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2004

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Articles 4351 - 4380 of 4447

Full-Text Articles in Physical Sciences and Mathematics

Inter-Annual To Inter-Decadal Variability Of Upwelling And Anchovy Population Off Northern Chile, Jose L. Blanco-Garcia Jan 2004

Inter-Annual To Inter-Decadal Variability Of Upwelling And Anchovy Population Off Northern Chile, Jose L. Blanco-Garcia

OES Theses and Dissertations

The coastal ocean of northern Chile has persistent wind-driven upwelling that produces high nutrient and chlorophyll concentrations in a narrow band along the coast. The objective of this thesis is to study the low frequency temporal variability of the upwelling system, to understand the spatial and temporal changes in the wind field, and how these changes may affect the upwelling and anchovy variability. Data used in this thesis includes time series of wind, sea level, sea surface temperature, and atmospheric pressure at coastal stations, from 1960 to 2003, and oceanographic and acoustic cruises for the period 1993–2003. The time series …


A Study Of Pc-5 Ulf Oscillations, M K. Hudson, R E. Denton, M R. Lessard, E G. Miftakhova, R R. Anderson Jan 2004

A Study Of Pc-5 Ulf Oscillations, M K. Hudson, R E. Denton, M R. Lessard, E G. Miftakhova, R R. Anderson

Dartmouth Scholarship

A study of Pc-5 magnetic pulsations using data from the Combined Release and Radiation Effects Satellite (CRRES) was carried out. Three-component dynamic mag- netic field spectrograms have been used to survey ULF pul- sation activity for the approximate fourteen month lifetime of CRRES. Two-hour panels of dynamic spectra were exam- ined to find events which fall into two basic categories: 1) toroidal modes (fundamental and harmonic resonances) and 2) poloidal modes, which include compressional oscillations. The occurence rates were determined as a function of L value and local time. The main result is a comparable probabil- ity of occurence of …


Algebras With Inner Mb-Representation, Krzysztof Ciesielski Jan 2004

Algebras With Inner Mb-Representation, Krzysztof Ciesielski

Faculty & Staff Scholarship

We investigate algebras of sets, and pairs (A,I) consisting of an algebra A and an ideal I, which is a subset of A, that possess an inner MB-representation. We compare inner MB-representability of (A,I) with several properties of (A,I) considered by Baldwin. We show that A is inner MB-representable if and only if A =S(A \ H (A)), where S(.) is a Marczewski operation defined below and H consists of sets that are hereditarily in A. We study uniqueness issue of the ideal in that representation.


Continuous Images Of Big Sets And Additivity Of S0 Under Cpaprism, Krzysztof Ciesielski Jan 2004

Continuous Images Of Big Sets And Additivity Of S0 Under Cpaprism, Krzysztof Ciesielski

Faculty & Staff Scholarship

We prove that the Covering Property Axiom CPAprism, which holds in the iterated perfect set model, implies the following facts.

  • There exists a family G of uniformly continuous functions from R to [0,1] such that G has cardinality \omega1 < \continuum and for every subset S of R of cardinality \continuum there exists a g in G with g[S]=[0,1].
  • The additivity of the Marczewski's ideal s0 is equal to \omega1 < \continuum.


Limulus In The Limelight: Exploring An Ancient Species, John Tanacredi Ph.D. Jan 2004

Limulus In The Limelight: Exploring An Ancient Species, John Tanacredi Ph.D.

Faculty Works: CERCOM (1977-2016)

In an era when sports numbers shatter historical ceilings (especially in baseball) and fall by the wayside like fall leaves, a most enduring record of life continues to crawl along emerging from the sea early each spring pronouncing their incredible "record" of existences... over 350 million years. Now there is a number that even the rarified air of baseball salaries can admire. Yet, today the remarkable sea creature which endured over 100 million years of dramatically changing earth history prior to the existence of the dinosaurs, and which is comprised of only four species globally, is being tested for its …


Gated Electron Transfer As A Probe Of The Configurational Dynamics Of Peptide-Protein Complexes, Liu Liu, Jing Hong, Michael Y. Ogawa Jan 2004

Gated Electron Transfer As A Probe Of The Configurational Dynamics Of Peptide-Protein Complexes, Liu Liu, Jing Hong, Michael Y. Ogawa

Chemistry Faculty Publications

Gated electron-transfer measurements are used to probe the configurational dynamics of complexes formed between small metallopeptides and cytochrome c. The results show that that an apparently subtle chemical alteration of the metallopeptide produces significant changes to the dynamics of the peptide−protein complex.


