Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Faculty Publications

Discipline
Institution
Keyword
Publication Year
File Type

Articles 39601 - 39630 of 45766

Full-Text Articles in Entire DC Network

Measurements Of Ω And Λ From 42 High-Redshift Supernovae, S. Perlmutter, G. Aldering, G. Goldhaber, R. A. Knop, P. Nugent, P. G. Castro, S. Deustua, S. Fabbro, A. Goobar, D. E. Groom, I. M. Hook, A. G. Kim, M. Y. Kim, J. C. Lee, N. J. Nunes, R. Pain, C. R. Pennypacker, R. Quimby, C. Lidman, R. S. Ellis, M. Irwin, R. G. Mcmahon, P. Ruiz-Lapuente, N. Walton, B. Schaefer, B. J. Boyle, A. V. Filippenko, T. Matheson, A. S. Fruchter, N. Panagia, H. J.M. Newberg, W. J. Couch Jun 1999

Measurements Of Ω And Λ From 42 High-Redshift Supernovae, S. Perlmutter, G. Aldering, G. Goldhaber, R. A. Knop, P. Nugent, P. G. Castro, S. Deustua, S. Fabbro, A. Goobar, D. E. Groom, I. M. Hook, A. G. Kim, M. Y. Kim, J. C. Lee, N. J. Nunes, R. Pain, C. R. Pennypacker, R. Quimby, C. Lidman, R. S. Ellis, M. Irwin, R. G. Mcmahon, P. Ruiz-Lapuente, N. Walton, B. Schaefer, B. J. Boyle, A. V. Filippenko, T. Matheson, A. S. Fruchter, N. Panagia, H. J.M. Newberg, W. J. Couch

Faculty Publications

We report measurements of the mass density, ΩM, and cosmological-constant energy density, ΩΛ of the universe based on the analysis of 42 type Ia supernovae discovered by the Supernova Cosmology Project. The magnitude-redshift data for these supernovae, at redshifts between 0.18 and 0.83, are fitted jointly with a set of supernovae from the Calán/Tololo Supernova Survey, at redshifts below 0.1, to yield values for the cosmological parameters. All supernova peak magnitudes are standardized using a SN Ia light-curve width-luminosity relation. The measurement yields a joint probability distribution of the cosmological parameters that is approximated by the relation 0.8ΩM - 0.6ΩΛ …


The Long Isoform Uncoupling Protein-3 (Ucp3l) In Human Energy Homeostasis, W. K. Chung, A. Luke, R. S. Cooper, C. Rotini, A. Vidal-Puig, M. Rosenbaum, D. Gordon, S. M. Leal, S. Caprio, R. Goldsmith, A. L. Andreu, C. Bruno, S. Dimauro, M. Heo, W. L. Lowe, B. B. Lowell, D. B. Allison, R. L. Leibel Jun 1999

The Long Isoform Uncoupling Protein-3 (Ucp3l) In Human Energy Homeostasis, W. K. Chung, A. Luke, R. S. Cooper, C. Rotini, A. Vidal-Puig, M. Rosenbaum, D. Gordon, S. M. Leal, S. Caprio, R. Goldsmith, A. L. Andreu, C. Bruno, S. Dimauro, M. Heo, W. L. Lowe, B. B. Lowell, D. B. Allison, R. L. Leibel

Faculty Publications

The biological role(s) proposed for UCP3 in energy homeostasis have been based primarily upon amino acid sequence homology to UCP1. Spontaneous mutations of UCP3 have been described in humans, but not in rodents. The functional consequences—or lack thereof—of these mutations in humans will be of great importance in elucidating the biology of this protein. The results of two such studies are summarized here. © 1999 Stockton Press. All rights reserved.


