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2000

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High-Performance Liquid Chromatographic Separation Of Enantiomers Of Synthetic Amino Acids On A Ristocetin A Chiral Stationary Phase, Antal Péter, Gabriella Török, Daniel W. Armstrong, Géza Tóth, Dirk Tourwé Dec 2000

High-Performance Liquid Chromatographic Separation Of Enantiomers Of Synthetic Amino Acids On A Ristocetin A Chiral Stationary Phase, Antal Péter, Gabriella Török, Daniel W. Armstrong, Géza Tóth, Dirk Tourwé

Chemistry Faculty Research & Creative Works

A macrocyclic glycopeptide, ristocetin A, was used as chiral stationary phase for the high-performance liquid chromatographic separation of enantiomers of 28 unnatural amino acids, such as analogues of phenylalanine, tyrosine and tryptophan, and analogues containing 1,2,3,4-tetrahydroisoquinoline, tetraline or 1,2,3,4-tetrahydro-2-carboline skeletons. Excellent resolutions were achieved for most of the investigated compounds by using reversed-phase or a new polar-organic mobile phase system. The conditions of separation were optimized by variation of the mobile phase composition, temperature and flowrate. Copyright (C) 2000 Elsevier Science B.V.

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Unitarized Pseudoscalar Meson Scattering Amplitudes In Three Flavor Linear Sigma Models, Joseph Schechter, Deirdre Black, Amir H. Fariborz, Sherif Moussa, Salah Nasri Dec 2000

Unitarized Pseudoscalar Meson Scattering Amplitudes In Three Flavor Linear Sigma Models, Joseph Schechter, Deirdre Black, Amir H. Fariborz, Sherif Moussa, Salah Nasri

Physics - All Scholarship

The three flavor linear sigma model is studied as a ``toy model'' for understanding the role of possible light scalar mesons in the \pi \pi, \pi K and \pi \eta scattering channels. The approach involves computing the tree level partial wave amplitude for each channel and unitarizing by a simple K-matrix prescription which does not introduce any new parameters. If the renormalizable version of the model is used there is only one free parameter. While this highly constrained version has the right general structure to explain \pi \pi scatteirng, it is ``not quite'' right. A reasonable fit can be made …

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Clemson Commencement Program, December 2000, Clemson University Dec 2000

Clemson Commencement Program, December 2000, Clemson University

Clemson Commencement Programs

No abstract provided.

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Further Investigation Of The Time Delay, Magnification Ratios, And Variability In The Gravitational Lens 0218 + 357, A. S. Cohen, J. N. Hewitt, C. B. Moore, Deborah B. Haarsma Dec 2000

Further Investigation Of The Time Delay, Magnification Ratios, And Variability In The Gravitational Lens 0218 + 357, A. S. Cohen, J. N. Hewitt, C. B. Moore, Deborah B. Haarsma

University Faculty Publications and Creative Works

High-precision VLA flux density measurements for the lensed images of 0218 + 357 yield a time delay of 10.1 +1.5-1.6 days (95% confidence). This is consistent with independent measurements carried out at the same epoch by Biggs and colleagues in 1999, lending confidence to the robustness of the time delay measurement. However, since both measurements make use of the same features in the light curves, it is possible that the effects of unmodeled processes, such as scintillation or microlensing, are biasing both time delay measurements in the same way. Our time delay estimates result in confidence intervals that are somewhat …

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Phase Diagram Of Three-Dimensional Dynamical Triangulations With A Boundary, Simon Catterall, Simeon Warner, Ray Renken Dec 2000

Phase Diagram Of Three-Dimensional Dynamical Triangulations With A Boundary, Simon Catterall, Simeon Warner, Ray Renken

Physics - All Scholarship

We use Monte Carlo simulation to study the phase diagram of three-dimensional dynamical triangulations with a boundary. Three phases are indentified and characterized. One of these phases is a new, boundary dominated phase; a simple argument is presented to explain its existence. First-order transitions are shown to occur along the critical lines separating phases.

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Academic Policy Advisory Committee Meeting Minutes, December 19, 2000, Minnesota State University Moorhead Dec 2000

Academic Policy Advisory Committee Meeting Minutes, December 19, 2000, Minnesota State University Moorhead

Academic Policy Advisory Committee

No abstract provided.

