong Li, Chau Dung Chang, Josef Pitha

Chemistry Faculty Research & Creative Works

A new class of hydrophilic, relatively polar liquid, cyclodextrin (CD) derivatives have been used as highly selective chiral stationary phases (CSPs) for capillary gas chromatography (GC). Several possible requirements for liquidity In CD derivatives are discussed. O-(S)-2-Hydroxypropyl derivatives of α-, β-, and γ-cyclodextrlns were synthesized, exclusively characterized, permethylated, and evaluated for enantloselectlvity. Seventy pairs of enantiomers were resolved. They represent a wide variety of structural types and classes of compounds including chlral alkyl amines, amino alcohols, epoxides, pyrans, furans, sugars, dlols, esters, ketones, bicyclic compounds, alcohols, and so on. Many of these compounds were not aromatic and cannot be resolved …


Regional Climate Centers: New Institutions For Climate Service And Climate- Impact Research, Stanley A. Changnon, Peter J. Lamb, Kenneth G. Hubbard Apr 1990

Regional Climate Centers: New Institutions For Climate Service And Climate- Impact Research, Stanley A. Changnon, Peter J. Lamb, Kenneth G. Hubbard

School of Natural Resources: Faculty Publications

In response to the need climate services at the local, state, and regional levels, a national network of regional climate centers has developed. This provides the background to this development, and outlines the functions of the centers and identifies their benefits and beneficiaries. The centers are a source of climate expertise and maintain multifaceted interfaces with the public and private sectors. Each center a) performs services, including the management of the basic data for its region and the delivery of specialized products; b) conducts applied climate studies, including the monitoring of anomalous conditions and the promotin of regional research; and …


Santa Clara Magazine, Volume 32 Number 3, Spring 1990, Santa Clara University Apr 1990

Santa Clara Magazine, Volume 32 Number 3, Spring 1990, Santa Clara University

Santa Clara Magazine

10- SERVICE: THE ULTIMATE STRATEGY A restaurant executive reveals his formula for business success: A Satisfied Customer, Guaranteed. By Timothy W. Firnstahl '65

16 - BLENDED FAMILIES By the year 2000, there will be more stepfamilies than any other kind of family. By Peggy Hernandez '78

20 - NORTHERN IRELAND: A REPORTER'S NOTEBOOK The war between the Catholics and the Protestants is 20 years old and there is no peace in sight. By Kevin Kelly '83

24 - THE FUNERAL OF MICHAEL-JO O'MALLEY A Santa Clara Jesuit writes about a unique ritual he witnessed last summer in County Mayo, Ireland. …


A “Drastic” Evaluation Of The Ground-Water Pollution Potential Of Karst Terrain: Lost River Ground-Water Basin, Warren County, Kentucky, David Baize Apr 1990

A “Drastic” Evaluation Of The Ground-Water Pollution Potential Of Karst Terrain: Lost River Ground-Water Basin, Warren County, Kentucky, David Baize

Masters Theses & Specialist Projects

Karst terrains, such as the Lost River Karst Ground-Water Basin, are extremely vulnerable to ground-water contamination. Seven physical factors: depth to water, recharge, aquifer media, soil media, topography, impact of the vadose zone, and hydraulic conductivity, are evaluated using the DRASTIC system to determine the ground-water pollution potential of the study area. A numerical value is calculated for each of the seven factors, and a map layer for each factor is produced. These layers are then “added” together to produce a DRASTIC ground-water pollution potential map. The effectiveness of each factor in evaluating the pollution potential of karst terrain is …


Water Current, Volume 22, April 1990 Apr 1990

Water Current, Volume 22, April 1990

Water Current Newsletter

Environmental Studies Part of Geography Department, Jeanne Kay
Twentieth Annual Earth Day Observed April 22
NATO Advanced Research Workshop to be Held at UNL in September
First Irrigation Day Held February 22
Just Give Us a Call for Water Seminar Proceedings
Festival Highlights Importance of Nebraska's Groundwater
Prevention Key to Pollution
Assessment Atlas Now Available
Water Conference Council Awards
Agency Cooperation Urged at Water Conference
90s Exciting Times in Water Resources
Nebraska Counties Included in High Plains Irrigation Research
Mid-Nebraska Water Quality Demo Project Combines State and Federal Agencies to Research Irrigation Efficiency
Irrigation Bolsters Nebraska's Economy
First Nebraska Instream …


Introductory Dataperfect® Instruction, Frances Jenson Larsen Apr 1990

Introductory Dataperfect® Instruction, Frances Jenson Larsen

Theses and Dissertations

The project should be used in a beginning computer class. These units contain projects from simple to complex. The first instructional unit uses a database that comes with the DataPerfect® program. The students build and manipulate a small database. Reports are prepared, and finally the students design an original database. These instructional units are intended to be used in a high school classroom with the DataPerfect® computer program. DataPerfect® is a copyrighted program marketed by WordPerfect Corporation of Orem, Utah.


