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Articles 72631 - 72660 of 78713

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Five Marine Resource Management Programs: Innovations And Common Themes, Louisa Rand Moore Jan 1993

Five Marine Resource Management Programs: Innovations And Common Themes, Louisa Rand Moore

Marine Affairs Theses and Major Papers

This paper investigates essential elements of marine resource management programs, particularly how they are initiated and what is needed for their success. The focus of this paper is on management planning for sites where marine resources are still largely intact as opposed to those which are severely disturbed. Planning is aimed at determining carrying capacity of the marine systems and limiting disturbances accordingly. Question for this inquiry were developed from research of a bay in eastern Maine where marine resources have not been severely disturbed, but are vulnerable to over-exploitation due to lack of coordinated management. Using these questions, five …


Computer Methodology For Transportation Agencies To Screen Technologies For Hazardous Waste Remediation, William J. Grenney, Ravi Kumar Penmetsa Jan 1993

Computer Methodology For Transportation Agencies To Screen Technologies For Hazardous Waste Remediation, William J. Grenney, Ravi Kumar Penmetsa

Reports

Executive Summary: Many pathways exist for transportation agencies and other public and private agencies to become responsible for sites contaminated by hazardous wastes. As a reult, agencies frequently face a multitude of lega, regulatory, financial, technical, and health risk problems. When transportation agencies become involved in the remediation of hazardous waste sites, the common practice is to hire consultants and contractors for the clean up process. Because the field of hazardous waste site remediation is changing so rapidly, agency personnel evaluating the consultant's recommendations need to ahve access to the most recent regulatory and remediation information. Early stages of the …


The Interaction Of Sickle Hemoglobin With Phosphatidylserine Vesicles ; Fourier Transform Infrared Spectroscopic Studies Of Human Erythrocyte Spectrin, Cynthia C. Labrake Jan 1993

The Interaction Of Sickle Hemoglobin With Phosphatidylserine Vesicles ; Fourier Transform Infrared Spectroscopic Studies Of Human Erythrocyte Spectrin, Cynthia C. Labrake

Dissertations

No abstract provided.


Polynuclear Mixed-Valence Complexes, David A. Rockcliffe Jan 1993

Polynuclear Mixed-Valence Complexes, David A. Rockcliffe

Dissertations

No abstract provided.


A Facile Route To Allylic Phosphonates Via Base-Catalyzed Isomerization Of The Corresponding Vinyl Phosphonates : Remote Dianions In Synthesis, Synthetic Approaches To The Indolizidines, James J. Kiddle Jan 1993

A Facile Route To Allylic Phosphonates Via Base-Catalyzed Isomerization Of The Corresponding Vinyl Phosphonates : Remote Dianions In Synthesis, Synthetic Approaches To The Indolizidines, James J. Kiddle

Dissertations

No abstract provided.


Trypanosoma (Nannomonas) Congolense: Molecular Characterization Of A New Genotype From Tsavo, Kenya, P. A.O. Majiwa, M. Maina, J. N. Waitumbi, S. Mihok, E. Zweygarth Jan 1993

Trypanosoma (Nannomonas) Congolense: Molecular Characterization Of A New Genotype From Tsavo, Kenya, P. A.O. Majiwa, M. Maina, J. N. Waitumbi, S. Mihok, E. Zweygarth

All Peer-Reviewed Publications

Trypanosoma (Nannomonas) congolense comprises morphologically identical but genetically heterogeneous parasites infective to livestock and other mammalian hosts; three different genotypes of this parasite have been described previously. Restriction enzyme fragment length polymorphisms (RFLPs) in both kinetoplast DNA minicircle and nuclear DNA sequences, and randomly amplified polymorphic deoxyribonucleic acid (RAPD) patterns have been used here to demonstrate the existence of another type of T. (N.) congolense that is genotypically distinct from those that have so far been characterized at the molecular level. A highly repetitive, tandemly arranged DNA sequence and oligonucleotide primers, for use in polymerase chain reaction (PCR) amplification are …


Harpacticoida (Crustacea, Copepoda) From Subterranean Waters Of Bue Marino Cave, Sardinia, And St. Barthélémy Cave, Corsica, And Description Of Three New Species, Vezio Cottarelli, Maria Cristina Bruno Jan 1993