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Higher Twist Contributions To R-Hadron Phenomenology In The Light Gluino Scenario, Thomas D. Gutierrez, R. Vogt, J. F. Gunion Dec 2000

Higher Twist Contributions To R-Hadron Phenomenology In The Light Gluino Scenario, Thomas D. Gutierrez, R. Vogt, J. F. Gunion

Physics

The open light gluino window allows non-trivial higher-twist gluino contributions to the proton wave function. Using a two-component model originally developed for charm hadroproduction, higher-twist intrinsic gluino contributions to final-state R-hadron formation are shown to enhance leading-twist production in the forward xnF region. We calculate R-hadron production at Pnlab=800 GeV in pp, pBe, and pCu interactions with light gluino masses of 1.2, 1.5, 3.5, and 5.0 GeV.

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Campus Connection, December 18, 2000, Vol. 2 No. 8, California State University, Monterey Bay Dec 2000

Campus Connection, December 18, 2000, Vol. 2 No. 8, California State University, Monterey Bay

Campus Connection

Community Day of Learning to Focus on University Learning Requirements -- CSUMB Updates Emergency Preparedness Plan -- Faculty/Staff Profile: Meet Richard Bains -- CSUMB Recruitment Effort Continues for High Profile Positions -- Copyright Guide on ATMS Website -- NEWS BRIEFS -- CALENDAR -- HCOM Starts Oral History Website -- 15th Annual Free Christmas Dinner at Monterey Fairgrounds

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Making Classical And Quantum Canonical General Relativity Computable Through A Power Series Expansion In The Inverse Cosmological Constant, Rodolfo Gambini, Jorge Pullin Dec 2000

Making Classical And Quantum Canonical General Relativity Computable Through A Power Series Expansion In The Inverse Cosmological Constant, Rodolfo Gambini, Jorge Pullin

Faculty Publications

Casting ordinary general relativity as a perturbative theory in Λ-1 and starting with background theory in which Λ → ∞ allows one to explicitly compute nondegenerate physical quantum states and observables. The technique is applicable in the theory in general and also in mini-super-space models. In the general theory, the calculations are well defined and tractable, but quite involved. This opens up a program for the quantization of the gravitational field that is well defined computationally and allows contact with the physical observables of the theory, a key ingredient in the road to finding a theory with a semiclassical regime …

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Grand Valley Forum, Volume 025, Number 21, December 18, 2000, Grand Valley State University Dec 2000

Grand Valley Forum, Volume 025, Number 21, December 18, 2000, Grand Valley State University

2000-2001, Volume 25

Grand Valley Forum is Grand Valley State's faculty and staff newsletter, published from 1976 to the present.

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Using Three-Dimensional Cubes In The Development Of Number Sense And Spatial Reasoning Of First Grade Students, Deborah R. Parrish-Hill Dec 2000

Using Three-Dimensional Cubes In The Development Of Number Sense And Spatial Reasoning Of First Grade Students, Deborah R. Parrish-Hill

Mathematical and Computing Sciences Masters

In this study of six first grade students, my initial goal was to observe and describe the varying developmental levels of spatial reasoning and number sense through which these students would progress as they solved increasingly complex tasks and activities involving one-inch, three-dimensional, primary-colored cubes. These are the types of cubes used in studies by Battista ( 1998) and that are in most primary classrooms. Based upon those observations, my ultimate goal was to demonstrate that when young students have meaningful early experiences with one-inch, three-dimensional cubes, they will be able to reach New York State's benchmarked standards (see Appendix …

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An Evaluation Of The S2ia Switched-Current Architecture For (Delta)(Sigma) Modulator Adcs, Andre Botha Dec 2000

An Evaluation Of The S2ia Switched-Current Architecture For (Delta)(Sigma) Modulator Adcs, Andre Botha

Theses

Switched-Current (SI) is a design methodology by which discrete time, current mode, analog circuits can be implemented using standard digital CMOS processes, allowing the addition of analog signal processing circuits, analog to digital converters (ADCs), digital to analog converters (DACs) and other analog and mixed-signal circuits to otherwise digital only microchips without the need and expense of any extra fabrication steps. SI circuits operate by employing a secondary effect in CMOS circuits, a transistor's gate capacitance, to store charge and thus form a current memory cell. A current memory cell is one of the basic building blocks found in most …

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The Savannah River Site: Site Description, Land Use And Management History, David L. White, Karen F. Gaines Dec 2000

The Savannah River Site: Site Description, Land Use And Management History, David L. White, Karen F. Gaines