A Comparison Of Land Use And Nonpoint Source Pollution In The Cedar River Tributaries In Iowa, Chad Levi Fields Jan 2004

A Comparison Of Land Use And Nonpoint Source Pollution In The Cedar River Tributaries In Iowa, Chad Levi Fields

Dissertations and Theses @ UNI

A comparative water analysis on major Cedar River tributaries was conducted to determine nutrient and sediment concentration, nutrient loads, and watershed land use during the spring and summer of 2002. The Cedar River watershed is located on a primarily agricultural land, and has a drainage area of20,242 km2. The watershed extends from southern Minnesota to southeastern Iowa, where it joins the Iowa River which subsequently flows into the Mississippi River. Past studies have concluded that the Cedar River contributes much of the nutrients entering the Mississippi River and the Gulf of Mexico. These nutrients then contribute to the zone of …


Speed-Up Collisions In Strong-Field Double Ionization, Stanley L. Haan, J. C. Cully, K. Hoekema Jan 2004

Speed-Up Collisions In Strong-Field Double Ionization, Stanley L. Haan, J. C. Cully, K. Hoekema

University Faculty Publications and Creative Works

We compare quantum and classical models of double ionization (DI) for aligned-electron helium in strong laser fields, considering specifically the role of recollision processes in which the returning electron travels in the direction of the laser force. Quantum studies show that for the knee region in our model a small but persistent portion of the total DI occurs through these speed-up collisions. We show that classical modeling displays similar collisions and reveals that with-the-force doubly ionizing collisions typically involve two-particle trajectories in which both electrons can be said to have been bound or very nearly bound at the zero of …


Analysis Of Photoassociation Spectra For Giant Helium Dimers, J. Léonard, A. P. Mosk, M. Walhout, P. Van Der Straten Jan 2004

Analysis Of Photoassociation Spectra For Giant Helium Dimers, J. Léonard, A. P. Mosk, M. Walhout, P. Van Der Straten

University Faculty Publications and Creative Works

A theoretical analysis was performed to interpret the spectra of long-range helium dimers produced by photoassociation in an ultracold gas of metastable helium atoms. The vibrational spectra for the purely long range molecular states was also calculated using adiabatic potentials obtained from perturbation theory. The results confirmed the lifetime of the 23P atomic state. The experimental data allowed for a test of tiny vibration-induced couplings between electronic and nuclear degrees of freedom.


Microstructures And Deformation In Some Fault Rocks From The Mcconnell Thrust At Mount Yamnuska (Alberta): Implications For Fluid Flow And Faulting And Cycles Of Strain-Hardening And Softening, Lowell Miyagi Jan 2004

Microstructures And Deformation In Some Fault Rocks From The Mcconnell Thrust At Mount Yamnuska (Alberta): Implications For Fluid Flow And Faulting And Cycles Of Strain-Hardening And Softening, Lowell Miyagi

Honors Papers

Fault rocks from the McConnell thrust consist of limestone mylonite, carbonate and shale cataclasites, and deformed sandstones. The limestone mylonite in the hanging wall mayor may not show different levels of cataclastic overprint. Just below these hanging wall rocks is a zone of comminuted material. This zone contains cataclasites that are produced by the mixing of hanging wall and footwall materials. Underneath this unit are the shale cataclasites of the footwall and beneath this are deformed sandstones that become progressively less deformed further from the fault zone. Based on microstructural evidence these rocks show cycles of mesoscopically brittle and ductile …


Epibiont Guilds As Paleoecological Tools In Environmental Analysis: An Example From Modern And Ordovician Shell Substrates, Stacy M. Boore Jan 2004

Epibiont Guilds As Paleoecological Tools In Environmental Analysis: An Example From Modern And Ordovician Shell Substrates, Stacy M. Boore

Honors Papers

Paleocommunities of encrusting organisms exhibit characteristics that allow comparisons of modern and fossil systems and subsequent environmental analyses. Encrusting organisms attach to a substrate that is generally limited in area. Interactions between bionts and the host organism, and bionts and the environment, are preserved on epibiont encrusted fossils. Modern biont communities from known environments can be compared to fossil biont communities in order to determine the ancient environment experienced by that fossil. Using epibionts as a tool in paleo-environmental analyses employs the somewhat problematic idea that the present can be used as a key to the past. I suggest that …


