Physical Sciences and Mathematics Commons^™

The Synthesis Of Azure B Derivatives: Potential Pro-Drugs For Photodynamic Therapy, Carla M. Edwards

Dissertations

No abstract provided.

Development Of A Unique Photothermal Interferometer, Michael Henry

Dissertations

No abstract provided.

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

Dissertations

No abstract provided.

1996 Platte River Basin Ecosystem Symposium Proceedings

Water Current Newsletter

No abstract provided.

The Closed Geodesic Problem For Compact Riemannian 2-Orbifolds, Joseph E. Borzellino, Benjamin G. Lorica

Mathematics

In this paper it is shown that any compact Riemannian 2-orbifold whose underlying space is a (compact) manifold without boundary has at least one closed geodesic.

Cooperative Assistance For Remote Robot Supervision, Robin R. Murphy, Erika Rogers

Computer Science and Software Engineering

This paper describes current work on a cooperative tele-assistance system for semi-autonomous control of mobile robots. This system combines a robot architecture for limited autonomous perceptual and motor control with a knowledge-based operator assistant which provides strategic selection and enhancement of relevant data. It extends recent developments in artificial intelligence in modeling the role of visual interactions in problem solving for application to an interface permitting the human and remote to cooperate in cognitively demanding tasks such as recovering from execution failures, mission planning, and learning. The design of the system is presented, together with a number of exception-handling scenarios …

A Study Of Visual Reasoning In Medical Diagnosis, Erika Rogers

Computer Science and Software Engineering

The purpose of this paper is to describe experimental work conducted in the area of diagnostic radiology,with an emphasis on how perception and problem solving interact in this type of task. This work was part of a larger project whose goals included the development of an information-processing model of visual interaction,and the subsequent design of an intelligent cooperative assistant for this domain.

Verbal protocol data was collected from eight radiologists (six residents and two experts) while they examined seven different computer-displayed chest x-rays. A brief overview of the methodology and analysis techniques is presented, together with specific results from one …

An Improved Synthesis Of 2-(Hydroxymethyl)Indene, Hasan Palandoken, William T. Mcmillen, Michael H. Nantz

Chemistry and Biochemistry

No abstract provided.

Comptel Measurements Of Mev Gamma-Ray Burst Spectra, R M. Kippen, James M. Ryan, A Connors, Mark L. Mcconnell, C Winkler, L O. Hanlon, V Schonfelder, J Greiner, M Varendorff, W Collmar, W Hermsen, L Kuiper

Space Science Center

We present results from the on-going spectral analysis of gamma-ray bursts measured by the COMPTEL instrument in its main Compton “Telescope” observing mode (0.75–30 MeV). Thus far, 18 bursts have been analyzed from three years (April 1991–April 1994) of observations. The time-averaged spectra of these events above 1 MeV are all consistent with a simple power law model with spectral index in the range 1.5–3.5. Exponential, thermal bremsstrahlung and thermal synchrotron models are statistically inconsistent with the burst sample, although they can adequately describe some of the individual burst spectra. We find good agreement between burst spectra measured simultaneously by …

Hard X‐Ray Polarimetry Of Solar Flares With Batse, Mark L. Mcconnell, D J. Forrest, W T. Vestrand, M Finger

Space Science Center

We describe a technique for measuring the polarization of hard X‐rays from solar flares based on the angular distribution of that portion of the flux which is scattered off the top of the Earth’s atmosphere. The scattering cross section depends not only on the scatter angle itself, but on the orientation of the scatter angle with respect to the incident polarization vector. Consequently, the distribution of the observed albedo flux will depend on the direction and the polarization properties (i.e., the level of polarization and polarization angle) of the source. Since the albedo component can represent a relatively large fraction …

Table Of Contents Volume Seven, Number One, Winter 1996, Risk Editorial Board

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

Table of contents for the journal RISK: Health, Safety & Environment (ISSN: 1073-8673)

Dioxin: Reassessing The Risk, Linda-Jo Schierow

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

Dr. Schierow briefly summarizes the status of a draft Environmental Protection Agency report reassessing the appropriate treatment of dioxin and describes ongoing intra- and extramural reviews of the reassessment.

Predicting Future Sources Of Mass Toxic Tort Litigation, Jeffrey A. Foran, Bernard D. Goldstein, John A. Moore, Paul Slovic

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

The authors describe the efforts of an expert working group to identify potential sources, over the next five to ten years, of future mass litigation and report on the group's consensus conclusions.

Fish Advisories: Useful Or Difficult To Interpret?, Joanna Burger, Michael Gochfeld

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

The authors note that fish and shellfish offer significant exposure to environmental toxins but find that consumer knowledge and other factors may limit efforts to control risk in urban populations.

