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Mathematical Models Of Tumors And Their Remote Metastases, Carryn Bellomo Apr 1998

Mathematical Models Of Tumors And Their Remote Metastases, Carryn Bellomo

Mathematics & Statistics Theses & Dissertations

Clinical observations and indications in the literature have led us to investigate several models of tumors. For example, it has been shown that a tumor has the ability to send out anti-growth factors, or inhibitors, to keep its remote metastases from growing. Thus, we model the depleting effect of such a growth inhibitor after the removal of the primary tumor (thus removing the source) as a function of time t and distance from the original tumor r.

It has also been shown clinically that oxygen and glucose are nutrients critical to the survival and growth of tumors. Thus, we model …


Explosive Vapor Generation And Sampling In Conjunction With Ion Mobility Spectrometry, Saeed H. Almeer Apr 1998

Explosive Vapor Generation And Sampling In Conjunction With Ion Mobility Spectrometry, Saeed H. Almeer

Chemistry & Biochemistry Theses & Dissertations

The primary objective of this research is to develop an inexpensive and reliable method to generate vapor pulses of explosives using 2,4,6-trinitrotoluene TNTl for proof of concept. A secondary objective is to demonstrate the use of the vapor generator in various applications keeping in mind potential field scenarios involving explosives. A vapor generator/collector system was developed which gives reproducible pulses of TNT vapors at nanogram levels. The use of this technology was demonstrated in evaluating different surfaces for vapor adsorption of TNT in conjunction with ion mobility spectrometry as the primary analytical tool. Of the materials examined, Teflon was by …


Reaction-Diffusion Models Of Cancer Dispersion, Kim Yvette Ward Apr 1998

Reaction-Diffusion Models Of Cancer Dispersion, Kim Yvette Ward

Mathematics & Statistics Theses & Dissertations

The phenomenological modeling of the spatial distribution and temporal evolution of one-dimensional models of cancer dispersion are studied. The models discussed pertain primarily to the transition of a tumor from an initial neoplasm to the dormant avascular state, i.e. just prior to the vascular state, whenever that may occur. Initiating the study is the mathematical analysis of a reaction-diffusion model describing the interaction between cancer cells, normal cells and growth inhibitor. The model leads to several predictions, some of which are supported by experimental data and clinical observations $\lbrack25\rbrack$. We will examine the effects of additional terms on these characteristics. …


Material Evaluation By Pulsed Diode Laser Optoacoustics, Xiaodong Xu Apr 1998

Material Evaluation By Pulsed Diode Laser Optoacoustics, Xiaodong Xu

Electrical & Computer Engineering Theses & Dissertations

Pulsed diode laser optoacoustic diagnostics were carried out to characterize solid sample materials. The apparatus developed is compact, portable, cost-effective and therefore very promising for both industrial as well as laboratory applications. To our knowledge, this is the first time that optoacoustic characterization and measurement have been performed with a diode laser. The method was successfully applied to measure the thickness of a multilayer structure non-intrusively. Internal cracks of the material were detected by this technique.

A theory for optoacoustic signal generation, propagation and detection is given. A numerical analysis technique is developed to solve for the expected signal. In …


Results Of The City Of Tampa Surface Water Compliance Monitoring Program For The Year 1997 And Examination Of Long-Term Water Quality And Biological Indicator Trends In Hillsborough Bay, City Of Tampa Department Of Sanitary Sewers Mar 1998

Results Of The City Of Tampa Surface Water Compliance Monitoring Program For The Year 1997 And Examination Of Long-Term Water Quality And Biological Indicator Trends In Hillsborough Bay, City Of Tampa Department Of Sanitary Sewers

Reports

This report is submitted to Florida Department of Environmental Regulation (FDER) to satisfy the requirements set forth in specific condition No. 14 of Hookers Point WWTP permit No. D029-184532B. The report is based on data obtained by the City of Tampa (COT) compliance water quality monitoring program approved under construction permit DC29-152799 and the report also includes examination of long-term trends for water quality parameters and biological indicators collected by the City of Tampa Bay Study Group and the Environmental Protection Commission of Hillsborough County (EPC).