Harpacticoida (Crustacea, Copepoda) From Subterranean Waters Of Bue Marino Cave, Sardinia, And St. Barthélémy Cave, Corsica, And Description Of Three New Species, Vezio Cottarelli, Maria Cristina Bruno

International Journal of Speleology

Three new species of harpacticoid copepods are described and discussed. Nitocrella beatricis n. sp. has been collected in different hyporheic sites in Sardinia and in two caves (Bue Marino cave in Sardinia and St. Barthélémy cave in Corsica); Elaphoidella janas n. sp. and Parastenocaris triphyda n. sp. have been collected only in Bue Marino cave. Some considerations concerning the ecology and biogeography of the three species are also presented.


Comparative Performances Of Non-Visual Food Search In The Hypogean Cyprinid Phreatichthys Andruzzii And In The Epigean Relative Barbus Filamentosus, Roberto Berti, Luca Masciarelli Jan 1993

Comparative Performances Of Non-Visual Food Search In The Hypogean Cyprinid Phreatichthys Andruzzii And In The Epigean Relative Barbus Filamentosus, Roberto Berti, Luca Masciarelli

International Journal of Speleology

The anophthalmic hypogean cyprinid Phreatichthys andruzzii Vinciguerra shows a more efficient food searching behaviour than blinded specimens of the epigean species Barbus filamentosus Cuvier and Valenciennes. This difference seems to be related to a tendency to swim near the bottom of the aquarium and the behavioural stereotypes in food localization and intake. Both in P. andruzzii and in the blinded B. filamentosus food search is guided by chemical stimulation. Other data indicate that mechanical stimulation could play an important role in the feeding behaviour of the hypogean form. The behavioural analogies in food localization between P. andruzzii and the cave …


The Second Occurrence Of The Troglobic Shrimp Macrobrachium Microps Holthuis (Crustacea, Decapoda, Palaemonidae), In Samoa, Alexander J. Bruce, Thomas M. Iliffe Jan 1993

The Second Occurrence Of The Troglobic Shrimp Macrobrachium Microps Holthuis (Crustacea, Decapoda, Palaemonidae), In Samoa, Alexander J. Bruce, Thomas M. Iliffe

International Journal of Speleology

A single example of Macrobrachium from an anchialine lava tube un Upolu, Samoa, is described and illustrated. The specimen is referred to M. microps Holthuis, 1978, but shows some differences that may be of specific value, which are discussed. The troglobic species of Macrobrachium are reviewed.


Habitat Use And Gas Bubble Disease In Southern Cavefish (Typhlichthys Subterraneus), Alex L. S. Schubert, Carl D. Nielsen, Douglas B. Noltie Jan 1993

Habitat Use And Gas Bubble Disease In Southern Cavefish (Typhlichthys Subterraneus), Alex L. S. Schubert, Carl D. Nielsen, Douglas B. Noltie

International Journal of Speleology

In situ observations of habitat use by southern cavefish (Typhlichthys subterraneus) in a Missouri, U.S.A. spring suggest that groundwater discharge and that zones of substrate which have large interstitial spaces that fish can enter may be important components of the species habitat. Such substrates may also facilitate smallscale dispersal. In addition, we document the first recorded case of gas bubble disease in a laboratory-held specimen of this species. Cavefish may be particularly susceptible to this malady, and the conditions under which it occurred are important to avoid should captive maintenance or propagation of this or related species be …


The Cricket Fauna Of Chiapanecan Caves (Mexico): Systematics, Phylogeny And The Evolution Of Troglobitic Life (Orthoptera, Grylloidea, Phalangopsidae, Luzarinae), Laure Desutter-Grandcolas Jan 1993

The Cricket Fauna Of Chiapanecan Caves (Mexico): Systematics, Phylogeny And The Evolution Of Troglobitic Life (Orthoptera, Grylloidea, Phalangopsidae, Luzarinae), Laure Desutter-Grandcolas

