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Molecular Techniques Reveal Wide Phyletic Diversity Of Heterotrophic Microbes Associated With Discodermia Spp. (Porifera: Demospongiae), Jose V. Lopez, Peter J. Mccarthy, Kathleen E. Janda, Robin Willoughby, Shirley A. Pomponi Jun 1999

Molecular Techniques Reveal Wide Phyletic Diversity Of Heterotrophic Microbes Associated With Discodermia Spp. (Porifera: Demospongiae), Jose V. Lopez, Peter J. Mccarthy, Kathleen E. Janda, Robin Willoughby, Shirley A. Pomponi

Marine & Environmental Sciences Faculty Articles

Sponges are well known to harbor large numbers of heterotrophic microbes within their mesohyl. Studies to determine the diversity of these associated microbes have been attempted for only a few shallow water species. We cultured various microorganisms from several species of Discodermia collected from deep water using the 'Johnson-Sea-Link' manned submersibles, and characterised them by standard microbiological identification methods. Characterisation of a small proportion (ca. 10%) of the total and potential eubacterial isolate collection with molecular systematics techniques revealed a wide diversity of microbes. Phylogenetic analyses of 32 small subunit (SSU) 16S-like rRNA gene sequences from different micorbes indicated high …


Thermodynamic And Binding Studies Of Ligand-Carcinogen Dna Targets, Qianying Liang May 1999

Thermodynamic And Binding Studies Of Ligand-Carcinogen Dna Targets, Qianying Liang

Seton Hall University Dissertations and Theses (ETDs)

No abstract provided.


Molecular Characterization Of Soil Ammonia-Oxidizing Bacteria Based On The Genes Encoding Ammonia Monooxygenase, Jose Javier Alzerreca May 1999

Molecular Characterization Of Soil Ammonia-Oxidizing Bacteria Based On The Genes Encoding Ammonia Monooxygenase, Jose Javier Alzerreca

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ammonia-oxidizing bacteria (AOB) are chemolithotrophs that oxidize ammonia/ammonium to nitrite in a two-step process to obtain energy for survival. AOB are difficult to isolate from the environment and iso lated strains may not represent the diversity in soil. A genetic database and molecular tools were developed based on the ammonia monooxygenase (AMO) encoding genes that can be used to assess the diversity of AOB that exist in soil and aquatic environments without the isolation of pure cultures. The amo genes have excellent potential as molecular markers; since AMO is only found in the AOB and is essential for their metabolism, …


Hunting And Social Behaviour Of Leopard Seals (Hydrurga Leptonyx) At Seal Island, South Shetland Islands, Antarctica, Lisa M. Hiruki, Michael K. Schwartz, Peter L. Boveng Jan 1999

Hunting And Social Behaviour Of Leopard Seals (Hydrurga Leptonyx) At Seal Island, South Shetland Islands, Antarctica, Lisa M. Hiruki, Michael K. Schwartz, Peter L. Boveng

United States Department of Commerce: Staff Publications

The hunting behavior of leopard seals Hydrurga leptonyx was monitored opportunistically at Seal Island, South Shetland Islands, during the austral summers from 1986/87 to 1994/95. Leopard seals used several methods to catch Antarctic fur seal pups Arctocephalus gazella and chinstrap penguins Pygoscelis antarctica, and individuals showed different hunting styles and hunting success. One to two leopard seals per year were responsible for an average of 60% of observed captures of fur seal pups. Leopard seals preyed on penguins throughout the summer, but preyed on fur seal pups only between late December and mid-February. Hunting behavior differed significantly between different …


The Probe, Issue 195 – December 1998 Dec 1998

The Probe, Issue 195 – December 1998

The Probe: Newsletter of the National Animal Damage Control Association

Rabies -- Mike Dwyer, NADCA Director, Great Lakes Region
Position Available: Wildlife Biologist, JFK Airport
NWCO Organization Forms in Calif.
Update on Idaho Wolf Damage
Wildlife Wins in UT, OH, MN, Loses in CA
Schmidt to be Appointed NADCA President
Rabies in Bats: The following article was authored by Kate Lewandowski and is reprinted with permission from "SCWDS Briefs," the quarterly newsletter of the Southeastern Cooperative Wildlife Disease Study, The University of Georgia, Athens, GA.