Synthesis, Molecular Structure, And Reactivity Of Dinuclear Copper(Ii) Complexes With Carboxylate-Rich Coordination Environments, Richard C. Holz, John M. Bradshaw, Brian Bennett Mar 1998

Synthesis, Molecular Structure, And Reactivity Of Dinuclear Copper(Ii) Complexes With Carboxylate-Rich Coordination Environments, Richard C. Holz, John M. Bradshaw, Brian Bennett

Physics Faculty Research and Publications

The dinucleating ligand N,N‘-(2-hydroxy-5-methyl-1,3-xylylene)bis(N-(carboxymethyl)glycine) (CH3HXTA) has been used to synthesize the dinuclear Cu(II) bis(pyridine) complex Na[Cu2(CH3HXTA)(Py)2]·1.5(1,4-dioxane) (Na(1)):  triclinic space group P1̄ (a = 12.550(3) Å, b = 13.413(3) Å, c = 13.540(4) Å, α = 117.12(2)°, β = 104.70 (2)°, and γ = 92.13(2)°). The structure shows two distinct distorted square pyramidal Cu(II) centers with each Cu(II) ion bound by two carboxylate oxygen atoms, one amine nitrogen atom, a phenolate oxygen atom, and one pyridine nitrogen atom. The Cu--Cu separation is 3.531 Å, …


A Cell Cycle-Regulated Adenine Dna Methyltransferase From Caulobacter Crescentus Processively Methylates Gantc Sites On Hemimethylated Dna, Anthony J. Berdis, Irene Lee, James K. Coward, Craig Stephens, Rachel Wright, Lucy Shapiro, Stephen J. Benkovic Mar 1998

A Cell Cycle-Regulated Adenine Dna Methyltransferase From Caulobacter Crescentus Processively Methylates Gantc Sites On Hemimethylated Dna, Anthony J. Berdis, Irene Lee, James K. Coward, Craig Stephens, Rachel Wright, Lucy Shapiro, Stephen J. Benkovic

Chemistry Faculty Publications

The kinetic properties of an adenine DNA methyltransferase involved in cell cycle regulation of Caulobacter crescentus have been elucidated by using defined unmethylated or hemimethylated DNA (DNAHM) substrates. Catalytic efficiency is significantly enhanced with a DNAHM substrate. Biphasic kinetic behavior during methyl incorporation is observed when unmethylated or DNAHM substrates are used, indicating that a step after chemistry limits enzyme turnover and is most likely the release of enzyme from methylated DNA product. The enzyme is thermally inactivated at 30°C within 20 min; this process is substantially decreased in the presence of saturating concentrations of DNAHM, suggesting that the enzyme …


Observations Of Nocturnal Foraging In The Double-Crested Cormorant, D. Tommy King, J. Brent Harrel, Brian Dorr, David Reinhold Mar 1998

Observations Of Nocturnal Foraging In The Double-Crested Cormorant, D. Tommy King, J. Brent Harrel, Brian Dorr, David Reinhold

United States Department of Agriculture Wildlife Services: Staff Publications

Double-crested Cormorants (Phalacrocorax auritus) are normally considered a diurnal species. Here we describe cormorants foraging nocturnally in an oxbow lake in Mississippi. We have observed this behavior only once during 30 capture attempts over seven years.


Relationship Between Ecosystem Productivity And Photosynthetically Active Radiation For Northern Peatlands, S. E. Frolkin, J.L. Bubier, T.R. Moore, T. Ball, L.M. Bellisario, A. Bhardwaj, P. Carroll, P.M. Crill, Peter M. Lafleur, J.H. Mccaughey, N.T. Roulet, A. E. Suyker, S.B. Verma, J.M. Waddington, G.J. Whiting Mar 1998