Dynamics Of Formation Of Soliton Conductivity In A 2 D-Array Of Linear Chains Containing Commensurate Charge Density Waves Near The Contact With A Normal Metal, Yuriy V. Pershin Dr, Alexander S. Rozhavsky Jun 1999

Dynamics Of Formation Of Soliton Conductivity In A 2 D-Array Of Linear Chains Containing Commensurate Charge Density Waves Near The Contact With A Normal Metal, Yuriy V. Pershin Dr, Alexander S. Rozhavsky

Faculty Publications

We make a numerical study of the conversion of conduction electrons into charge density wave (CDW) topological solitons at the interface between a normal metal and a 2D-array of the CDW-carrying linear chains. The interplay of commensurability potential, interchain interaction, and electric field on the dynamics of soliton formation is studied. When the interchain interaction exceeds the commensurability energy, the dynamic mechanism of creation of fractionally charged solitons near the contact is suppressed and specific contact nonlinearity in transport current is not observed.


Creatine Supplementation Differentially Affects Maximal Isometric Strength And Time To Fatigue In Large And Small Muscle Groups, William J. Vincent, Steven F. Loy, Richard L. Urbanski, Ben B. Yaspelkis Jun 1999

Creatine Supplementation Differentially Affects Maximal Isometric Strength And Time To Fatigue In Large And Small Muscle Groups, William J. Vincent, Steven F. Loy, Richard L. Urbanski, Ben B. Yaspelkis

Faculty Publications

Ten physically active, untrained, college-aged males (26.4 ± 5.8 years old) received creatine (CR. 5 g creatine monohydrate + 3 g dextrose) and placebo (PLA, 7 g dextrose) supplementation four times per day for 5 days in a doubleblind, randomized, balanced, crossover design. Performance was assessed during maximal and three repeated submaximal bouts of isometric knee extension and handgrip exercise. CR supplementation significantly increased (p < .05) maximal isometric strength during knee extension but not during handgrip exercise. CR supplementation increased time to fatigue during each of the three bouts of submaximal knee extension and handgrip exercise when compared to the PLA trials. These findings suggest that CR supplementation can increase maximal strength and time to fatigue during isometric exercise. However, the improvements in maximal isometric strength following CR supplementation appear to be restricted to movements performed with a large muscle mass.


Synthesis And Experimental Testing Of A Nonlinear Optimal Tracking Controller, Timothy Mclain, Randal W. Beard, Christopher A. Bailey Jun 1999

Synthesis And Experimental Testing Of A Nonlinear Optimal Tracking Controller, Timothy Mclain, Randal W. Beard, Christopher A. Bailey

Faculty Publications

This paper presents a novel approach for developing tracking controllers for nonlinear systems. The approach involves the numerical solution, by Galerkin approximation, of the time-varying Hamilton-Jacobi-Bellman (HJB) equation and results in a nonlinear controller approximating the optimal tracking control law for a specified desired trajectory and cost function. Experimental results are presented for a nonlinear pendulum system.


Overview: Nonlinear Dynamics Related To Polymeric Systems, Irving R. Epstein, John A. Pojman Jun 1999

Overview: Nonlinear Dynamics Related To Polymeric Systems, Irving R. Epstein, John A. Pojman

Faculty Publications

No abstract provided.


The Winogradsky Column & Biofilms: Models For Teaching Nutrient Cycling & Succession In An Ecosystem, Delia Castro Anderson, Rosalina V. Hairston Jun 1999

The Winogradsky Column & Biofilms: Models For Teaching Nutrient Cycling & Succession In An Ecosystem, Delia Castro Anderson, Rosalina V. Hairston

Faculty Publications

No abstract provided.


Period-Doubling Behavior In Frontal Polymerization Of Multifunctional Acrylates, Jonathan Masere, Felicia Stewart, Timothy Meehan, John A. Pojman Jun 1999

Period-Doubling Behavior In Frontal Polymerization Of Multifunctional Acrylates, Jonathan Masere, Felicia Stewart, Timothy Meehan, John A. Pojman

