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1999

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Full-Text Articles in Physical Sciences and Mathematics

Search For “Quadrupole-Bound” Anions. I, Gennady L. Gutsev, Puru Jena, Rodney J. Bartlett Jan 1999

Search For “Quadrupole-Bound” Anions. I, Gennady L. Gutsev, Puru Jena, Rodney J. Bartlett

Physics Publications

In a classical model, some anions exist due to the attraction between an electron and a molecule’s dipole moment. When the dipole moment is sufficiently large (μcrit>2.5 D), an electron can be trapped. Can a sufficiently large quadrupole moment produce the same effect? To help answer this question, we can search for molecules with a large quadrupole moment and use predictive, ab initio, correlated quantum chemistry methods to assess whether an anion forms and, if it does, to discover its nature. For this purpose, coupled-cluster calculations are reported for the structure and properties of KnClm and KnCl−m (n,m=0–2). …


An Integrated Surface Water Quality Monitoring Program For South Florida Coastal Waters, Ronald Jones, Joseph N. Boyer Jan 1999

An Integrated Surface Water Quality Monitoring Program For South Florida Coastal Waters, Ronald Jones, Joseph N. Boyer

SERC Research Reports

No abstract provided.


Florida Keys National Marine Sanctuary Water Quality Monitoring Project 1999 Annual Report, Ronald Jones, Joseph N. Boyer Jan 1999

Florida Keys National Marine Sanctuary Water Quality Monitoring Project 1999 Annual Report, Ronald Jones, Joseph N. Boyer

SERC Research Reports

No abstract provided.


Long Term Trends In The Water Quality Of Florida Bay (June 1989-Dec. 1999), Joseph N. Boyer, Ronald Jones Jan 1999

Long Term Trends In The Water Quality Of Florida Bay (June 1989-Dec. 1999), Joseph N. Boyer, Ronald Jones

SERC Research Reports

No abstract provided.


Two-Photon Excitation Of Rhenium Metal-Ligand Complexes, Joseph R. Lakowicz, Felix N. Castellano, Ignacy Gryczynski, Zygmunt Gryczynski, Jonathan D. Dattelbaum Jan 1999

Two-Photon Excitation Of Rhenium Metal-Ligand Complexes, Joseph R. Lakowicz, Felix N. Castellano, Ignacy Gryczynski, Zygmunt Gryczynski, Jonathan D. Dattelbaum

Chemistry Faculty Publications

We describe the emission spectral properties of two rhenium metal-ligand complexes with one and two-photon excitation, Re(bpy)2(CO)3Cl and [Re(bpy)(CO)3CH3CN]+, where bpy is 2,2’-bipyridyl and CH3CN is acetonitrile. Similar emission spectra and intensity decay times characteristic of the metal-to-ligand charge transfer state were observed for one- and two-photon excitation. The lifetime and quantum yield of the acetonitrile complex are approximately 14-fold higher than that of the chloride complex. Both complexes display high anisotropies near 0.33 in frozen solution with one-photon excitation. Two-photon excitation results in anisotropies about 40% larger, …


(Ω, Ξ)-Logic: On The Algebraic Extension Of Coalgebraic Specifications, Rolf Hennicker, Alexander Kurz Jan 1999

(Ω, Ξ)-Logic: On The Algebraic Extension Of Coalgebraic Specifications, Rolf Hennicker, Alexander Kurz

Engineering Faculty Articles and Research

We present an extension of standard coalgebraic specification techniques for statebased systems which allows us to integrate constants and n-ary operations in a smooth way and, moreover, leads to a simplification of the coalgebraic structure of the models of a specification. The framework of (Ω,Ξ)-logic can be considered as the result of a translation of concepts of observational logic (cf. [9]) into the coalgebraic world. As a particular outcome we obtain the notion of an (Ω, Ξ)- structure and a sound and complete proof system for (first-order) observational properties of specifications.