Relationship Between Ecosystem Productivity And Photosynthetically Active Radiation For Northern Peatlands, S. E. Frolkin, J.L. Bubier, T.R. Moore, T. Ball, L.M. Bellisario, A. Bhardwaj, P. Carroll, P.M. Crill, Peter M. Lafleur, J.H. Mccaughey, N.T. Roulet, A. E. Suyker, S.B. Verma, J.M. Waddington, G.J. Whiting

School of Natural Resources: Faculty Publications

We analyzed the relationship between new ecosystem exchange of carbon dioxide (NEE) and irradiance (as photosynthetic photon flux density of PPFD), using published and unpublished data that have been collected during midgrowing season for carbon balance studies at seven peatlands in North America and Europe. NEE measurements included both eddy-correlation tower and clear, static chamber methods, which gave very similar results. Data were analyzed by site, as aggregated data set for all peatland type (bog, poor fen, rich fen, and all fens) and as a single aggregated data set for all peatlands. In all cases, a fit with a rectangular …


Hunting And Exposure: Estimating Risk And Future Use At Nuclear Production Sites, Jessica Sanchez, Joanna Burger Mar 1998

Hunting And Exposure: Estimating Risk And Future Use At Nuclear Production Sites, Jessica Sanchez, Joanna Burger

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

The authors advocate specific criteria for informed decisions about the future use - of contaminated nuclear sites. They also compare the implications of official recommendations for one site with results from a study.


The Value Of Preventing Cryptosporidium Contamination, Patricia Kocagil, Nadia Demarteau, Ann Fisher, James S. Shortle Mar 1998

The Value Of Preventing Cryptosporidium Contamination, Patricia Kocagil, Nadia Demarteau, Ann Fisher, James S. Shortle

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

The authors evaluate the need for preventing illnesses and fatalities caused by Cryptospiridium contamination of water supplies based on the impacts of recent and likely future outbreaks.


Inventory And Characterization Of The Riparian Zone Of The Current And Jacks Fork Rivers, Jonathan Lyon, Cynthia L. Sagers Mar 1998

Inventory And Characterization Of The Riparian Zone Of The Current And Jacks Fork Rivers, Jonathan Lyon, Cynthia L. Sagers

Arkansas Water Resources Center Technical Reports

The ecological, recreational, and economic value of the 134 mile (216 km) riparian corridor within the Ozark National Scenic Riverways (ONSR) is of great interest to land managers and conservationists. Recent interest in applying ecosystem management to forest systems has necessitated a fresh look at the tools and methods in use to assess existing patterns of plant community structure and diversity. The purpose and objective of the study described in this report was to initiate a series of vegetation studies that could be integrated with existing research and management infonnation on the riparian vegetation in the ONSR. Defining the compositional …


The Efficacy Of Glue Traps Against Wild Populations Of House Mice, Mus Domesticus, Rutty, Robert M. Corrigan Mar 1998

The Efficacy Of Glue Traps Against Wild Populations Of House Mice, Mus Domesticus, Rutty, Robert M. Corrigan

Vertebrate Pest Conference Proceedings: 18th (1998)

Field research was conducted from Purdue University during 1991 to 1993 to examine some aspects of the efficaciousness of the various types of glue traps against wild populations of house mice. The research was conducted in agricultural and livestock buildings containing various infestation levels of mice. Tests compared the capture and escape rates of glue boards vs. trays, covered vs. uncovered glue traps, and glue traps vs. snap traps, and multiple catch curiosity traps. Observational work, via night vigils, was also conducted to note the behavioral response of mice to glue surfaces, including the behavioral aspects of mice neutralizing glue …


Management Of Conflicts Between Urban Coyotes And Humans In Southern California, Rex O. Baker, Robert M. Timm Mar 1998

Management Of Conflicts Between Urban Coyotes And Humans In Southern California, Rex O. Baker, Robert M. Timm

Vertebrate Pest Conference Proceedings: 18th (1998)