Bird-Strike Committee -USA Abstracts

CANADA GEESE AND SNOW GEESE – REASSESSING TRADITIONAL PARADIGMS FOR MANAGEMENT -- Robert Blohm, U.S. Fish & Wildlife Service, Migratory Bird …


1998 Platte River Basin Ecosystem Symposium Proceedings Jan 1998

1998 Platte River Basin Ecosystem Symposium Proceedings

Water Current Newsletter

No abstract provided.


Book Review Of Paleolimnology Of Europeanmaar Lakes By J. F.W. Negendank & B. Zolitschka (Eds)., J. Platt Bradbury Jan 1998

Book Review Of Paleolimnology Of Europeanmaar Lakes By J. F.W. Negendank & B. Zolitschka (Eds)., J. Platt Bradbury

United States Geological Survey: Staff Publications

This book represents a collection of papers presented at a symposium in May, 1991 on the formation and paleolimnology of European maar lakes. Paleolimnological discussions embrace maar lake deposits of late Quaternary to early Tertiary age in Germany, France and Italy. The goal of the symposium and its outgrowth, this book, is to develop a funding initiative to study, core and analyze the deposits of these remarkable depositional systems.


Biomineralization Of Magnetic Iron Minerals In Bacteria, Richard B. Frankel, Dennis A. Bazylinski, Dirk Schϋler Jan 1998

Biomineralization Of Magnetic Iron Minerals In Bacteria, Richard B. Frankel, Dennis A. Bazylinski, Dirk Schϋler

Physics

Magnetotactic bacteria orient and migrate along magnetic field lines. This ability is based on a submicron assembly of single-magnetic domain iron mineral particles that elegantly solves the problem of how to construct a magnetic dipole that is large enough to be oriented in the geomagnetic field at ambient temperature, yet fit inside a micron-sized cell. The solution is based on the ability of the bacteria to accumulate high concentrations of iron, and control the deposition, size and orientation of a specific iron mineral at specific locations in the cell.


Kinetic Studies Of The Thermal Decomposition Of Di- And Tri-Organotin Derivatives Of 1-Nitroso-2-Naphthol, Saqib Ali, Moazzam H. Bhatti, Sohail Mahmood, Muhammad Mazhar, M. Saleem Khalid, Nazar Hussain Jan 1998

Kinetic Studies Of The Thermal Decomposition Of Di- And Tri-Organotin Derivatives Of 1-Nitroso-2-Naphthol, Saqib Ali, Moazzam H. Bhatti, Sohail Mahmood, Muhammad Mazhar, M. Saleem Khalid, Nazar Hussain

Turkish Journal of Chemistry

The di- and tri-organotin complexes of general formula R$_2$SnL$_2$ and R$_3$SnL where R = C$_4$H$_9$, C$_6$H$_5$, C$_6$H$_5$CH$_2$, C$_6$H$_{11}$ and L=1-nitroso-2-naphthol, were subjected to thermal decomposition by means of thermogravimetry (TG). The decomposition occurred in steps and the kinetics of every set of reactions were determined using the method described by Coats and Redfern. These results were analysed to establish the decomposition kinetics and hence to calculate activation energies. The activation energies were also determined by applying the method described by Horowitz, which yielded comparable results.


Velocity Estimation Via A Neural Network Enhanced By Classical Detection Algorithms, Zeki Berk Hamşioğlu Oct 1997

Velocity Estimation Via A Neural Network Enhanced By Classical Detection Algorithms, Zeki Berk Hamşioğlu

Electrical & Computer Engineering Theses & Dissertations

The goal of this research is to show how to solve a velocity estimation problem using a neural network connected to an array of sensors. Motivated by biological studies involving insect vision, the neural network utilized is a member of a class of shunting neural networks. When an object moves across the face of the sensor array, the neural network's pulse response is first temporally located using classical M-ary detection techniques. Both the deterministic and stochastic cases are considered. Then the network's pulse response is post-processed via an existing velocity estimation algorithm based on a Volterra series model of the …


Microgravity Effects On Water Flow And Distribution In Unsaturated Porous Media, Scott B. Jones, Dani Or Jun 1997

Microgravity Effects On Water Flow And Distribution In Unsaturated Porous Media, Scott B. Jones, Dani Or