Analysis Of Phytoestrogens By High Performance Liquid Chromatography, Anne A. Grippo, Yan Xie, Benjamin L. Rougeau, William V. Wyatt Jan 1999

Analysis Of Phytoestrogens By High Performance Liquid Chromatography, Anne A. Grippo, Yan Xie, Benjamin L. Rougeau, William V. Wyatt

Journal of the Arkansas Academy of Science

Phytoestrogens are biochemicals synthesized in plants which mimic steroidal estrogen activity in mammals. Analysis of these compounds in the legumes which produce them and in body fluids is important to the study of their physiological effects. High pressure liquid chromatography (HPLC) has been found to be an efficient and sensitive method of identification and quantitation of isoflavonoids, one class of phytoestrogen. Here we report the separation of three isoflavonoids, biochanin A, genistein and daidzein using an HPLC system with a Cg reverse phase column and a linear gradient mobile phase containing acetonitrile and acetic acid/water (10/90, v/v) over 60 minutes. …


Importance Of Convection And Damping On Rates Of Convergence For The Lax-Wendroff Method, Joseph Kolibal Jan 1999

Importance Of Convection And Damping On Rates Of Convergence For The Lax-Wendroff Method, Joseph Kolibal

Faculty Publications

It is well known that in solving steady state problems using hyperbolic time-stepping methods the intent is to drive the transients to zero as quickly as possible. In this paper the convergence to steady state of the Lax-Wendroff method applied to solving the equations of gas dynamics is analyzed for the Laval nozzle problem by comparing the relative rates of damping and convection using a linearized eigenmode analysis. This analysis is developed for the simpler isenthalpic system and then extended to the full Euler equations. Finally, this allows a comparison between these systems. For both models, useful analytical information can …


Iowa Academy Of Science 111th Annual Meeting [1999]: Advance Program, Iowa Academy Of Science Jan 1999

Iowa Academy Of Science 111th Annual Meeting [1999]: Advance Program, Iowa Academy Of Science

Iowa Academy of Science Documents

Contains information about the schedule and presentations for the 1999 annual meeting of the Iowa Academy of Science.


Iowa Academy Of Science Membership Directory, 1999-2000, Iowa Academy Of Science Jan 1999

Iowa Academy Of Science Membership Directory, 1999-2000, Iowa Academy Of Science

Iowa Academy of Science Documents

Table of Contents:

Editorial Board, Journal ... 5
Committees ... 6
Sections ... 18
ISTS Regional Directors ... 22
Awards of Merit ... 24
Excellence in Science Teaching Awards ... 25
Past Presidents ... 26
Membership Roster ... 27
Corporate Sponsors ... 70


Characterization And Improvement Of Eos Land Products Using Measurements At Ameriflux Grassland And Wheat Sites In The Arm/Cart Region: Research Annual Performance Report For Period March 1, 1999- February 29, 2000., E. A. Walter-Shea, S. B. Verma Jan 1999

Characterization And Improvement Of Eos Land Products Using Measurements At Ameriflux Grassland And Wheat Sites In The Arm/Cart Region: Research Annual Performance Report For Period March 1, 1999- February 29, 2000., E. A. Walter-Shea, S. B. Verma

School of Natural Resources: Documents and Reviews

No abstract provided.


Method For Identification Of Origins Of Replication And Genes Regulated By Dnaa In Bacteria, Olga G. Troyanskaya Jan 1999

Method For Identification Of Origins Of Replication And Genes Regulated By Dnaa In Bacteria, Olga G. Troyanskaya

Honors Theses

The study is focused on developing computer programs to identify origin of DNA replication based on analysis of total bacterial genomes, scoring regions for number of DnaA binding sites, AT content, DNA adenine methylase boxes, and integration host factors binding sites. The programs were tested on cyanobacterium Synechocystis, and several potential origins were identified. However, no one definite region could be located. Currently, software is being developed to analyze common motifs around the origins of all bacteria with known origins. Genes whose transcription could be regulated by DnaA were identified by searching for DnaA boxes preceding promoter regions.