An apparent increase in coyote-human conflicts, notably attacks on humans, demonstrates that such incidents are not rare in California. The authors discuss coyote attacks on 53 humans, resulting in 21 instances of human injury, over the last decade. These illustrate repeated, predictable pre-attack coyote behavior patterns. Specific changes in human environments and in human behavior that have contributed to coyote attacks are discussed. Case histories of attacks reveal contributing factors and suggest appropriate corrective and preventive actions. Padded leghold traps have been the most effective and efficient tool in removing problem coyotes and changing the behavior of coyotes to fear …


The Prairie Naturalist Volume 30, No.1 March 1998 Mar 1998

The Prairie Naturalist Volume 30, No.1 March 1998

The Prairie Naturalist

WATERFOWL FOODS OF CULTIVATED WILD RICE PADDIES IN NORTHWEST MINNESOTA ▪ J. T. Huseby, W. Po Cymbaluk, A. J. Melvie, W. D. Svedarsky, and R. D. Crawford

ICHTHYOFAUNA IN STREAMS OF THE MISSOURI RIVER DRAINAGE, WYOMING ▪ T. M. Patton, W. A. Hubert, and F. J. Rahel

Aphthona nigriscutis LARVAL DENSITIES IN CAMPBELL COUNTY, SOUTH DAKOTA ▪ M. A. Brinkman and S. A. Clay

DIETS OF BISON SOCIAL GROUPS ON TALLGRASS PRAIRIE IN OKLAHOMA ▪ B. R. Coppedge and J. H. Shaw

NUTRIENT AND ENERGETIC CHARACTERISTICS OF GRASSHOPPERS OF DIFFERENT LIFE STAGES ▪ R. J. Robel, C. A. Desjardins, and …


The Probe, Issue 186 - March 1998 Mar 1998

The Probe, Issue 186 - March 1998

The Probe: Newsletter of the National Animal Damage Control Association

CONTENTS:
NWCO Trade Assn. Proposed
NADCA Board Acts on NWCO Concerns
NWCO Concerns Heard
One View of W.C.T. Seminar
CALENDAR OF UPCOMING EVENTS
Back Issues of The Probe
Moving? Let Grant Know!
Postdoc / Postgraduate Position Available
Proceedings Available
State NWCO Organizations Grow
Video Review: Bird Barrier's Product Installation Video Tape Series.
More Reports From 4th Annual Conference of The Wildlife Society


Ecological Tax Reform, Robert Costanza, Steve Bernow, Herman E. Daly, Robert Degennaro, Paul Hawken Mar 1998

Ecological Tax Reform, Robert Costanza, Steve Bernow, Herman E. Daly, Robert Degennaro, Paul Hawken

Institute for Sustainable Solutions Publications and Presentations

Provides an overview detailing the benefits of ecological tax reform. What ecological tax reform would include; Origin of ecological taxes; Implementation in the United States and Europe; Specifics on an ecological tax reform proposal; The need to phase in tax reforms gradually.


Double Photoionization Of Helium, James A.R. Samson, Wayne C. Stolte, Z. X. He, Y. Lu, J. N. Cutler, R. J. Bartlett Mar 1998

Double Photoionization Of Helium, James A.R. Samson, Wayne C. Stolte, Z. X. He, Y. Lu, J. N. Cutler, R. J. Bartlett

Chemistry and Biochemistry Faculty Research

The cross sections for double photoionization of helium and the ratios of double to single ionization have been measured from the double-ionization threshold to 820 eV. The results are in very good agreement with several recent calculations.


Involving Others: Towards An Ethical Concept Of Risk, Christoph Rehmann-Sutter Mar 1998

Involving Others: Towards An Ethical Concept Of Risk, Christoph Rehmann-Sutter

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

Dr. Rehman-Sutter argues for a juridical concept of risk as it relates to an ethic of care. He also contrasts his view with traditional economic risk analysis.


Reflections On Metacomputing, The Bond View, Dan C. Marinescu, Ladislau Bölöni Mar 1998

Reflections On Metacomputing, The Bond View, Dan C. Marinescu, Ladislau Bölöni

Department of Computer Science Technical Reports

No abstract provided.