Generation Of The Transient Electrical And Spontaneous Magnetic Fields By Solid State Combustion, Karen S. Martirosyan, J. R. Claycomb, J. H. Miller Jr., D. Luss Jan 2004

Generation Of The Transient Electrical And Spontaneous Magnetic Fields By Solid State Combustion, Karen S. Martirosyan, J. R. Claycomb, J. H. Miller Jr., D. Luss

Physics and Astronomy Faculty Publications and Presentations

Experiments revealed that transient electric field intensities up to 2.5 V/cm were generated during the initial period of combustion synthesis of the ferromagnetic products before the maximum temperature was reached. This occurred when the iron particles were partially oxidized and the reaction product was mainly magnetite sFe3O4d. The electromagnetic field caused spontaneous magnetization of the product in the postcombustion zone. Magnetic field values up to 4 µT formed after the sample temperature fell below the Curie temperature and the initial reactants were completely converted to the ferromagnetic phase PbFe12O19. Increasing the volume of the samples increases the absolute residual magnetic …


Willamette River Basin Temperature Tmdl Model: Boundary Conditions And Model Setup, Robert Leslie Annear, Michael Lee Mckillip, Sher Jamal Khan, Chris Berger, Scott A. Wells Jan 2004

Willamette River Basin Temperature Tmdl Model: Boundary Conditions And Model Setup, Robert Leslie Annear, Michael Lee Mckillip, Sher Jamal Khan, Chris Berger, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

The State of Oregon Department of Environmental Quality (DEQ) is developing a TMDL for temperature in the Willamette River basin shown in Figure 1. The study area included the Willamette River and all major tributaries (except the Tualatin River where a TMDL process was already concluded). A large section of the Columbia River was also modeled to provide adequate boundary representation of tidal flows in the lower Willamette River. The Willamette River below the Oregon City Falls in the Portland metropolitan area has a typical diurnal tidal range of 1 m. The development of a dynamic model of temperature and …


Infrastructure For Performance Tuning Mpi Applications, Kathryn Marie Mohror Jan 2004

Infrastructure For Performance Tuning Mpi Applications, Kathryn Marie Mohror

Dissertations and Theses

Clusters of workstations are becoming increasingly popular as a low-budget alternative for supercomputing power. In these systems,message-passing is often used to allow the separate nodes to act as a single computing machine. Programmers of such systems face a daunting challenge in understanding the performance bottlenecks of their applications. This is largely due to the vast amount of performance data that is collected, and the time and expertise necessary to use traditional parallel performance tools to analyze that data.

The goal of this project is to increase the level of performance tool support for message-passing application programmers on clusters of workstations. …


Environmental Gradients, Community Boundaries, And Disturbance The Darlingtonia Fens Of Southwestern Oregon, Deborah A. Tolman Jan 2004

Environmental Gradients, Community Boundaries, And Disturbance The Darlingtonia Fens Of Southwestern Oregon, Deborah A. Tolman

Dissertations and Theses

The Darlingtonia fens, found on serpentine soils in southern Oregon, are distinct communities that frequently undergo dramatic changes in size and shape in response to a wide array of environmental factors. Since few systems demonstrate a balance among high water tables, shallow soils, the presence of heavy metals, and limited nutrients, conservative efforts have been made to preserve them. This dissertation investigates the role of fire on nutrient cycling and succession in three separate fens, each a different time since fire. I specifically analyze the spatial distributions of soil properties, the physical and ecological characteristics of ecotones between Jeffrey pine …


Light & Dark: The Hidden Wonders Of Buck Creek, Lee J. Florea Jan 2004

Light & Dark: The Hidden Wonders Of Buck Creek, Lee J. Florea

Earth, Environmental, and Atmospheric Sciences Faculty Publications

As early morning mists rise from the banks of its supple waters, beams of light penetrate the Buck Creek valley illuminating its beauty. While light illuminates most of the land, there are secret places, nestled within the forest where darkness reigns supreme. Places beyond the touch of the sun, beyond the influence of seasons. Here time is measured not in cycles of light but by the flow of water and fall of rock. These are the caves, conduits for water past and present. Nestled in the hills of south-central Kentucky the caves along Buck Creek provide the lifeblood for a …