International Journal of Speleology

The present study deals with the cavernicolous Grylloidea of Chiapas. It details the composition of this fauna, which belongs exclusively to the Phalangopsid group Amphiacustae, and considers its troglobitic evolution in the methodological framework of Comparative Biology. This method consists in analysing the evolution of biological features in reference to phylogeny, using character state optimization. The material studied comes mostly from Italian biospeological expeditions, but also from the authors work in Mexico, from North American biospeological expeditions achieved in Central America and the West Indies, and from the collections of the Academy of Natural Sciences of Philadelphia, the Museum National …


A Reproductive-Resting Stage In An Harpacticoid Copepod, And The Significance Of Genetically Based Differences Among Populations, D. J. Lonsdale, P. Weissman, Fred C. Dobbs Jan 1993

A Reproductive-Resting Stage In An Harpacticoid Copepod, And The Significance Of Genetically Based Differences Among Populations, D. J. Lonsdale, P. Weissman, Fred C. Dobbs

OES Faculty Publications

Dormancy is an important life-history strategy which allows copepods to increase their fitness by delaying growth and reproduction until harsh environmental conditions have ameliorated. For marine species, the primary strategies identified to date include the production of dormant eggs by shallow-water species, and copepodite overwintering in deep-water species. Herein, we describe a third strategy in which fertilized adult females enter a “reproductive-resting” stage during the late fall that allows them to overwinter and provide a first source of spring naupliar recruitment. This strategy has been observed in the estuarine copepod Coullana canadensis, but may also occur in other species. …


Spatial And Temporal Occurrence Of Spanish Mackerel Scomberomorus Maculatus In Chesapeake Bay, Mark E. Chittenden Jr., Luiz R. Barbieri, Cynthia M. Jones Jan 1993

Spatial And Temporal Occurrence Of Spanish Mackerel Scomberomorus Maculatus In Chesapeake Bay, Mark E. Chittenden Jr., Luiz R. Barbieri, Cynthia M. Jones

OES Faculty Publications

No abstract provided.


Self-Diffusion Studies In Polymer-Solvent Systems By Pulsed-Gradient Spin-Echo Nuclear Magnetic Resonance, R. Allen Waggoner Jan 1993

Self-Diffusion Studies In Polymer-Solvent Systems By Pulsed-Gradient Spin-Echo Nuclear Magnetic Resonance, R. Allen Waggoner

Doctoral Dissertations

"Pulsed gradient NMR techniques have been used to study self-diffusion in polymer solutions. The systems studied include toluene, cyclohexane, ethylbenzene, chloroform, t-butyl acetate, and methyl ethyl ketone in polystyrene; methyl methacrylate in poly(methyl methacrylate); poly(ethylene oxide) in water; and water in biological tissue. The polymer diffusion data are evaluated in terms of scaling theory as they relate to the scaling of the polymer diffusion coefficient with molecular weight. The solvent diffusion data are evaluated with kinetic and free-volume theories. In addition a relatively simple dependence of diffusion coefficient on polymer volume fraction is derived from free-volume theory. The solvent diffusion …


Changes In The Sea-Ice Brine Community During The Spring-Summer Transition, Mcmurdo Sound, Antarctica .2. Phagotrophic Protists, Diane K. Stoecker, Kurt R. Buck, Mary Putt Jan 1993

Changes In The Sea-Ice Brine Community During The Spring-Summer Transition, Mcmurdo Sound, Antarctica .2. Phagotrophic Protists, Diane K. Stoecker, Kurt R. Buck, Mary Putt

OES Faculty Publications

The land-fast sea-ice brine contains a diverse phagotrophic protist assemblage consisting of < 5 mum heterotrophic flagellates, Cryothecomonas spp., heterotrophic dinoflagellates, and heterotrophic and mixotrophic ciliates. Fine-scale horizontal spatial variability is a feature of this assemblage; samples taken within 1 m of each other can be dominated by different heterotrophic protists. Many of the larger heterotrophic protists found in the brine are also found in the water column. The photosynthetic ciliate Mesodinium rubrum is also common. In mid to late austral spring, the heterotrophic assemblage accounts for ca 10% of the total protist biomass in the brine and is dominated by Cryothecomonas spp. This flagellate …