Graphical User Interface Design For The X-Ray Crystallography Data Processing Program - Scaling, K. C. Van Zandt, Dan C. Marinescu, Robert Bolotovsky, Michael Rossman Mar 1998

Graphical User Interface Design For The X-Ray Crystallography Data Processing Program - Scaling, K. C. Van Zandt, Dan C. Marinescu, Robert Bolotovsky, Michael Rossman

Department of Computer Science Technical Reports

No abstract provided.


The National Wildlife Research Center: Providing Innovative Solutions To Human–Wildlife Conflicts Mar 1998

The National Wildlife Research Center: Providing Innovative Solutions To Human–Wildlife Conflicts

United States Department of Agriculture Wildlife Services: Staff Publications

Welcome to the National Wildlife Re search Center (NWRC), the primary research facility within the Wildlife Services (WS) program of the U.S. Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS). NWRC provides scientific information on wildlife, its habitat, and its relationship to agriculture and public safety. Here at the Center and at our nine field stations, specialists conduct scientific inquiries into the problems of wildlife damage and look for solutions to these problems.


A Study On The Uptake And Voltammetric Determination Of Trace Heavy Metals In The Treated Wastewater In Abu-Dhabi Area, Salem Rashed Salem Al-Hassani Mar 1998

A Study On The Uptake And Voltammetric Determination Of Trace Heavy Metals In The Treated Wastewater In Abu-Dhabi Area, Salem Rashed Salem Al-Hassani

Theses

Wastewater reuse has a positive and negative environmental impacts and possibly it can have an important role to play in water resources management, as a substituent for freshwater in irrigation. However, the presence of the toxic heavy metals in domestic sewage and in industrial effluents discharge to sewers, wastewater can create unacceptable health and environmental risks. Therefore, the present work includes the determination of the toxic heavy metals in some treated wastewater samples collected from Abu-Dhabi area using polarographic and voltammetric techniques. Differential pulse polarography and anodic stripping voltammetry are well established techniques for trace determination of heavy metals content …


Games To Teach Mathematical Modelling, James A. Powell, Jim S. Cangelosi, Ann M. Harris Mar 1998

Games To Teach Mathematical Modelling, James A. Powell, Jim S. Cangelosi, Ann M. Harris

Mathematics and Statistics Faculty Publications

We discuss the use of in-class games to create realistic situations for mathematical modelling. Two games are presented which are appropriate for use in post-calculus settings. The first game reproduces predator-prey oscillations and the second game simulates disease propagation in a mixing population. When used creatively these games encourage students to model realistic data and apply mathematical concepts to understanding the data.


Identification And Characterization Of Gfrα-3, A Novel Co-Receptor Belonging To The Glial Cell Line-Derived Neurotrophic Receptor Family, Carolyn A. Worby, Quinn Vega, Hanna H.J. Chao, Audrey F. Seasholtz, Robert C. Thompson, Jack E. Dixon Feb 1998

Identification And Characterization Of Gfrα-3, A Novel Co-Receptor Belonging To The Glial Cell Line-Derived Neurotrophic Receptor Family, Carolyn A. Worby, Quinn Vega, Hanna H.J. Chao, Audrey F. Seasholtz, Robert C. Thompson, Jack E. Dixon

Department of Mathematics Faculty Scholarship and Creative Works

A new family of neuronal survival factors comprised of glial cell line- derived neurotrophic factor (GDNF) and neurturin has recently been described (Kotzbauer, P. T., Lampe, P. A., Heuckeroth, R. O., Golden, J.P., Creedon, D. J., Johnson, E. M., Jr., and Milbrandt, J. (1997) Nature 384, 467-470). These molecules, which are related to transforming growth factor-β, are important in embryogenesis and in the survival of distinct neuronal populations. These molecules signal through a novel receptor system that includes the Ret receptor tyrosine kinase, a ligand (i.e. GDNF or neurturin), and an accessory glycosyl-phosphatidylinositol-linked molecule that is responsible for high affinity …