Will Coaching Improve One's Math Score On The Scholastic Aptitude Test?, Judith B. Moore Jan 1999

Will Coaching Improve One's Math Score On The Scholastic Aptitude Test?, Judith B. Moore

The Corinthian

The Scholastic Aptitude Test (SAT) has long been a determining factor for admission into most of the nation's colleges and universities. Numerous studies have been conducted to question the reliability and predictive validity of SAT scores, yet they are still widely used. The widespread use of these scores in determining college admission is an indication that the SAT will be around for quite some time. For this reason and for personal reasons, I posed the following research question: "Will coaching improve one's math score on the Scholastic Aptitude Test?"


The Cytotoxicity And Mode Of Action Of 2,3,4-Trisubstituted Pyrroles And Related Derivatives In Human Tmolt4 Leukemia Cells, John T. Gupton, B. S. Burham, B. D. Byrd, K. E. Krumpe, C. Stokes, J. Shuford, S. Winkle, T. Webb, A. E. Warren, C. R. Barnes, J. Henry, I. H. Hall Jan 1999

The Cytotoxicity And Mode Of Action Of 2,3,4-Trisubstituted Pyrroles And Related Derivatives In Human Tmolt4 Leukemia Cells, John T. Gupton, B. S. Burham, B. D. Byrd, K. E. Krumpe, C. Stokes, J. Shuford, S. Winkle, T. Webb, A. E. Warren, C. R. Barnes, J. Henry, I. H. Hall

Chemistry Faculty Publications

4-Carbechoxy-l-methyl-2-phenacyl-3-phenylpyrrole (9), 4-carbethoxy-2-(4-methoxybcnzoyl)-3-(4-methoxyphcnyl)pyrrole (10) and 2-(4-methoxybenzoyl)-3,4-bis-(4-methoxyphenyl)pyrrole (11) proved to be potent cytotoxic agents against the growth of murine and human leukemias and lymphomas. Selective toxicity was demonstrated against the growth of solid tumors, e.g. human adenocarcinoma of the colon SW480 and ileum HCT-8, glioma U-87-MG, and rat UMR-106 osteosarcoma. A mode of action study in Tmolt4 leukemia cells demonstrated that the agents inhibited de novo purine synthesis at the regulatory sites PRPP-amido transferase, IMP dehydrogenase as well as dihydrofolate reductase resulting in significant inhibition of DNA synthesis in 60 min. Other biochemical sites …


A Woman's Field Is Made At Night: Gendered Land Rights And Norms In Burkina Faso, Michael Kevane, Leslie C. Gray Jan 1999

A Woman's Field Is Made At Night: Gendered Land Rights And Norms In Burkina Faso, Michael Kevane, Leslie C. Gray

Economics

Gendered social norms and institutions are important determinants of agricultural activities in southwestern Burkina Faso. This paper argues that gendered land tenure, in particular, has effects on equity and efficiency. The usual view of women as holders of secondary, or indirect, rights to land must be supplemented by a more nuanced understanding of tenure. Women's rights are in fact considerably more complex than the simple right to fields from their husbands. First, women's rights to property obtained from men may be coupled with other rights and obligations. In many ethnic groups, women have share rights to the harvest of their …


Weighting Unusual Feature Types, Nicholas Howe, Claire Cardie Jan 1999

Weighting Unusual Feature Types, Nicholas Howe, Claire Cardie

Computer Science: Faculty Publications

Feature weighting is known empirically to improve classification accuracy for k-nearest neighbor classifiers in tasks with irrelevant features. Many feature weighting algorithms are designed to work with symbolic features, or numeric features, or both, but cannot be applied to problems with features that do not fit these categories. This paper presents a new k-nearest neighbor feature weighting algorithm that works with any kind of feature for which a distance function can be defined. Applied to an image classification task with unusual set-like features, the technique improves classification accuracy significantly. In tests on standard data sets from the UCI repository, the …