Faculty Publications

Front dynamics in the frontal polymerization of two multifunctional acrylate monomers, 1,6-hexanediol diacrylate (HDDA) and trimethylolpropane ethoxylate triacrylate (TMPTA), with Lupersol 231 [1,1-di(t-butylperoxy)-3,3,5-trimethylcyclohexane] as the initiator, are studied. In most frontal polymerization systems, the dynamics are associated with a planar front propagating through the sample. However, in some cases, front behavior can be altered: the front becomes nonplanar characterized by complex patterns like spin modes and pulsations. To determine how these periodic and aperiodic modes arise, reactant solutions consisting of HDDA diluted with diethyl phthalate (DEP) and TMPTA diluted with dimethyl sulfoxide (DMSO) were used in the study. …


Can Shame, Guilt, Or Stigma Be Taught? Why Credit-Focused Debtor Education May Not Work, A. Mechele Dickerson Jun 1999

Can Shame, Guilt, Or Stigma Be Taught? Why Credit-Focused Debtor Education May Not Work, A. Mechele Dickerson

Faculty Publications

No abstract provided.


Toboggan-Based Intelligent Scissors With A Four-Parameter Edge Model, William A. Barrett, Eric N. Mortensen Jun 1999

Toboggan-Based Intelligent Scissors With A Four-Parameter Edge Model, William A. Barrett, Eric N. Mortensen

Faculty Publications

Intelligent Scissors is an interactive image segmentation tool that allows a user to select piece-wise globally optimal contour segments that correspond to a desired object boundary. We present a new and faster method of computing the optimal path by over-segmenting the image using tobogganing and then imposing a weighted planar graph on top of the resulting region boundaries. The resulting region-based graph is many times smaller than the previous pixel-based graph, thus providing faster graph searches and immediate user interaction. Further, tobogganing provides an new systematic and predictable framework for computing edge model parameters, allowing subpixel localization as well as …


Under Fire: A Look At Recent Controversy Over The Sabbath, Samuele Bacchiocchi Jun 1999

Under Fire: A Look At Recent Controversy Over The Sabbath, Samuele Bacchiocchi

Faculty Publications

No abstract provided.


Knowledge Discovery In Bibliographic Databases - Introduction, Jian Qin, M. Jay Norton Jun 1999

Knowledge Discovery In Bibliographic Databases - Introduction, Jian Qin, M. Jay Norton

Faculty Publications

No abstract provided.


Knowledge Discovery In Databases, Melanie J. Norton Jun 1999

Knowledge Discovery In Databases, Melanie J. Norton

Faculty Publications

KNOWLEDGE DISCOVERY IN DATABASES (KDD) revolves around the investigation and creation of knowledge, processes, algorithms, and the mechanisms for retrieving potential knowledge from data collections. Related issues include data collection, database design, the description of entries in the database using the most appropriate representation, and data quality. This article is an introductory overview of knowledge discovery in databases. The rationale and environment of its development and applications are discussed. Issues related to database design and collection are reviewed.


The Changing Tradition Of Constitutional Review Of Sign And Billboard Regulation, Ronald H. Rosenberg Jun 1999

The Changing Tradition Of Constitutional Review Of Sign And Billboard Regulation, Ronald H. Rosenberg

Faculty Publications

No abstract provided.


Model Predictive Satisficing Fuzzy Logic Control, Richard L. Frost, Michael A. Goodrich, Wynn C. Stirling Jun 1999

Model Predictive Satisficing Fuzzy Logic Control, Richard L. Frost, Michael A. Goodrich, Wynn C. Stirling

Faculty Publications

Model-predictive control, which is an alternative to conventional optimal control, provides controller solutions to many constrained and nonlinear control problems. However, even when a good model is available, it may be necessary for an expert to specify the relationship between local model predictions and global system performance. We present a satisficing fuzzy logic controller that is based on a receding control horizon, but which employs a fuzzy description of system consequences via model predictions. This controller considers the gains and losses associated with each control action, is compatible with robust design objectives, and permits flexible defuzzifier design. We demonstrate the …


Multiscale Image Registration Using Scale Trace Correlation, Bruce B. Hansen, Bryan S. Morse Jun 1999

Multiscale Image Registration Using Scale Trace Correlation, Bruce B. Hansen, Bryan S. Morse