Why Do We Worry About Trace Poisons?, Allan Mazur

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

Dr. Mazur relates how protests by the political left against nuclear tests and by the political right against fluoridation set the stage for Silent Spring to move the public toward being concerned about latent risks.

Termolecular Proton Transfer Reactions Assisted By Ionic Hydrogen Bond Formation: Reactions Of Aromatic Cations With Polar Molecules, George M. Daly, Michael Mautner, Y. B. Pithawalla, M. Samy El-Shall

Chemistry Publications

We present a new method that applies resonant‐two‐photon ionization to generate reactant ions selectively in the source of a high‐pressure mass spectrometer (R2PI‐HPMS) for kinetic and equilibrium studies. Applications to reactions that would be obscured otherwise in a complex system are illustrated in mixtures of benzene with polar solvent molecules (S). We observe a novel type of proton transferreactions from C₆H₆ ^+• to two S molecules where S=CH₃CN, CH₃OH, C₂H₅OH and CH₃COOC₂H₅, and from C₆H₅CH₃ ^+• to two …

Highly Reactive Form Of Copper And Reagents Thereof, Reuben D. Rieke

Chemistry Department: Faculty Publications

A novel Zerovalent copper species and an organocopper reagent are disclosed. The Zerovalent copper species is directly produced by reaction of a reducing agent with a combination of copper(I) cyanide or halide and an alkali metal halide salt. The organocopper reagent resulting from the reaction of the zerovalent copper species and an organic compound having one or more stable anionic leaving groups is a stable reagent that will not significantly homocouple and under controlled conditions tolerates the presence of nitrile, epoxide, imine, enone, ketone, ester, allyl and benzyl groups within the organo radical. The reagent can be controlled so that …

An Interdisciplinary Water Quality Curriculum For Middle School Students, Barbara Michelle Cleveland

All Graduate Projects

An interdisciplinary curriculum correlating water quality with the disciplines of physical science and mathematics for 6th grade middle school students was developed. Literature examined indicates that the opportunity to explore key concepts and significant issues using an integrated approach provided greater opportunity to formulate meaningful connections between disciplines studied and that achievement was enhanced. The Learning units were developed for use at Wilson Middle School in Yakima, Washington.

A Guide For Extending Nature Lessons At The Yakima Arboretum, Marilou Cori Kinder

All Graduate Projects

The importance of providing a hands on natural environment curriculum was examined. Sources from 1938-1996 were found supporting the importance of such a curriculum. A search was conducted on the availability of a natural habitat curriculum that used a local resource. The search discovered the Yakima Arboretum had seven areas of interest along with a packet of brief lesson suggestions. These lessons were extended to include classroom activities that would provide students with background knowledge prior to a field trip to the Arboretum.

Tourism: Who Needs It?, Joan S. Remington, Marcel R. Escoffier

Hospitality Review

Is tourism economically beneficial? If so, who benefits? How much of the money generated through tourism can be channeled into other projects so desperately needed by the community without harming the local tour market? Will tourism continue to grow forever, or is there an end in sight? The authors discuss how tourism will change in approaching the next century: and how people will change if tourism is to remain such an important economic facto

Substitution Reactions Of (C5ph5)Cr(Co)3: Structural, Electrochemical, And Spectroscopic Characterization Of (C5ph5)Cr(Co)2l, L = Pme3, Pme2ph, P(Ome)3, D. John Hammack, Mills M. Dillard, Michael Castellani, Arnold L. Rheingold, Anne L. Rieger, Philip H. Rieger

Chemistry Faculty Research

The radical complex (C₅Ph₅)Cr(CO)₃ reacts with small, neutral, monodentate Lewis bases (PMe₃, PMe₂Ph, P(OMe)₃) in THF at −78 °C (PMe₂Ph reacts at ambient temperature) to yield the monomeric substitution products (C₅Ph₅)Cr(CO)₂L·THF as thermally stable solids. Electrochemical and spectroscopic data are provided. An X-ray crystal structure of the hemisolvate (C₅Ph₅)Cr(CO)₂PMe₃·0.5THF was obtained. Frozen-solution ESR spectra of (C₅Ph₅)Cr(CO)₂L in toluene are comparable to those of other low-spin d^{5 …}

Late Pleistocene Interactions Of East And West Antarctic Ice-Flow Regimes: Evidence From The Mcmurdo Ice Shelf, Thomas B. Kellogg, Terence J. Hughes, Davida E. Kellogg

Earth Science Faculty Scholarship

We present new interpretations of deglaciation in McMurdo Sound and the western Ross Sea, with observationally based reconstructions of interactions between East and West Antarctic ice at the last glacial maximum (LGM), 16 000, 12 000, 8000 and 4000 sp. At the LGM? East Antarctic ice from Mulock Glacier split, one branch turned westward south of Ross Island but the other branch rounded Ross Island before flowing southwest into McMurdo Sound. This flow regime, constrained by an ice saddle north of Ross Island, is consistent with the reconstruction of Stuiver and others (1981a). After the LGM, grounding-line retreat was most …