Embedded Training For Complex Information Systems, Brant A. Cheikes Jan 1999

Embedded Training For Complex Information Systems, Brant A. Cheikes

Computer Science: Faculty Publications

One approach to providing affordable operator training in the workplace is to augment applications with intelligent embedded training systems (ETS). Intelligent embedded training is highly interactive: trainees practice realistic problem-solving tasks on the prime application with guidance and feedback from the training system. This article makes three contributions to the theory and technology of ETS design. First, we describe a framework based on Norman’s “stages of user activity” model for defining the instructional objectives of an ETS. Second, we demonstrate a non-invasive approach to instrumenting software applications, thereby enabling them to collaborate with an ETS. Third, we describe a method …


Computational Geometry Column 35, Joseph O'Rourke Jan 1999

Computational Geometry Column 35, Joseph O'Rourke

Computer Science: Faculty Publications

The subquadratic algorithm of Kapoor for finding shortest paths on a polyhedron is described.


Locked And Unlocked Polygonal Chains In 3d, Therese Biedl, Erik D. Demaine, Martin L. Demaine, Sylvain Lazard, Anna Lubiw, Joseph O'Rourke, Mark Overmars, Steve Robbins, Ileana Streinu, Godfried Toussaint, Sue Whitesides Jan 1999

Locked And Unlocked Polygonal Chains In 3d, Therese Biedl, Erik D. Demaine, Martin L. Demaine, Sylvain Lazard, Anna Lubiw, Joseph O'Rourke, Mark Overmars, Steve Robbins, Ileana Streinu, Godfried Toussaint, Sue Whitesides

Computer Science: Faculty Publications

In this paper, we study movements of simple polygonal chains in 3D. We say that an open, simple polygonal chain can be straightened if it can be continuously reconfigured to a straight sequence of segments in such a manner that both the length of each link and the simplicity of the chain are maintained throughout the movement. The analogous concept for closed chains is convexification: reconfiguration to a planar convex polygon. Chains that cannot be straightened or convexified are called locked. While there are open chains in 3D that are locked, we show that if an open chain has a …


Analytical Modeling Of Cake Filtration, Scott A. Wells Jan 1999

Analytical Modeling Of Cake Filtration, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

The specific resistance model of cake filtration is based on the assumption that the average cake resistance is constant over time. This implies also that the spatially average values of porosity and pressure differential are also constant over time since specific resistance is a function of both parameters.

An analytical cake filtration model based on Tiller (1975) was derived using constitutive properties of kaolin suspensions in distilled water. Constitutive properties were determined by experiments performed using high-energy X-rays and porewater pressure probes to determine the spatial and temporal distributions of porosity and porewater pressure. Using these constitutive properties, predictions were …


Impacts Of Agricultural Transformation On The Principal Karstic Regions Of France, Jean Nicod, Jean-Noël Salomon Jan 1999

Impacts Of Agricultural Transformation On The Principal Karstic Regions Of France, Jean Nicod, Jean-Noël Salomon

International Journal of Speleology

The recent extension of intensive agriculture on the karst plateaus has caused different types of impact: soil management, generalised and/or localised pollution. Yet paradoxically rural depopulation can also have negative impacts, which largely depend on the characteristics and the hydrological function of the different karst environments. They are often negative, particularly as far as the water quality is concerned, which is why protection measures are undertaken, either in a defined area for a catchment, or in the framework of regional parks. But this is not always the case, so it is appropriate to analyse the problem of karst pollution as …


Decelerating Nazca-South America And Nazca-Pacific Plate Motions, Edmundo O. Norabuena, Timothy H. Dixon, Seth Stein, Christopher G. A. Harrison Jan 1999

Decelerating Nazca-South America And Nazca-Pacific Plate Motions, Edmundo O. Norabuena, Timothy H. Dixon, Seth Stein, Christopher G. A. Harrison

School of Geosciences Faculty and Staff Publications

Space geodetic estimates of the rate of Nazca-South America convergence and Nazca-Pacific spreading averaging over several years show that present day rates are significantly slower than the 3 million year average NUVEL-1A model. The implied rates of deceleration are consistent with longer term trends extending back to at least 20 Ma, about the time of initiation of Andes growth, and may reflect consequences of ongoing subduction and construction of the Andes, e.g., increased friction and viscous drag on the subducted slab as the leading edge of South America thickens.