Utah Space Grant Consortium

Several aspects of the physical processes of liquid flow and distribution within partially saturated porous media are altered in the reduced gravity conditions (microgravity) of orbiting spacecraft. The objectives of this study were to simulate and test measured flow and distribution in porous media from a microgravity environment using conventional capillary flow theory. Two past microgravity experiments studying water supply and uptake in porous media took place on a U.S. space shuttle, titled ASC-1, and on the Russian space station Mir, titled Greenhouse-2. Data from microgravity and ground experiments were simulated using similar physical flow models by elimination of the …


Physiologically-Based Vision Modeling Applications And Gradient Descent-Based Parameter Adaptation Of Pulse Coupled Neural Networks, Randy P. Broussard Jun 1997

Physiologically-Based Vision Modeling Applications And Gradient Descent-Based Parameter Adaptation Of Pulse Coupled Neural Networks, Randy P. Broussard

Theses and Dissertations

In this research, pulse coupled neural networks (PCNNs) are analyzed and evaluated for use in primate vision modeling. An adaptive PCNN is developed that automatically sets near-optimal parameter values to achieve a desired output. For vision modeling, a physiologically motivated vision model is developed from current theoretical and experimental biological data. The biological vision processing principles used in this model, such as spatial frequency filtering, competitive feature selection, multiple processing paths, and state dependent modulation are analyzed and implemented to create a PCNN based feature extraction network. This network extracts luminance, orientation, pitch, wavelength, and motion, and can be cascaded …


Determination Of Selected Hydrocarbon Concentrations In Reformate Using Near Infrared Spectroscopy, Roy Roger Bledsoe Jr. Jan 1997

Determination Of Selected Hydrocarbon Concentrations In Reformate Using Near Infrared Spectroscopy, Roy Roger Bledsoe Jr.

Theses, Dissertations and Capstones

Near infrared spectroscopy was used as a quantitative technique employing multiple linear regression and partial least squares regression for determining the concentration of hydrocarbon groups and individual hydrocarbons present in reformate, a refinery process stream. Models were generated for total aromatics, benzene, toluene, total xylenes and individual xylene isomers, ethylbenzene, total paraffins, n-hexane, n-heptane, total isoparaffins, isopentane, 2-methylhexane, total naphthenes, methylcyclopentane, and total olefins. Some models are being used with an on-line instrument to constantly monitor a reformate stream as it leaves the reforming unit, with a standard error of performance of 0.118 volume percent for the prediction …


1997 Platte River Basin Ecosystem Symposium Proceedings Jan 1997

1997 Platte River Basin Ecosystem Symposium Proceedings

Water Current Newsletter

No abstract provided.


Ionic Interaction Studies Of Bovine Copper, Zinc-Superoxide Dismutase, Hanan A. Hasan Jan 1997

Ionic Interaction Studies Of Bovine Copper, Zinc-Superoxide Dismutase, Hanan A. Hasan

Dissertations

No abstract provided.


Microwave Plasma Chemical Vapor Deposited Diamond Tips For Scanning Tunneling Microscopy, Sacharia Albin, Jianli Zheng, John B. Cooper, Weihai Fu, Arnel C. Lavarias Jan 1997

Microwave Plasma Chemical Vapor Deposited Diamond Tips For Scanning Tunneling Microscopy, Sacharia Albin, Jianli Zheng, John B. Cooper, Weihai Fu, Arnel C. Lavarias

Electrical & Computer Engineering Faculty Publications

Diamond microparticles were grown on etched tungsten wires using a microwave plasma-assisted chemical vapor deposition process. The apexes on cubo-octahedral particles bound by {100} and {111} facets were effectively used as tunneling tips for scanning tunneling microscopy. The atomically resolved surface image of highly oriented pyrolytic graphite was acquired. Tunneling characteristics revealed a higher electron emission from the diamond tips than that from the platinum–iridium tips. The same diamond tips were used to produce surface indentation and its image. © 1997 American Institute of Physics.


How The Regulated Community Views Regulation To Protect Living Resources: The Endangered Species Act, Biological Diversity, And Ecosystem Management, Steven P. Quarles Jun 1996

How The Regulated Community Views Regulation To Protect Living Resources: The Endangered Species Act, Biological Diversity, And Ecosystem Management, Steven P. Quarles

Biodiversity Protection: Implementation and Reform of the Endangered Species Act (Summer Conference, June 9-12)

21 pages.

Contains footnotes.


An Overview Of The Endangered Species Act, Michael J. Brennan Jun 1996

An Overview Of The Endangered Species Act, Michael J. Brennan

Biodiversity Protection: Implementation and Reform of the Endangered Species Act (Summer Conference, June 9-12)

25 pages.