Publications

The 78,000-ha Savannah River Site, which is located in the upper Coastal Plain of South Carolina along the Savannah River, was established as a nuclear production facility in 1951 by the Atomic Energy Commission. The site’s physical and vegetative characteristics, land use history, and the impacts of management and operations are described. Aboriginal and early European settlement was primarily along streams, where much of the farming and timber cutting have occurred. Woodland grazing occurred in the uplands and lowlands. Land use intensity increased after the Civil War and peaked in the 1920s. Impacts from production of cotton and corn, naval …

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Lady Eagles & Eagles Basketball Games From December 17, 2000 And January 4, 2001, Morehead State University. Office Of Athletics. Dec 2000

Lady Eagles & Eagles Basketball Games From December 17, 2000 And January 4, 2001, Morehead State University. Office Of Athletics.

Morehead State Sports Team Programs

The official game program from the December 17, 2000 to January 4, 2001 basketball games of Morehead State University.

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Competency-Based Education: Teaching And Assessing Oral Communication In Fairbanks, Alaska High Schools, Diane Blair Barnett Dec 2000

Competency-Based Education: Teaching And Assessing Oral Communication In Fairbanks, Alaska High Schools, Diane Blair Barnett

Communication

Nationwide developments in the area of educational standards and accountability have produced a movement toward competency-based education in which teachers are increasingly tasked with facilitating the competencies within these developing standards. As a result, professionals in the Communication discipline have an opportunity to apply their knowledge of effective communication practices to provide benefits for students and teachers. The first phase of this study examined State and local educational standards in areas of speaking, listening, and group communication. Local and State standards identified as most closely aligned with standards developed by Communication professionals served as the basis for developing a questionnaire …

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Nitrogen Oxide Photochemistry In Marine Air Over The Eastern Pacific, Barbara Elisabeth Trost Dec 2000

Nitrogen Oxide Photochemistry In Marine Air Over The Eastern Pacific, Barbara Elisabeth Trost

Chemistry and Biochemistry

Models predict that photochemistry is the primary contribution to the observed spring surface ozone maxima in the Northern Hemisphere. Nitrogen oxides (NOx) are the limiting reagents for photochemical ozone production. This fact leads to an apparent paradox, because the short lifetime of NOx should lead to a low mixing ratio of NOx far from source regions. However, chemical reservoirs of NOx such as peroxyacetyl nitrate (PAN) may provide a transport pathway for delivering NOx to 'clean' marine Pacific air masses. A coastal site in Washington, was chosen to investigate the relationship of NOx, PAN and ozone in marine air from …

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Rayleigh Lidar Studies Of The Arctic Middle Atmosphere, Laura Jeanette Cutler Dec 2000

Rayleigh Lidar Studies Of The Arctic Middle Atmosphere, Laura Jeanette Cutler

Engineering

Rayleigh lidar allows us to measure density and temperature structure of the atmosphere at heights from approximately 35 to 80 kilometers. A Rayleigh lidar was installed at Poker Flat Research Range in November of 1997 and has been operated routinely since. This thesis presents an engineering analysis of the lidar system performance and a scientific analysis of the data obtained. The engineering analysis considers the receiver and transmitter alignment of the lidar system and the signal quality of the lidar data. The scientific analysis considers the retrieval of density and temperature profiles under a range of geophysical conditions. This study …

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Design And Simulation Of Flight Computer Using Vhdl For Arim-1 Sounding Rocket Payload, Anirban Chowdhury Dec 2000

Design And Simulation Of Flight Computer Using Vhdl For Arim-1 Sounding Rocket Payload, Anirban Chowdhury

Engineering

Atmospheric Refractive Index Measurement-1 (ARIM-1) is a sounding rocket payload designed to collect information regarding atmospheric turbulence. ARIM-1 is designed to make high-resolution (4 samples per centimeter) differential temperature measurements of the atmosphere to determine the structure of atmospheric turbulence and hence it's refractive index. The rocket's flight computer schedules and manages data acquisition from various payload sub-systems and transmits this acquired data to the ground station. The goal of this work is to develop a custom design for this flight computer using Very High Speed Integrated Circuit Hardware Description Language (VHDL). This thesis presents simulation and hardware requirements for …

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Use Of Beaufort Sea As Feeding Habitat By Bowhead Whales (Balaena Mysticetus) As Indicated By Stable Isotope Ratios, Sang Heon Lee Dec 2000

Use Of Beaufort Sea As Feeding Habitat By Bowhead Whales (Balaena Mysticetus) As Indicated By Stable Isotope Ratios, Sang Heon Lee