Benthic Microalgal Production At Stellwagen Bank, Massachusetts Bay, Usa, Lawrence B. Cahoon, Guy R. Beretich Jr., Carrie J. Thomas, Amy M. Mcdonald Jan 1993

Benthic Microalgal Production At Stellwagen Bank, Massachusetts Bay, Usa, Lawrence B. Cahoon, Guy R. Beretich Jr., Carrie J. Thomas, Amy M. Mcdonald

OES Faculty Publications

Benthic microalgal chlorophyll a and production were measured at 3 sites at Stellwagen Bank, a cold temperate continental shelf habitat in Massachusetts Bay, USA, during August 1991. Benthic microalgal chlorophyll a averaged 39.8 Mg M-2, vs average integrated phytoplankton chlorophyll a of 25.9 mg m-2. Gross benthic microalgal production, measured by oxygen exchange in clear and opaque benthic chambers, averaged 20.9 mg C m-2 h-1. This production was supported by average daily light fluxes to the bottom that never exceeded 1 % of surface incident radiation and were as low as 4.7 μE …


Instability Waves In The Gulf Stream Front And Its Thermocline Layer, Sang-Ki Lee Jan 1993

Instability Waves In The Gulf Stream Front And Its Thermocline Layer, Sang-Ki Lee

OES Theses and Dissertations

Linear instability calculations were carried out on a three layer Gulf Stream front model in an attempt to elucidate the interaction of the thermocline layer with surface slopewater shoreward of the front. The basic state is geostrophic balance and constant potential vorticity in the two active layers, but the perturbations are ageostrophic. The flow is found to be unstable to long wave perturbations, the wavelength of the most unstable wave to be of order 10 radii of deformation. The instability is mainly baroclinic, 75-85% of the energy supply to the growing perturbation coming from basic flow potential energy. Calculated wavelengths …


Mechanistic Studies On The Preparation Of The Hantzsch’S Base From Ethyl Acetoacetate And Chloromethylmethyl Ether, Huo-Jin Hsieh Jan 1993

Mechanistic Studies On The Preparation Of The Hantzsch’S Base From Ethyl Acetoacetate And Chloromethylmethyl Ether, Huo-Jin Hsieh

Dissertations and Theses @ UNI

Dihydropyridines, which were first studied by Hantzsch in 1882, now bear his name. A new synthesis of Hantzsch 's base, 2,6-dimethyl-3,5-dicarboethoxy-l ,4- dihydropyridine (lb), was discovered. The preparation of Hantzsch's base (lb) from new starting materials, ethyl acetoacetate (3) and chloromethylmethyl ether (4), was described. Ethyl acetoacetate was reacted with sodium amide in liquid ammonia followed by chloromethylmethyl ether to form the 2,6-dimethyl-3,5-dicarboethoxy1,4-dihydropyridine (lb) in 84% overall yield. Compound (lb) was further identified by its oxidation to the corresponding pyridine, 2,6-dimethyl-3,5-dicarboethoxypyridine ( 11 b) by glacial acetic acid. A mechanism for the formation of the compound ( 1 b) was …


The Weakest Bond: Experimental Observation Of Helium Dimer, Fei Luo, George C. Mcbane, Geunsik Kim, Clayton F. Giese, W. Ronald Gentry Dec 1992

The Weakest Bond: Experimental Observation Of Helium Dimer, Fei Luo, George C. Mcbane, Geunsik Kim, Clayton F. Giese, W. Ronald Gentry

Peer Reviewed Articles

Helium dimer ion was observed after electron impact ionization of a supersonic expansion of helium with translational temperature near 1 mK. The dependence of the ion signal on source pressure, distance from the source, and electron kinetic energy was measured. The signal was determined to arise from ionization of neutral helium dimer.