The Lipooligosaccharides Of Haemophilus Ducreyi Are Highly Sialylated, William Melaugh, A A. Campagnari, B W. Gibson Jan 1996

The Lipooligosaccharides Of Haemophilus Ducreyi Are Highly Sialylated, William Melaugh, A A. Campagnari, B W. Gibson

Chemistry Faculty Publications

The major lipooligosaccharides of the sexually transmitted pathogen Haemophilus ducreyi 35000 have been previously found to terminate in N-acetyllactosamine and sialyl-N-acetyllactosamine, Neu5Ac alpha 2-->3Gal beta 1-->4GlcNAc (W. Melaugh, N. J. Phillips, A. A. Campagnari, M. V. Tullius, and B. W. Gibson, Biochemistry 33: 13070-13078, 1994). In this study, mass spectrometry and composition analyses have shown that the lipooligosaccharides from three other H. ducreyi strains also contain N-acetyllactosamine and are highly sialylated (approximately 30 to 50%), although one African strain was found to contain neither of these structural features.


Spring 1996, Nsu Oceanographic Center Jan 1996

Spring 1996, Nsu Oceanographic Center

Currents

No abstract provided.


An Annotated Checklist Of The Spiders Of Northwestern Iowa And The Loess Hills Of Western Iowa, Barbara J. Abraham Jan 1996

An Annotated Checklist Of The Spiders Of Northwestern Iowa And The Loess Hills Of Western Iowa, Barbara J. Abraham

Journal of the Iowa Academy of Science: JIAS

Spiders were collected by the author from various habitats in 16 counties of northwestern Iowa and the loess hills of western Iowa during the summers of 1985 and 1990-1992. Additional donated specimens from the same region in 1981and1989 were identified by the author. Twenty-three families, 92 genera and 184 species have been identified.


Na+-H+ Exchange And Na+-Li+ Exchange In Human Erythrocytes: An Nmr Investigation, Yuling Chi Jan 1996

Na+-H+ Exchange And Na+-Li+ Exchange In Human Erythrocytes: An Nmr Investigation, Yuling Chi

Dissertations

No abstract provided.


Nectarivorous Feeding Mechanisms In Bats, Patricia W. Freeman Sep 1995

Nectarivorous Feeding Mechanisms In Bats, Patricia W. Freeman

School of Natural Resources: Faculty Publications

Cranio-dental characteristics are quantified between micro- and megachiropteran nectarivores and compared with microchiropteran animalivores, frugivores, and megachiropteran frugivores. Microchiropteran nectarivores share many characteristics with megachiropteran nectarivores and frugivores, but differ in having a long, narrow head. Megachiropterans have wide zygomata, which would allow for more jaw musculature. Diminutive cheekteeth are characteristic of nectarivory in both suborders, but both have relatively large canines. Teeth in nectarivores can occupy as little as a tenth of the palatal area compared to nearly two-thirds in microchiropteran animalivores. The proportion that the dilambdodont stylar shelf occupies of molars in microchiropteran nectarivores can be as much …


Biological Processes: Relationships Between Earthworms And Soil Temperature, Edwin C. Berry, Jerry K. Radke Jan 1995

Biological Processes: Relationships Between Earthworms And Soil Temperature, Edwin C. Berry, Jerry K. Radke

Journal of the Minnesota Academy of Science

Soil fauna play important roles in many soil processes and conditions which relate to agricultural systems. Earthworms are credited with enhancing soil fertility and soil physical properties by their feeding and burrowing activities. Most research on earthworms has focused on the warmer seasons of the year and relatively little is known about earthworm activity and survival during the portion of the year with frozen soils. Earthworms may survive winter by acclimatization, aestivation, or by burrowing to deeper depths where the soil is not frozen. More research is needed on the fate of earthworms in frozen soils. Suggested research areas include: …


Management Of The Omani Abalone Haliotis Mariae: An Integrated Policy, Kadhim M. Al-Bahrani Jan 1995

Management Of The Omani Abalone Haliotis Mariae: An Integrated Policy, Kadhim M. Al-Bahrani