Faculty Publications

This paper presents a method for registering images at different magnifications (scales) by treating the problem not only as one of scaling the image coordinates but also as one inherently involving multiresolution information. While some existing methods for multiresolution registration do consider the way the resolution (scale) affects the image, they often consider the image one scale at a time, using geometric properties within that scale. Others use multiscale information, usually to produce more robust results, but only to register same-magnification images (e.g., stereo). A scale trace is the set of values that a single pixel takes on as magnification …


Metallicity Calibration Of A Ddo Cn Index And Other Low-Resolution Indices For G And K Stars, B. J. Taylor May 1999

Metallicity Calibration Of A Ddo Cn Index And Other Low-Resolution Indices For G And K Stars, B. J. Taylor

Faculty Publications

Metallicity calibrations of low-resolution parameters are potentially useful for (at least) two problems: the properties of moving groups, and the supermetallicity problem in K giants. In this paper, metallicity calibrations are derived for six sets of parameters. One of these parameters is the DDO CN index deltaCN. This parameter and three others are calibrated for use with evolved G and K stars. Two additional sets of low-resolution parameters are calibrated for use with G and K dwarfs. The calibrations are derived by comparing the input data with two catalogs of homogenized high-dispersion results from diverse authors (see Taylor 1995, 1999a). …


Electric Monopole Transitions From Low Energy Excitations In Nuclei, J. L. Wood, E. F. Zganjar, C. De Coster, K. Heyde May 1999

Electric Monopole Transitions From Low Energy Excitations In Nuclei, J. L. Wood, E. F. Zganjar, C. De Coster, K. Heyde

Faculty Publications

Electric monopole (E0) properties are studied across the entire nuclear mass surface. Besides an introductory discussion of various model results (shell model, geometric vibrational and rotational models, algebraic models), we point out that many of the largest E0 transition strengths, p2(E0), are associated with shape mixing. We discuss in detail the manifestation of E0 transitions and present extensive data for single-closed shell nuclei, vibrational nuclei, well-deformed nuclei, nuclei that exhibit sudden ground-state changes, and nuclei that exhibit shape coexistence and intruder states. We also pay attention to light nuclei, odd-A nuclei, and illustrate a suggested relation between p2(E0) and isotopic …


The X-Ray Transient Xte J2012+381, R. I. Hynes, P. Roche, P. A. Charles, M. J. Coe May 1999

The X-Ray Transient Xte J2012+381, R. I. Hynes, P. Roche, P. A. Charles, M. J. Coe

Faculty Publications

We present optical and infrared observations of the soft X-ray transient (SXT) XTE J2012+381 and identify the optical counterpart with a faint red star heavily blended with a brighter foreground star. The fainter star is coincident with the radio counterpart and appears to show weak Ha emission and to have faded between observations. The RXTE All Sky Monitor light curve of XTE J2012+381 is unusual for an SXT in that after an extended linear decay, it settled into a plateau state for about 40 days before undergoing a weak mini-outburst. We discuss the nature of the object and suggest similarities …


Oxygen Permeation Through Composite Oxide-Ion And Electronic Conductors, Kevin Huang, Michael Schroeder, John B. Goodenough May 1999

Oxygen Permeation Through Composite Oxide-Ion And Electronic Conductors, Kevin Huang, Michael Schroeder, John B. Goodenough

Faculty Publications

Oxygen permeation through composites consisting of four well-known oxide-ion conductors and a noble metal, Pd or Ag, is reported. The oxides were Zr0.9Y0.1O1.95 (YSZ), (Bi1.75Y0.25O3)0.95(CeO2)0.05 (BYC5), Ce0.8Sm0.2O1.9 (SSC), and La0.8Sr0.2Ga0.83Mg0.17O2.815 (LSGM). The results show that (BYC5 + Ag) yields the highest oxygen permeation flux, but the composite deteriorates with time. The composites (SSC + Pd), (LSGM + Pd), and (YSZ + Pd) give stable, but relatively lower oxygen permeation flux …