Marine Biology

The feeding habitats of the Western Arctic bowhead whales (Balaena mysticetus) during summer are generally known, but the precise amounts of food consumed from the eastern Beaufort Sea (EBS) are not known. [Alpha]13C and [alpha]15N ratios in whale tissues were used to estimate the amounts of food required from EBS. The feeding strategies of adults and subadults were also compared. For all whales, the [alpha]13C values in muscle sampled in fall were not significantly different from those in the muscle sampled in spring, indicating most food of adults and subadults comes from the Bering/Chukchi seas. The ¹³C data from baleen …

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Spatial-Temporal Variation In Reproduction And Site Fidelity Of Spectacled Eiders On The Yukon-Kuskowkim Delta, Alaska, Christine Leigh Moran Dec 2000

Spatial-Temporal Variation In Reproduction And Site Fidelity Of Spectacled Eiders On The Yukon-Kuskowkim Delta, Alaska, Christine Leigh Moran

Biological Sciences

In response to recent decline, we compared migration and nesting chronology, nest success, and clutch size of spectacled eiders nesting at Kigigak Island with those nesting on Kashunuk River to better understand regulation of the spectacled eider breeding population on Y-K Delta. We also examined and compared subpopulation relationships between nest site fidelity and breeding performance. We examined the relationship between female age and distance moved between consecutive year nest sites. Clutch sizes were comparable between the two sites and declined seasonally with older females laying earlier and larger clutches. Mayfield nest success was higher due to lower predation and …

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Habitat Selection By Calving Caribou Of The Central Arctic Herd, 1980-95, Scott Adrian Wolfe Dec 2000

Habitat Selection By Calving Caribou Of The Central Arctic Herd, 1980-95, Scott Adrian Wolfe

Biological Sciences

Habitat selection by calving caribou (Rangifer tarandus granti) of the Central Arctic Herd, Alaska, was assessed in relation to distance from roads, vegetation type, relative plant biomass (NDVI; Normalized Difference Vegetation Index), accumulation of plant biomass during early lactation (NDVIrate), snow cover, and terrain ruggedness. From 183 calving sites of 96 radio collared- females, 1980-95, calving distribution was estimated in reference (no development) and treatment (oilfields present) zones east and west of the Sagavanirktok River, respectively. In the reference zone, caribou regularly selected wet-graminoid vegetation, above-median NDVIrate, and non-rugged terrain; concentrated calving remained in habitats with zonal average NDVI on …

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Effects Of Migratory Geese On Plant Communities And Nitrogen Dynamics In An Alaskan Salt Marsh, Amy Beach Zacheis Dec 2000

Effects Of Migratory Geese On Plant Communities And Nitrogen Dynamics In An Alaskan Salt Marsh, Amy Beach Zacheis

Biological Sciences

Herbivory is an integral component of ecosystems that impacts plant communities and ecosystem processes, and affects forage availability and quality for the herbivore. I investigated the effects of lesser snow geese (Anser caerulescens caerulescens) and Canada geese (Branta canadensis) on two salt marsh communities, a sedge meadow and an herb meadow, in Cook Inlet, Alaska. Geese used the marshes during spring migration for a brief period, and foraging intensity was low compared to other goose-grazing systems. Seventy percent of the snow goose diet was on belowground plant tissues, whereas 92% of the Canada goose diet was on aboveground shoots. In …

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Systematics Of Beringian Threespine Sticklebacks, John S. Chythlook Dec 2000

Systematics Of Beringian Threespine Sticklebacks, John S. Chythlook

Biological Sciences

In Pleistocene Beringia, large-scale glaciations exposed high latitude species to variable environmental conditions that created disjunct populations of terrestrial and marine species. The general nature of the dynamic biogeographic history of Beringia can be assessed by studying genetic patterns across many Beringian organisms. Mitochondrial DNA sequences were used to study the phylogenetic and phylogeographic structure of the threespine stickleback, Gasterosteus aculeatus. A 714 bp fragment of the cytochrome b gene was sequenced from 66 individuals from 17 locations extending from southeast Alaska northwest to coastal Siberia. These data were combined with 36 homologous cyt-b sequences from a previous study to …

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Survival And Brood Rearing Ecology Of Emperor Geese, Joel A. Schmutz Dec 2000