Marine Affairs Theses and Major Papers

The Sultanate of Oman is a small coastal nation with a maritime history, regional trade and fisheries exploitation. Among those fishery industries is Oman's coastal abalone fishery, which command the highest prices per unit of weight among the other marine living resources. This study analyzes the fishery's biological aspects, structure, socioeconomic, policies, and management practices in an attempt to provide an understanding of the prime parameters, that in turn could be utilized for sound management purposes. it also provides a description of an integrated development and management policy for the abalone fishery. Finally, it is hoped that this research will …


Spatio-Temporal Pattern Recognition Using Hidden Markov Models, Kenneth H. Fielding Jun 1994

Spatio-Temporal Pattern Recognition Using Hidden Markov Models, Kenneth H. Fielding

Theses and Dissertations

A new spatio-temporal method for identifying 3D objects found in 2D image sequences is presented. The Hidden Markov Model technique is used as a spatio-temporal classification algorithm to identify 3D objects by the temporal changes in observed shape features. A new information theoretic argument is developed that proves identifying objects based on image sequences can lead to higher classification accuracies than single look methods. A new distance measure is proposed that analyzes the performance of Hidden Markov Models in a multi-class pattern recognition problem. A three class problem identifying moving light display objects provides experimental verification of the sequence processing …


Application Of A Maximum Likelihood Processor To Acoustic Backscatter For The Estimation Of Seafloor Roughness Parameters, Zoi-Heleni Michalopoulou, Christian De Moustier May 1994

Application Of A Maximum Likelihood Processor To Acoustic Backscatter For The Estimation Of Seafloor Roughness Parameters, Zoi-Heleni Michalopoulou, Christian De Moustier

Center for Coastal and Ocean Mapping

Maximum likelihood (ML) estimation is used to extract seafloor roughness parameters from records of acoustic backscatter. The method relies on the Helmholtz–Kirchhoff approximation under the assumption of a power‐law roughness spectrum and on the statistical modeling of bottom reverberation. The result is a globally optimum, highly automated technique that is a useful tool in the context of seafloor classification via remote acoustic sensing. The general geometry of the Sea Beam bathymetric system is incorporated into the design of the ML processor in order to make it applicable to real acoustic data collected by this system. The processor is initially tested …


Clean Lakes Assistance Program For Lake Nacimiento, Thomas J. Rice, David H. Chipping, Norman L. Eatough, Royden Nakamura, Daniel Bigley Apr 1994

Clean Lakes Assistance Program For Lake Nacimiento, Thomas J. Rice, David H. Chipping, Norman L. Eatough, Royden Nakamura, Daniel Bigley

Earth and Soil Sciences

No abstract provided.


Study Of Existing Information Concerning Water Quality Within Lake Mead, Vicki Scharnhorst, Southern Nevada Water Authority Feb 1994

Study Of Existing Information Concerning Water Quality Within Lake Mead, Vicki Scharnhorst, Southern Nevada Water Authority

Publications (WR)

The purpose of Task 010A15M of the Southern Nevada Water Authority (SNWA) Treatment and Transmission Facility (TTF) contract is to conduct a study of existing information concerning water quality within Lake Mead and identify additional water quality studies that are needed to supplement existing data. The objective of this task is not to discuss treatability of the raw water source; this is addressed by Task 010A18M, "Define Water Treatment Requirements." In addition, a narrative on the effect of pending Safe Drinking Water Act amendments and a determination of treated water quality goals is included in Task 010A16M, "Review Safe Drinking …


Use Of Pyocin To Select A Haemophilus Ducreyi Variant Defective In Lipooligosaccharide Biosynthesis, A A. Campagnari, R Karalus, M A. Apicella, William Melaugh, A J. Lesse, B W. Gibson Jan 1994

Use Of Pyocin To Select A Haemophilus Ducreyi Variant Defective In Lipooligosaccharide Biosynthesis, A A. Campagnari, R Karalus, M A. Apicella, William Melaugh, A J. Lesse, B W. Gibson

Chemistry Faculty Publications

Haemophilus ducreyi, a cause of genital ulcer disease in developing countries, appears to facilitate the heterosexual transmission of the human immunodeficiency virus in Africa. Despite an increase in studies of this gram-negative human pathogen, little is known about the pathogenesis of chancroid. Our studies have shown that the lipooligosaccharides (LOS) of H. ducreyi may play an important role in ulcer formation. Monoclonal antibody and mass spectrometric analyses identified a terminal trisaccharide present on H. ducreyi LOS that is immunochemically similar to human paragloboside. This epitope is present on the LOS of Neisseria gonorrhoeae, and it may be the site of …