Hydrochemical Variations During Flood Pulses In The South-West China Peak Cluster Karst: Impacts Of Caco3–H2o–Co2 Interactions, Chris Groves, Zaihua Liu, Daoxian Yuan, Joe Meiman, Guanghui Jiang, Shiyi He, Qiang Li Jan 2004

Hydrochemical Variations During Flood Pulses In The South-West China Peak Cluster Karst: Impacts Of Caco3–H2o–Co2 Interactions, Chris Groves, Zaihua Liu, Daoxian Yuan, Joe Meiman, Guanghui Jiang, Shiyi He, Qiang Li

Earth, Environmental, and Atmospheric Sciences Faculty Publications

High-resolution measurements of rainfall, water level, pH, conductivity, temperature and carbonate chemistry parameters of groundwater at two adjacent locations within the peak cluster karst of the Guilin Karst Experimental Site in Guangxi Province, China, were made with different types of multiparameter sonde. The data were stored using data loggers recording with 2 min or 15 min resolution. Waters from a large, perennial spring represent the exit for the aquifer's conduit flow, and a nearby well measures water in the conduit-adjacent, fractured media. During flood pulses, the pH of the conduit flow water rises as the conductivity falls. In contrast, and …


Development Of The Maryland Shoreline Inventory Methods And Guidelines For Wicomico County, Marcia Berman, Harry Berquist, Sharon Dewing, Carl Hershner, Helen Rea, Tamia Rudnicky, Daniel E. Schatt, David Weiss, Helen Woods Jan 2004

Development Of The Maryland Shoreline Inventory Methods And Guidelines For Wicomico County, Marcia Berman, Harry Berquist, Sharon Dewing, Carl Hershner, Helen Rea, Tamia Rudnicky, Daniel E. Schatt, David Weiss, Helen Woods

Reports

No abstract provided.


Diethylaluminum Chloride Mediated Vinylsilane Synthesis: Comparison Of Different Solvent Systems., Man Lung Kwan, Merle Battiste, Megan Macala, Sylvia Aybar, Nicholas James, Joseph Haoui Dec 2003

Diethylaluminum Chloride Mediated Vinylsilane Synthesis: Comparison Of Different Solvent Systems., Man Lung Kwan, Merle Battiste, Megan Macala, Sylvia Aybar, Nicholas James, Joseph Haoui

Man Lung Desmond Kwan

Aromatic ketones were converted to one-carbon elongated-vinylsilanes in a convenient one-pot operation via the Peterson protocol. Reactions were conducted in two different solvents for comparison: pentane and triethylamine. Results indicate that triethylamine appeared to be a more suitable solvent for such a transformation producing vinylsilanes with great chemo- and stereo-selectivity than pentane.


Committee On Climate Change And Sustainable Development: 2003 Annual Report, John Dernbach Dec 2003

Committee On Climate Change And Sustainable Development: 2003 Annual Report, John Dernbach

John C. Dernbach

No abstract provided.


On The Edge Set Of Graphs Of Lattice Paths, Lara Pudwell, Steven Klee, Rick Gillman Dec 2003

On The Edge Set Of Graphs Of Lattice Paths, Lara Pudwell, Steven Klee, Rick Gillman

Lara K. Pudwell

No abstract provided.


Underwater Terrain Reconstruction Using Sonar Data Taken From Multiple Vantage Points, Christopher Roman Dec 2003

Underwater Terrain Reconstruction Using Sonar Data Taken From Multiple Vantage Points, Christopher Roman

Christopher N. Roman

No abstract provided.


An Evaluation Of The Potential Of Atriplex Nummualria For Sheep Production In Arid Jordanian Rangelands, Raed Al-Tabini, A. Younger Dec 2003

An Evaluation Of The Potential Of Atriplex Nummualria For Sheep Production In Arid Jordanian Rangelands, Raed Al-Tabini, A. Younger

Raed Al-Tabini

No abstract provided.


On Cross Numbers Of Minimal Zero Sequences In Certain Cyclic Groups, Lara Pudwell, Scott Chapman, Paul Baginski, Kathryn Mcdonald Dec 2003

On Cross Numbers Of Minimal Zero Sequences In Certain Cyclic Groups, Lara Pudwell, Scott Chapman, Paul Baginski, Kathryn Mcdonald

Lara K. Pudwell

No abstract provided.