Structure And Morphology Of Magnetite Anaerobically-Produced By A Marine Magnetotactic Bacterium And A Dissimilatory Iron-Reducing Bacterium, N. H. C. Sparks, Stephen Mann, D. A. Bazylinski, D. R. Lovley, H. W. Jannasch, Richard B. Frankel Apr 1990

Structure And Morphology Of Magnetite Anaerobically-Produced By A Marine Magnetotactic Bacterium And A Dissimilatory Iron-Reducing Bacterium, N. H. C. Sparks, Stephen Mann, D. A. Bazylinski, D. R. Lovley, H. W. Jannasch, Richard B. Frankel

Physics

Intracellular crystals of magnetite synthesized by cells of the magnetotactic vibroid organism, MV-1, and extracellular crystals of magnetite produced by the non-magnetotactic dissimilatory iron-reducing bacterium strain GS-15, were examined using high-resolution transmission electron microscopy, electron diffraction and 57Fe Mo¨ssbauer spectroscopy. The magnetotactic bacterium contained a single chain of approximately 10 crystals aligned along the long axis of the cell. The crystals were essentially pure stoichiometric magnetite. When viewed along the crystal long axis the particles had a hexagonal cross-section whereas side-on they appeared as rectangules or truncated rectangles of average dimension, 53 × 35 nm. These findings are explained …


A Review Of Falconry As A Bird-Hazing Technique, William A. Erickson, Rex E. Marsh, Terrell P. Salmon Mar 1990

A Review Of Falconry As A Bird-Hazing Technique, William A. Erickson, Rex E. Marsh, Terrell P. Salmon

Vertebrate Pest Conference Proceedings: 14th (1990)

The use of trained falcons and hawks for dispersing pest birds has been mainly limited to airports in Europe and, to a lesser extent, in North America to prevent bird/aircraft strikes. The peregrine falcon (Falco peregrinus) and the goshawk (Accipiter gentilis) are the raptors used most often. These trained birds can effectively disperse gulls (Larus spp. ) and a variety of other pest bird species, although other bird-scaring methods are often equally or more effective and economical. Because of the scarcity of trained raptors and handlers, their use is limited to special situations such as …


Plague In The U.S.: Present And Future, Allan M. Barnes Mar 1990

Plague In The U.S.: Present And Future, Allan M. Barnes

Vertebrate Pest Conference Proceedings: 14th (1990)

An increasing trend in the frequency of human bubonic plague cases in the United States, the principal sources of human infection, and emerging control techniques are described. Development of an integrated control program involving public health education, citizen participation in plague surveillance, and insecticidal control of flea vectors in response to evidence of plague and potential human exposure substantially reduced human plague cases in a Bernalillo County, New Mexico, hyperendemic plague area. Permethrin 0.5% dust (Pyraperm 455) applied at a rate of 7 g per burrow was found to provide effective control of flea vectors for at least 6 weeks.


Development, Use, And Benefits Of The Animal Damage Control Management Information System, Darlene G. Blaney Mar 1990

Development, Use, And Benefits Of The Animal Damage Control Management Information System, Darlene G. Blaney

Vertebrate Pest Conference Proceedings: 14th (1990)

The United States Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APHIS), Animal Damage Control (ADC) Management Information System (MIS) is in the process of being updated to a relational database format on an IBM-compatible microcomputer. The background of the MIS, the development process, the information that is collected, how the information is used by program managers, and the cost benefits of the automated system are addressed.


The Status Of The Steel Trap In North America, James H. Glass Mar 1990

The Status Of The Steel Trap In North America, James H. Glass

Vertebrate Pest Conference Proceedings: 14th (1990)

This paper will discuss strides taken to limit or eliminate use of the leghold trap and will explore recent trends in the animal rights movement's attack on fur and traps. A current legislative effort in Ohio, which seeks to protect wearers of fur and other animal products, as well as retailers, will be examined. Finally, the outlook as to what the future holds for the anti-trap debate and what we must do as responsible conservationists is discussed.