Co-Infection With Opportunistic Pathogens Promotes Human Immunodeficiency Virus Type 1 Infection In Macrophages, Sharon M. Wahl, Teresa Greenwell-Wild, Gang Peng, Hollie Hale-Donze, Jan M. Orenstein May 1999

Co-Infection With Opportunistic Pathogens Promotes Human Immunodeficiency Virus Type 1 Infection In Macrophages, Sharon M. Wahl, Teresa Greenwell-Wild, Gang Peng, Hollie Hale-Donze, Jan M. Orenstein

Faculty Publications

Human immunodeficiency virus type 1 (HIV-1) infection is dependent on susceptible host cells that express both CD4 and chemokine co-receptors. The co-receptor CCR5 is associated with primary infection by macrophage-tropic virus isolates, whereas CXCR4 is commonly associated with T cell- and dual- tropic viruses. Once infected, lymphocytes and macrophages may replicate HIV- 1 or harbor latent virus, depending on environmental factors and cellular activation. Immune activation is often associated with viremia, which is consistent with enhanced infection and viral replication in activated cells harboring virus. In this regard, opportunistic infections activate the immune system with the detrimental sequelae of enhanced …


Dissolved Organic Carbon Cycling In A Subtropical Seagrass-Dominated Lagoon, Susan Ziegler, Ronald Benner May 1999

Dissolved Organic Carbon Cycling In A Subtropical Seagrass-Dominated Lagoon, Susan Ziegler, Ronald Benner

Faculty Publications

The cycling of dissolved organic matter (DOM) and its significance to ecosystem metabolism was studled over a 16 mo period in a Thalassia testudjnum dominated meadow. The benthos was usually net autotrophic (annual gross primary production to respiration ratio [P:R] = 1.3) while water column respiration (R) exceeded gross primary production (annual P:R = 0.3). Net fluxes of dissolved organic carbon (DOC) from the benthos primarily occurred in the light (0 to 18 mmol C m-2 d-1) and from seagrass-dominated areas, suggesting that release of DOC was mainly due to seagrass exudation. Net benthic DOC fluxes measured …


The Mean Spherical Approximation For A Dipolar Yukawa Fluid, Douglas Henderson, Dezso Boda, Istvan Szalai, Kwong-Yu Chan May 1999

The Mean Spherical Approximation For A Dipolar Yukawa Fluid, Douglas Henderson, Dezso Boda, Istvan Szalai, Kwong-Yu Chan

Faculty Publications

The dipolar hard sphere fluid (DHSF) is a useful model of a polar fluid. However, the DHSF lacks a vapor–liquid transition due to the formation of chain-like structures. Such chains are not characteristic of real polar fluids. A more realistic model of a polar fluid is obtained by adding a Lennard–Jones potential to the intermolecular potential. Very similar results are obtained by adding a Yukawa potential, instead of the Lennard–Jones potential. We call this fluid the dipolar Yukawa fluid (DYF). We show that an analytical solution of the mean spherical approximation (MSA) can be obtained for the DYF. Thus, the …


William The Liberator, Jeffrey Rogers Hummel May 1999

William The Liberator, Jeffrey Rogers Hummel

Faculty Publications

No abstract provided.


Characterization Of Hypoxia: Topic 1 Report For The Integrated Assessment On Hypoxia In The Gulf Of Mexico, Nancy N. Rabalais, R. Eugene Turner, Dubravko Justic, Quay Dortch, William J. Wiseman May 1999

Characterization Of Hypoxia: Topic 1 Report For The Integrated Assessment On Hypoxia In The Gulf Of Mexico, Nancy N. Rabalais, R. Eugene Turner, Dubravko Justic, Quay Dortch, William J. Wiseman

Faculty Publications

No abstract provided.