The Probe, Issue 185 – February 1998 Feb 1998

The Probe, Issue 185 – February 1998

The Probe: Newsletter of the National Animal Damage Control Association

Animal Rights Groups Should Give Shelters Money, by Susan E. Paris
In Memoriam--Obituary: Norton R. Miner
From the President -- Robert H. Giles, Jr., President, NADCA
Job Announcements: 1. Coordinator, Isabela Project, Galapagos National Park Service; 2. Leader of Eradication Program Galapagos National Park Service
Brochure Provides Advice to Ranchers on Wolf Livestock Kills
Seattle Coyote Gets A Lift
Radio Says "No Thanks" to Fund
Oregon Mink Farms Attacked
Rabies Down, Tapeworms Up in European Foxes

More Reports From the 4th Annual Conference of The Wildlife Society:
Linking Spatial Heterogeneity and Social Behavior to Carnivore Population Dynamics: Development and Evaluation …


Water Center, Volume 30, No. 1, February 1998 Feb 1998

Water Center, Volume 30, No. 1, February 1998

Water Current Newsletter

Resource Institute Working to Restore Native Prairies and Wetlands
From the Director: Water Conference, Seminar Series, USGS Grants
The Clean Water Act: A Twenty-Five Year Retrospective
CWA Has Positive Effects, But Future Cloudy
Still Time to Register for "Nebraska Water 2000"
Study Shows Risk of Animal Waste
Investigators Focus Attention on Community Drinking Water Disinfection
Water News Briefs
GW Foundation's Festival Expedition
Nominations for Haverstick Award
EPA Publications on Line
Source Water Assessment Program
E-Answers
Groundwater University and Groundwater Grad School


Environmental Variability Effects On Marine Fisheries: Four Case Histories, Eileen E. Hofmann, T. M. Powell Feb 1998

Environmental Variability Effects On Marine Fisheries: Four Case Histories, Eileen E. Hofmann, T. M. Powell

CCPO Publications

The changing nature of marine fisheries requires management approaches that recognize and include ecosystem and environmental effects. Therefore, we review some examples of exploited fishery stocks in which environmental control is a major contributor to structuring the abundance and distribution of the stock. Four examples, taken from studies of northern cod (Gadus morhua), cod and haddock (Melanogrammus aeglefinus) larvae, the eastern oyster (Crassostrea virginica), and Antarctic krill (Euphausia superba), are given that clearly illustrate environmental control on the fishery. From these examples, we argue that future management strategies for exploited fisheries must include effects of environmental variability. In particular, management …


Environmental Management For Animal-Based Industries : Dairy Farm Effluent, Western Australia Agriculture Western Australia Bunbury Regional Office., Dairy Industry Nutrient Strategy Working Group (W.A.) Feb 1998

Environmental Management For Animal-Based Industries : Dairy Farm Effluent, Western Australia Agriculture Western Australia Bunbury Regional Office., Dairy Industry Nutrient Strategy Working Group (W.A.)

Bulletins 4000 -

The effluent which collects around dairies and their associated feeding facilities should be regarded as a resource to be retained and used on the farm, rather than a waste product for disposal.

These guidelines aim to assist dairy farmers plan effluent management systems which are practical, as well as easy to install and manage, while also being acceptable to the agencies and authorities given the responsibility of protecting the environment. .


Biodegradation Of Pah Contaminated Soil And Sludge Using Non-Ionic Surfactants, Seema Narula Jan 1998

Biodegradation Of Pah Contaminated Soil And Sludge Using Non-Ionic Surfactants, Seema Narula

Dissertations

Polycyclic aromatic hydrocarbons (PAHs) are one of the most prevalent environmental pollutants contaminating a large number of industrial and Superfund sites. Low solubility and sorption to solid surfaces limit biodegradation rates of PAHs in the environment. Bioremediation of these compounds have been previously tested with partial success. In the present study, aerobic biodegradation of three PAHs (fluorene, phenanthrene, and pyrene) has been studied in shaker flasks, batch fermenter, and bioslurry reactor, in the presence of non-ionic surfactants. A mixed bacterial culture derived from both a refinery sludge and an activated sludge was used as the seed population in the degradation …