Reading, Writing, And Toxics: Children's Health, Academic Performance, And Environmental Justice In Los Angeles, Manuel Pastor, James Sadd, Rachel Morello-Frosch Dec 2003

Reading, Writing, And Toxics: Children's Health, Academic Performance, And Environmental Justice In Los Angeles, Manuel Pastor, James Sadd, Rachel Morello-Frosch

James Sadd

A significant body of previous research on environmental justice has demonstrated a disproportionate burden of environmental hazards on low-income and minority residents. In this paper we evaluate spatially indexed data on estimated respiratory and cancer risks associated with exposures to ambient air toxics to show that children of color in the Los Angeles Unified School District suffer potentially disparate health impacts, and that disparities in environmental risks may be associated with diminished school performance -- even after controlling for socioeconomic and demographic covariates that generally explain much of the variation in student scores. Remediating environmental health risks in distressed neighborhoods …


Synthesis, Crystal Structure And Thermoelectric Properties Of Β-K2bi8se13 Solid Solutions, Theodora Kyratsi, Duck-Young Chung, Jeff Dyck, Ctirad Uher, Sangeeta Lal, Sim Loo, Tim Hogan, John Ireland, Carl Kannewurf, Evripides Hatzikraniotis, Konstantinos Paraskevopoulos, Mercouri Kanatzidis Dec 2003

Synthesis, Crystal Structure And Thermoelectric Properties Of Β-K2bi8se13 Solid Solutions, Theodora Kyratsi, Duck-Young Chung, Jeff Dyck, Ctirad Uher, Sangeeta Lal, Sim Loo, Tim Hogan, John Ireland, Carl Kannewurf, Evripides Hatzikraniotis, Konstantinos Paraskevopoulos, Mercouri Kanatzidis

Jeffrey Dyck

Solid solution series of the type K2Bi8-xSbxSe13, K2-xRbxBi8Se13 as well as K2Bi8Se13-xSx were prepared and the distribution of the atoms (Bi/Sb, K/Rb and Se/S) on different crystallographic sites, the band gaps and their thermoelectric properties were studied. The distribution Se/S appears to be more uniform than the distribution of the Sb and Rb atoms in the β-K2Bi8Se13 structure that shows preference in specific sites in the lattice. Band gap is mainly affected by Sb and S substitution. Seebeck coefficient measurements showed n-type character for of all Se/S members. In the Bi/Sb series an enhancement of p-type character was observed. The …


Solvent-Free Conversion Of Alpha-Naphthaldehyde To 1-Naphthoic Acid And 1-Naphthalenemethanol: Application Of The Cannizzaro Reaction, John Esteb, Keith Gligorich, Stacy O'Reilly, Jeremy Richter Dec 2003

Solvent-Free Conversion Of Alpha-Naphthaldehyde To 1-Naphthoic Acid And 1-Naphthalenemethanol: Application Of The Cannizzaro Reaction, John Esteb, Keith Gligorich, Stacy O'Reilly, Jeremy Richter

John Esteb

The Cannizzaro reaction is routinely covered in organic textbooks, but owing to the shortage of suitable procedures for the undergraduate teaching laboratory, this reaction is seldom performed in a first-year organic chemistry class. In this experiment, powdered potassium hydroxide and α-naphthaldehyde are heated under solvent-free conditions to produce 1-naphthoic acid and 1-naphthalenemethanol in 86% and 79% yields, respectively. The solvent-free nature of this procedure greatly reduces the quantity of waste generated by students relative to the typical solvent-based method of preparation. Note:Link is to the article in a subscription database available to users affiliated with Butler University. Appropriate login information …


Hands-On Geometry, S. Sportsman, Shannon Driskell Dec 2003

Hands-On Geometry, S. Sportsman, Shannon Driskell

Shannon O.S. Driskell

Sportsman, S. (Co-PI), & Driskell, S. (Co-PI), Improving Teacher Quality State Grants Program, Ohio Board of Regents, $90,246


Fixed Point Theorems, Karen Saxe, Karine Moe Dec 2003

Fixed Point Theorems, Karen Saxe, Karine Moe

Karen Saxe

No abstract provided.


Windimurra Vanadium Deposit, Murchison Region, W.A., D Bolton, Jude Alexander Dec 2003

Windimurra Vanadium Deposit, Murchison Region, W.A., D Bolton, Jude Alexander

Jude Alexander

No abstract provided.