Ice-Core Glaciochemical Reconnaissance In Inland West Antarctica, Karl J. Kreutz, Paul Andrew Mayewski, Mark S. Twickler, Sallie I. Whitlow

Earth Science Faculty Scholarship

To date, the highest resolution ice cores have come from Greenland [the U.S. Greenland Ice Sheet Project 2 (GISP2) and European Greenland Ice Core Project (GRIP)]. The ability to determine annual layering in these cores over at least the past 50,000 years has allowed the reconstruction of a detailed environmental history covering major glacial and interglacial climatic events (e.g., Mayewski et aI. 1994; O'Brien et al. 1995). Although these cores have significantly advanced our understanding of paleoclimatic change in the Northern Hemisphere, questions remain as to whether the two hemispheres have responded synchronously to climate forcing through time. Determining the …

Evaluating Bighorn Habitat: A Landscape Approach, William C. Dunn

United States Bureau of Land Management: Staff Publications

This technical note describes a method that incorporates a landscape approach with the use of Geographic Information Systems (GIs) to measure habitat and impacts for Rocky Mountain and desert bighorn sheep and to rank potential transplant sites. A landscape approach, in which habitat is viewed from a large-scale perspective as an assemblage of patches, is used because: (1) bighorn habitat is naturally patchy due to the affinity of bighorn for terrain that is both open and mountainous; (2) fragmentation (i.e., increased patchiness) often is the most severe consequence of human disturbance; and (3) the proximity and distribution of neighboring bighorn …

On A Differential Analog Of The Prime-Radical And Properties Of The Lattice Of Radical Differential Ideals In Associative Differential Rings, D. Hadjiev, F. Çallialp, A. Eden

Turkish Journal of Mathematics

In this paper we prove the following results: (1) For any assosiative differential ring with the unit we introduce a differential analog of the prime-radical and describe it; (2) any maximal differential ideal of a Ritt algebra is prime; (3) The lattice of radical differential ideals satisfies the condition of infinite \cap- distributivity.

The Possibility Of Flux Flow Spectroscopy, S. E. Barnes, J. L. Cohn, F. Zuo

Physics Articles and Papers

A novel spectroscopic technique applicable to the study of spin excitations in magnetic materials is described. The probe frequency and wave vector are determined by the moving Abrikosov flux lattice of a type II superconductor in the mixed state. The feasibility of employing oxide superconductors and relevant material parameters are discussed.

1x27 Cartoons About Science, Mark S. Coyne

Plant and Soil Sciences Faculty Book Gallery

A tongue-in-cheek look at the world of natural science.

Theoretical Hei Line Intensities In Gaseous Nebulae: Ngc 1976, 6572 And Ic 4997, J. B. Kingdon, Gary J. Ferland

Physics and Astronomy Faculty Publications

Smits has recently calculated theoretical He I intensities for a large number of lines for conditions appropriate to gaseous nebulae. These are likely to remain the definitive calculations for some time to come. A comparison of these line ratios with observed values in three nebulae reveals some discrepancies. We show that these discrepancies are reduced when collisional effects from the metastable 2₃S level are included, and that it is not necessary to invoke an unknown depopulation mechanism for the He I2₃S level.

Infiltration Of Fecal Bacteria Through Soils: Timing And Tillage Effects, Mark S. Coyne, C. S. Stoddard, John H. Grove, William O. Thom

Soil Science News and Views

Land-applying animal wastes potentially exposes humans and animals to fecal pathogens, either by direct contact with soil and produce, or via ground water contamination. Some of these organisms are Salmonella, certain pathogenic Escherichia coli strains, protozoa such as Cryptosporidium and Giardia, and enteric viruses. Whether soil adequately filters these pathogens before they reach ground water depends on the interaction of porosity, texture, depth, water content, rainfall intensity and duration, and soil management.

No-Tilling Corn Into Hairy Vetch: Fertilizer Nitrogen Substitution Without Penalty Due To Delayed Planting, H. M. Saha, John H. Grove

Soil Science News and Views

Previous studies conducted in Kentucky have shown that hairy vetch is an agronomically viable winter legume cover crop for notill corn production. However, to fully realize the benefits of this cover crop it is necessary to allow enough time for it to accumulate biomass and nitrogen (N) before no-till corn is planted. Thus, early corn planting may not always be feasible. Since delaying corn planting after May 15 in Kentucky usually leads to a decline in corn grain yields, the main question addressed in this study (one for which little information was available) was whether the benefits provided by hairy …