Stratified Volume Diffractive Optical Elements As High Efficiency Gratings, Gregory P. Nordin, D. M. Chambers May 1999

Stratified Volume Diffractive Optical Elements As High Efficiency Gratings, Gregory P. Nordin, D. M. Chambers

Faculty Publications

We propose stratified volume diffractive optical elements as a new type of diffractive optical element that is capable of functioning as a high-efficiency grating in applications with requirements not suited to traditional holographic or diffractive optical techniques. In this approach, diffractive optical fabrication methods are used to construct an optical structure that emulates volume grating behavior. We discuss the diffraction properties of stratified volume diffractive optical elements and compare them with those used previously in both volume holographic optical elements and stratified volume holographic optical elements. A systematic design process is then presented for deriving structure parameters. We illustrate this …


Cryosphere Applications Of Nscat Data, David G. Long, Mark R. Drinkwater May 1999

Cryosphere Applications Of Nscat Data, David G. Long, Mark R. Drinkwater

Faculty Publications

Though designed to measure vector winds over the ocean, new imaging techniques facilitate the use of NASA scatterometer data (NSCAT) in cryosphere studies. NSCAT provides data of unprecedented coverage, resolution, and quality which, when coupled with the scatterometer image reconstruction with filtering (SIRF) algorithm, enables images of O at resolutions approaching 8 km over stationary targets. Such images are useful in ice mapping and classification, and multidecadal studies are possible by comparison with Seasat Scatterometer (SASS) data. The utility of NSCAT data in polar ice studies is illustrated through a review of two cryosphere applications of NSCAT data: (1) sea-ice …


The Religious Right In Court: The Decision Making Of Christian Evangelicals In State Supreme Courts, Donald R. Songer, Susan J. Tabrizi May 1999

The Religious Right In Court: The Decision Making Of Christian Evangelicals In State Supreme Courts, Donald R. Songer, Susan J. Tabrizi

Faculty Publications

Much has been written recently about the emergence of evangelicals and others often labeled the "new Religious Right" in American politics. However, little attention has been paid to whether officials who have been socialized in the denominations characterized as being part of this Religious Right actually behave differently in office from those brought up in other religious traditions. The present study begins such an inquiry by examining differences in the voting behavior of state supreme court justices in three issue areas. Evangelical justices were found to be significantly more conservative than mainline Protestant, Catholic, and Jewish justices in death penalty, …


Annotated Bibliography Of Research In The Teaching Of English, Deborah Brown, Wayne Martino, Gert Rijlaarsdam, Anne D'Antonio Stinson, Melissa E. Whiting May 1999

Annotated Bibliography Of Research In The Teaching Of English, Deborah Brown, Wayne Martino, Gert Rijlaarsdam, Anne D'Antonio Stinson, Melissa E. Whiting

Faculty Publications

Twice a year, in the May and November issues, RTE publishes a selected bibliography of recent research in the teaching of English, Most of the studies appeared during the six-month period preceding the compilation of the bibliography (July through December; 1998, for the present bibliography), but some studies that appeared earlier are occasionally included. The listing is selective; we make no attempt to include all research and research-related studies that appeared in the period under review Comments on the bibliography and suggestions about items for inclusion may be directed to the bibliography editors. We encourage you to send your suggestions …


Simulations Of Snow Distribution And Hydrology In A Mountain Basin, Melannie D. Hartman, Jill S. Baron, Richard B. Lammers, Donald W. Cline, Larry E. Band, Glen E. Liston, Christina L. Tague May 1999

Simulations Of Snow Distribution And Hydrology In A Mountain Basin, Melannie D. Hartman, Jill S. Baron, Richard B. Lammers, Donald W. Cline, Larry E. Band, Glen E. Liston, Christina L. Tague

Faculty Publications

We applied a version of the Regional Hydro‐Ecologic Simulation System (RHESSys) that implements snow redistribution, elevation partitioning, and wind‐driven sublimation to Loch Vale Watershed (LVWS), an alpine‐subalpine Rocky Mountain catchment where snow accumulation and ablation dominate the hydrologic cycle. We compared simulated discharge to measured discharge and the simulated snow distribution to photogrammetrically rectified aerial (remotely sensed) images. Snow redistribution was governed by a topographic similarity index. We subdivided each hillslope into elevation bands that had homogeneous climate extrapolated from observed climate. We created a distributed wind speed field that was used in conjunction with daily measured wind speeds to …