Agriculture, Landscape And Human Impact In Some Karst Areas Of Italy, Ezio Burri, Benedetta Castiglioni, Ugo Sauro Jan 1999

Agriculture, Landscape And Human Impact In Some Karst Areas Of Italy, Ezio Burri, Benedetta Castiglioni, Ugo Sauro

International Journal of Speleology

Italy is made up for about 1/5 of its surface by soluble rocks, which represent the arena of karst environments. The karst morpho-units, some hundreds, are mainly distributed inside the alpine structure of the Mediterranean mountains. A very large number of rock formations are present, different in facies, lithology, age, etc. Among these, carbonate rocks prevail, followed by gypsum and salt. Most of the carbonate rocks are limestones sedimented in a platform environment and they show a wide range of porosity, frequency of fractures and bedding planes. The climatic processes, the expression of some different sub-types of Mediterranean climate (from …


Zinc Mining Contamination And Sedimentation Rates Of Historical Overbank Deposits, Honey Creek Watershed, Southwest Missouri, Jason L. Carlson Jan 1999

Zinc Mining Contamination And Sedimentation Rates Of Historical Overbank Deposits, Honey Creek Watershed, Southwest Missouri, Jason L. Carlson

MSU Graduate Theses

Sediment-associated contaminants released by past mining activities in the Tri-State Lead and Zinc District in southwest Missouri pose a long-term risk to water quality. This study uses sedimentological and geochemical analyses to describe the relationships between mine contaminant dispersal and historical sedimentation patterns of the Honey Creek watershed ( 176 km2) which drains the Aurora Sub-district along the eastern boundary of the Tri-State District. This watershed has been subjected to an intense period of Pb-Zn mining that began in 1886, peaked in 1916, and ended by 1930. The objectives of this study are to: (1) determine the magnitude and distribution …


Modeling The Effects Of Doliolids On The Plankton Community Structure Of The Southeastern Us Continental Shelf, A. G. Edward Haskell, Eileen E. Hofmann, Gustav-Adolf Paffenhofer, Peter G. Verity Jan 1999

Modeling The Effects Of Doliolids On The Plankton Community Structure Of The Southeastern Us Continental Shelf, A. G. Edward Haskell, Eileen E. Hofmann, Gustav-Adolf Paffenhofer, Peter G. Verity

CCPO Publications

A model of the lower trophic levels that consists of a system of coupled ordinary differential equations was developed to investigate the time-dependent behavior of doliolid populations associated with upwelling features on the outer southeastern US continental shelf. Model equations describe the interactions of doliolids with two phytoplankton size fractions, five copepod developmental stages and a detrital pool. Additional equations describe nitrate and ammonia. Model dynamics are based primarily upon data obtained from field and laboratory experiments for southeastern US continental shelf plankton populations. Variations on a reference simulation, which represents average upwelling conditions without doliolids, were carried out to …


Water Resources Management Plan: Arches National Park & Canyonlands National Park, Utah, Lynn Cudlip, Kevin Berghoff, David Vana-Miller Jan 1999

Water Resources Management Plan: Arches National Park & Canyonlands National Park, Utah, Lynn Cudlip, Kevin Berghoff, David Vana-Miller

All U.S. Government Documents (Utah Regional Depository)