Water Current, Volume 24, December 1992 Dec 1992

Water Current, Volume 24, December 1992

Water Current Newsletter

Seminar Series to Feature Global Perspective
Report from the Director
Argentina, Brazil Toured by Group from Nebraska
Czech Water Specialists Enumerate Contamination Problems
UNL Environmental Specialists Impressed by Hungarians
Foreign Influences on Nebraska Water Law
Trade, Environment, and Development, Tied Together in U.S. Trade Policy
Slovakian Grad Student Studies Aquaculture Here; Wants to Establish Fish Farm in Czechoslovakia
EARTH with Nebraska Connections Trains Agriculturists
La Mancha Plateau Aquifer Stressed by Intensive Irrigation
Hungarian Research Says Their Nitrogen Fertilizer Use Down
What's New?
Irrigation Association Centennial Spawns State Water-History Chronicle
Director of International Drought Information Center Receives Award
Dates to Use


Inventory Of Rare Plant Species In The Pine Ridge Area Of Nebraska (Dawes And Sioux County, Nebraska), Michael I. Fritz, Joyce Philips Hardy, Steven B. Rolfsmeier Dec 1992

Inventory Of Rare Plant Species In The Pine Ridge Area Of Nebraska (Dawes And Sioux County, Nebraska), Michael I. Fritz, Joyce Philips Hardy, Steven B. Rolfsmeier

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

The purpose of this project was to conduct a systematic inventory of rare plant species on the Pine Ridge District of the Nebraska National Forest. The objective of the inventory was to locate rare plant occurrences and compile information on their location, status and any possible threats. Four areas within the Pine Ridge District were identified as priority areas for the inventory fieldwork. The four tracts included the Soldier Creek Wilderness Area, a tract encompassing the East and West Ash Creek drainages, a middle unit tract, and a tract which straddles U.S. Highway 385 and encompasses a number of timber …


The Probe, Issue 128 - December 1992 Dec 1992

The Probe, Issue 128 - December 1992

The Probe: Newsletter of the National Animal Damage Control Association

Contents:

Reflections On An Onerous Deed
CALENDAR OF UPCOMING EVENTS
Coyote Urine Translocated by Flora
PETA Indictments Expected Soon
Plague Claims Bobcat Hunter
Colorado Voters Ban Spring Hunt; Arizonans Defeat Trapping Ban
Charter Member Says Good-Bye
Probe Should Be Advocate for ADC Activities
Bill Fitzwater III
Next Issue Jan/Feb
NADCA Renewals and Donations
New Logo Chosen for NADCA!


The Prairie Naturalist Volume 24, No.4 December 1992 Dec 1992

The Prairie Naturalist Volume 24, No.4 December 1992

The Prairie Naturalist

NEW VASCULAR PLANT RECORDS FOR NORTIl DAKOTA ▪ B. L. Heidel, A. J. Duxbury, W.T. Barker, and J. R. Challey

GROWTH OF BLUEGILLS AND YELLOW PERCH IN SOUTH DAKOTA WATERS ▪ D.w. Willis, J.P. Lott, C.S. Guy, and D.O. Lucchesi

SEASONAL VARIATION IN SAMPLING DATA FOR WALLEYE AND SAUGER COLLECTED WITH GILL NETS FROM LAKE SAKAKAWEA, NORTH DAKOTA ▪ S.W. Mero andD.W. Willis

OBSERVATIONS ON NESTING OF THE AMERICAN BITTERN IN NORTIlWEST MINNESOTA ▪ W D. Svedarsky

FOOD HABITS OF MOURNING DOVES IN EAST CENTRAL SOUTH DAKOTA ▪ J.T. Van't Hul and J.A. Jenks

DISTRIBUTION OF TIlE PYGMY SHREW IN …


Correction Of Chromatic Aberration With An Electron Mirror, Michael Stewart Mauck Dec 1992

Correction Of Chromatic Aberration With An Electron Mirror, Michael Stewart Mauck

Dissertations and Theses

The theoretical basis for using electron mirrors as correctors of chromatic aberration is presented and an experimental verification of correction of chromatic aberration is demonstrated. A hyperbolic electrostatic electron mirror operating in its converging range and at unity magnification was used as a corrector. A novel separating system with deflections taking place at image planes was developed to implement the mirror without impairing the resolution. Correction was demonstrated in an electron optical probe system. The chromatic aberration was measured by means of the shadows cast by a fine mesh placed near the final image. The experimental method and equipment are …


The Influence Of Alfalfa Root Structure On Plains Pocket Gopher Damage And Behavior, Bruce A. Jasch Dec 1992

The Influence Of Alfalfa Root Structure On Plains Pocket Gopher Damage And Behavior, Bruce A. Jasch

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

No abstract provided.