Survival And Brood Rearing Ecology Of Emperor Geese, Joel A. Schmutz

Biological Sciences

Emperor Geese (Chen canagica) breed on the Yukon-Kuskokwim Delta in an area inhabited by three other goose species. Whereas populations of other geese increased since the mid 1980s, Emperor Goose numbers remained low. Because survival and habitat selection by broods of Emeperor Geese had not been studied previously and numbers of predatory Glaucous Gulls (Larus hyperboreus) had recently increased, I studied brood rearing ecology of Emperor Geese during 1993-1996 to assess whether this seasonal period could be limiting population growth. Survival of goslings to 30 days varied among years from 0.32 to 0.70 and was primarily influenced by mortality during …

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Genetic Engineering And Characterization Of Lysr-Type Transcriptional Regulators, Honghong Sun Dec 2000

Genetic Engineering And Characterization Of Lysr-Type Transcriptional Regulators, Honghong Sun

Biological Sciences

This thesis describes research aimed at understanding the structure and function of LysR-type transcriptional regulators. I studied two LysR-type proteins. One from the archaeon Methanococcus jannaschii, MJ-LysR. The other is from Burkholderia cepacia, DgdR. The MJ-LysR is the first putative LysR-type transcriptional regulator found in archaea. It is surprising that a prokaryotic transcriptional regulator is present in archaea, whose basal transcription machinery and RNA polymerase are more closely related to those of eukaryotes. To elucidate the structure and function of M-LysR protein, the gene was subcloned and expressed in E. coli. The gene product was isolated and purified by heat …

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Experimental And Economic Evaluation Of Gtl Fluid Flow Properties And Effect On Taps, Hariharan Ramakrishnan Dec 2000

Experimental And Economic Evaluation Of Gtl Fluid Flow Properties And Effect On Taps, Hariharan Ramakrishnan

Engineering

In this study, procedures are outlined to recondition and sample crude oil from high-pressure Welker cylinders. Standard laboratory procedures are developed to determine viscosity and density properties of crude oil, GTL and their mixtures. The steps needed to ensure Quality Assurance and Project Plan (QAPjp) is given in detail. A calibration macro is written to automate viscometer calibration calculations. A preliminary economic model is developed to evaluate GTL transportation options. Viscosity and density are measured for various samples at different temperatures. The reproducibility of the results is found to be within 5%. Batching is more preferable then blending for the …

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The Ecology Of The Arctic Char And The Dolly Varden In The Becharof Lake Drainage, Alaska, Brendan P. Scanlon Dec 2000

The Ecology Of The Arctic Char And The Dolly Varden In The Becharof Lake Drainage, Alaska, Brendan P. Scanlon

Fisheries

Becharof Lake is home to both Arctic char (Salvelinus alpinus) and the closely related Dolly Varden (Salvelinus malma), two species known not only to be similar in appearance but also to exhibit similar life histories. The body morphometry, otolith microchemistry, and stomach contents of both species were studied in fish collected from May to September 1998. Morphometric and meristic analysis revealed clear separation in body structure between the two species, as well as potential sub-populations within each species. Otolith microchemistry revealed incidences of anadromy and non-anadromy in both species. Stomach content analysis revealed a broad feeding niche but smaller ranges …

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Inversion Of Focal Mechanism Data For The Directions Of Stress Near Redoubt Volcano, Alaska, John Jairo Sánchez-Aguilar Dec 2000

Inversion Of Focal Mechanism Data For The Directions Of Stress Near Redoubt Volcano, Alaska, John Jairo Sánchez-Aguilar

Geosciences

No abstract provided.

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Fault-Hosted Au Mineralization, Ester Dome, Alaska, Cheryl E. Cameron Dec 2000

Fault-Hosted Au Mineralization, Ester Dome, Alaska, Cheryl E. Cameron

Geosciences

The Rhyolite gold prospect near Fairbanks, Alaska, appears to be different from most intrusion-related Au depositions within the Fairbanks area (e.g., Ryan Lode and Fort Knox), as it is located along a low-angle fault and is spatially associated with a quartz monozonite sill. A 1:60,000 scale geologic map was prepared using soil samples, airborne geophysical data, and mapping based on core and surface samples collected during 1998 and 1999. Mineralization does not appear to be temporally related to the quartz-monzodiorite sill, although mineralized fluids apparently used the sill as a pathway. ⁴⁰Ar/³⁹Ar dates of chloritized biotite from the intrusive ( …

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Commencement Program 2000 December, Gcsu Special Collections Dec 2000

Commencement Program 2000 December, Gcsu Special Collections

Commencement Programs

No abstract provided.

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