The National Park Service recognizes the importance of preserving, conserving, and protecting water resources within its boundaries. Water resources, whether as large as the Colorado River or as small as a seep in Ernie's Country of Canyonlands National Park, play a distinctive role in linking ecosystems and , in general, provide habitat for a number of organisms. To protect park water resources, the Natinoal Park Service initiated a Water REsources Planning Program in 1991. The planning program provides an essential step in developing a comprehensive understanding of a park's hydrological system and the complex resource issues which surround it. The …


A Case For Site Acclimation In The Reintroduction Of The Endangered Razorback Sucker (Xyrauchen Texanus), United States Geological Survey Jan 1999

A Case For Site Acclimation In The Reintroduction Of The Endangered Razorback Sucker (Xyrauchen Texanus), United States Geological Survey

All U.S. Government Documents (Utah Regional Depository)

Two site-acclimation studies (Mueller and Marsh 1998, Foster and Mueller 1999) were conducted in 1997 and 1998. The primary emphasis was habitat use and dispersal but we also examined if the rapid dispersal, typically associated with hatchery-produced razorback suckers (suckers), could be mitigated by allowing fish a period of time to recover from stocking-induced stress. Findings of those studies and existing physiological literature suggest that current stocking protocols may subject stocked fish to unnecessary behavioral or physiological stress that could impact performance and ultimately survival. This report presents those findings and recommends an evaluation of existing stocking procedures for the …


Description Of The Pelagic Zooplankton And Fish Communities Of Lakes Powell And Mead, United States Geological Survey Jan 1999

Description Of The Pelagic Zooplankton And Fish Communities Of Lakes Powell And Mead, United States Geological Survey

All U.S. Government Documents (Utah Regional Depository)

Fishery biologists from Arizona, Nevada, and Utah have been faced with the imposing dilemma of monitoring the pelagic fishery of Lakes Powell and Mead. Standard sampling procedures typically used to monitor shoreline fisheries are simply inadequate for the deep volumes of pelagic habitat found in these two reservoirs. Nearly a decade ago, Arizona and Nevada biologists recommended that hydroacoustics be used to monitor these communities (Persons and Dreyer 1987a,b, NDOW 1994). However, for various reasons an acoustical monitoring program was never fully implemented. This study represents the first attempt to describe the pelagic fishery of either reservoir using acoustic technology.


The Effect Of Mechanical Noise And Natural Sound On Visitor Experiences In Units Of The National Park System, Dr. James Gramann, National Park Service, U.S. Department Of The Interior Jan 1999

The Effect Of Mechanical Noise And Natural Sound On Visitor Experiences In Units Of The National Park System, Dr. James Gramann, National Park Service, U.S. Department Of The Interior

All U.S. Government Documents (Utah Regional Depository)

This paper reviews research on the effects of mechanical noise and natural sound on visitor experiences in national parks. Three approaches to studying noise impacts are described. Most noise research to date has addressed the impact of air-tour overflights on visitor experiences. these impacts are localized with significant percentages of visitors in some parks reporting interference with natural sounds from aircraft noise. Research also shows that unthreatening natural environments can have significant stress-reducing effects for many people. However, it is unclear if these effects are due to hearing the sounds of nature or to a combination of hearing and seeing …


South Manti Timber Salvage Draft Environmental Impact Statement, United States Forest Service Jan 1999

South Manti Timber Salvage Draft Environmental Impact Statement, United States Forest Service

All U.S. Government Documents (Utah Regional Depository)

The South Manti project area is located approximately 45 miles southwest of Price, Utah. The project area consists of approximately 24,597 acres of National Forest System lands within the southern portion of the Wasatch Plateau (Townships 19, 20, and 21 South; Range 4 East; SLM). This project was initiated in response to epidemic spruce beetle (Dendroctonus rufipennis) activity across the South Manti landscape. Extensive Engelmann spruce mortality has occurred as the result of epidemic spruce beetle populations. Representing over 10,000 acres, most of the spruce trees in the project area's Engelmann spruce-Subalpine fir cover type are dead or dying (70% …