Generalization And Parallelization Of Messy Genetic Algorithms And Communication In Parallel Genetic Algorithms, Laurence D. Merkle Dec 1992

Generalization And Parallelization Of Messy Genetic Algorithms And Communication In Parallel Genetic Algorithms, Laurence D. Merkle

Theses and Dissertations

Genetic algorithms (GA) are highly parallelizable, robust semi- optimization algorithms of polynomial complexity. The most commonly implemented GAs are 'simple' GAs (SGAs). Reproduction, crossover, and mutation operate on solution populations. Deceptive and GA-hard problems are provably difficult for simple GAs. Messy GAs (MGA) are designed to overcome these limitations. The MGA is generalized to solve permutation type optimization problems. Its performance is compared to another MGA's, an SGA's, and a permutation SGA's. Against a fully deceptive problem the generalized MGA (GMGA) consistently performs better than the simple GA. Against an NP-complete permutation problem, the GMGA performs better than the other …


Etann Hardware Implementation For Radar Emitter Identification, James B. Calvin Jr. Dec 1992

Etann Hardware Implementation For Radar Emitter Identification, James B. Calvin Jr.

Theses and Dissertations

This study investigated classification of 30 radar emitters with 16 signal features using Intel's 80170NX chip, the Electronically Trainable Analog Neural Network (ETANN). Software tools were developed to characterize the ETANN sigmoidal transfer function for use in a custom simulator, known as Neural Graphics. Neural Graphics operates on a Silicon Graphics workstation. The Intel Neural Network Training System simulators were used in early experiments, but were found to be inefficient in training on data used in this research. Using a modified Neural Graphics simulator, single chip and multi-chip experiments were performed to provide benchmark results prior to performing chip-in-loop training. …


Face Recognition With Neural Networks, Dennis L. Krepp Dec 1992

Face Recognition With Neural Networks, Dennis L. Krepp

Theses and Dissertations

This study investigated neural networks for face verification and classification. The research concentrated on developing a neural network based feature extractor and/or classifier to perform authorized user verification in a realistic work environment. Recognition accuracy, system assumptions, training time, and execution time were analyzed to determine the feasibility of a neural network approach. Data was collected using a camcorder and two segmentation schemes: manual segmentation and motion-based, automatic segmentation. Data consisted of over 2000. 32x32 pixel, 8 bit gray scale images of 52 subjects; each subject had two to ten days worth of images collected. Several training and test sets …


An In Vitro Study Comparing The Conventional Step-Back Instrumentation Technique To A Combination Step-Back/Ultrasonic Technique, James A. Eberhardt Dec 1992

An In Vitro Study Comparing The Conventional Step-Back Instrumentation Technique To A Combination Step-Back/Ultrasonic Technique, James A. Eberhardt

Loma Linda University Electronic Theses, Dissertations & Projects

Cleaning and shaping the root canal system is an important phase of endodontic therapy, and must be performed thoroughly and completely if successful root canal therapy is to be expected. A number of investigators have compared different methods of cleaning and shaping of the root canal system. The purpose of this study was to compare the effectiveness of the conventional step-back technique with that of a combination step-back/ultrasonic technique. This combination technique is a modification of the conventional step-back technique using an ultrasonic instrument alternately with hand instrumentation. Utilizing 40 canals from extracted human mandibular molar teeth with a curvature …


Landman Development And Evaluation In The Wallatin Creek Catchment - Final Report, Alan Hawkins Dec 1992

Landman Development And Evaluation In The Wallatin Creek Catchment - Final Report, Alan Hawkins

Natural resources published reports

The aim of the project was to evaluate and further develop the Landman farm planning procedure. The Wallatin creek catchment in the Kellerberrin shire of Western Australia was selected. This catchment is typical of a large area of the wheatbelt of Western Australia.

The landman farm planning procedure has a goal of sustainable farming. The outcome of the procedure is farm layout and farm management plans. The procedure however has components of personal development, technology transfer and development of problem solving skills at both individual and group levels. The process steps are; definition of objectives, collection of information, problem or …