Physical Sciences and Mathematics Commons^™

Disarticulation And Dissolution Of Crab Remains Across A Depth Gradient In The Bahamas: A Taphonomic Study, Rebecca A. Lincoln

Honors Papers

The fields of Paleontology and Paleoecology would not be complete without taphonomy, the study of the processes affecting organisms between death and fossilization. Taphonomy is important because it allows us to make more complete conjectures about prehistoric organisms and environments, and makes us aware of possible holes and biases in the fossil record due to highly destructive processes or the loss of delicate, non-resistant organisms. Studies on the processes affecting modern organisms have contributed greatly to the understanding of ancient processes; however, most of these studies are nearshore and short-term. What is lacking is information on the effects of these …

On Simplicial Commutative Algebras With Vanishing André-Quillen Homology, James M. Turner

University Faculty Publications and Creative Works

In this paper, we study the André-Quillen homology of simplicial commutative ℓ-algebras, ℓ a field, having certain vanishing properties. When ℓ has non-zero characteristic, we obtain an algebraic version of a theorem of J.-P. Serre and Y. Umeda that characterizes such simplicial algebras having bounded homotopy groups. We further discuss how this theorem fails in the rational case and, as an application, indicate how the algebraic Serre theorem can be used to resolve a conjecture of D. Quillen for algebras of finite type over Noetherian rings, having non-zero characteristic.

Small-Scale Variability Of Groundwater-Lake Interaction At Shingobee Lake, Minnesota, Hans F. Kishel

Theses and Dissertations

Groundwater discharge is an important contributor to the water budget of a lake. The variability of hydraulic parameters of lake and groundwater systems causes difficulties in estimating the contribution of groundwater to a lake water budget. This study attempts to show that amount of variability for a small portion of the lake and shore (8 x 15 meter section, starting approximately five meters from shore and extending nine meters into the lake).

Piezometers were installed at a depth of one half and one meter in nests at 70 locations in the rectangular study site. Water levels were collected from the …

Characterization Of Hyporheic Zone Processes Of A Northern Prairie Stream, David B. Rush

Theses and Dissertations

A hyporheic zone occurs beneath and adjacent to streams where surface water and groundwater mix. This zone is known to be a reservoir for solutes and a habitat for interstitial organisms. Hyporheic zone boundaries in the Tongue River, North Dakota, were investigated through examination of the physicochemical and biological gradients present in the stream channel and bank sediments. The effects of cattle grazing at the streamside interface of the riparian zone were also examined at two locations to determine land use impacts on the hyporheic zone.

Electrical conductivity (EC) and ammonium gradients were observed beneath the stream channel via nests …

The Hî² Index As An Age Indicator Of Old Stellar Systems: The Effects Of Horizontal-Branch Stars, Hyun Chul Lee, Suk Jin Yoon, Young Wook Lee

Physics and Astronomy Faculty Publications and Presentations

The strength of the Hβ index is computed for the integrated spectra of model globular clusters from the evolutionary population synthesis. For the first time, these models take into account the detailed systematic variation of horizontal-branch (HB) morphology with age and metallicity. Our models show that the Hβ index is significantly affected by the presence of blue HB stars. Because of the contribution from blue HB stars, the Hβ does not monotonically decrease as metallicity increases at a given age. Instead, it reaches a maximum strength when the distribution of HB stars is centered around 9500 K, the temperature at …

Ce-Qual-W2 Version 3: Hydrodynamic And Water Quality River Basin Modeling, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

CE-QUAL-W2 is a two-dimensional (longitudinal-vertical) water quality and hydrodynamic computer simulation model that was originally developed for deep, long, and narrow waterbodies. The current model, Version 2, has been used in over 200 river, reservoir/lake, and estuary applications throughout the U.S. and abroad. Version 2, though, cannot accommodate systems that have a significant sloping water surface since the vertical coordinate system is aligned with gravity and vertical accelerations are neglected. The governing equations for CE-QUAL-W2 were re-derived so that it could be applied to entire river basins including river-estuary, lake-river, and reservoir-river systems with channel slopes. This re-derivation is one …

Modeling The Bull Run River-Reservoir System, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

The City of Portland, Water Bureau currently operates 2 Bull Run reservoirs, Reservoir #2 and Reservoir #1 as a water supply source in the Bull Run watershed shown in Figure 1 and Figure 2. The Water Bureau wants to operate their water supply system in order to meet both water supply objectives and fish habitat objectives downstream of the Bull Run reservoirs in Bull Run River. In addition, a third Bull Run reservoir has been proposed as an additional water supply source. This reservoir also may be used to meet water supply and fish habitat objectives in Bull Run River. …

Boundary Quadrature Formulas And Their Applications, Tian-Xiao He

Tian-Xiao He

This chapter surveys the analytical approach for constructing multivariate numerical integration formulas that use only boundary points as evaluation points. The applications of boundary quadrature formulas to boundary value problems of partial differential equations are also discussed.

Evaluating The Effective Action, Br Holstein

Barry R Holstein

The use of effective field theory, in situations wherein the energy-momentum of light particles is much lower than the rest mass of heavy degrees of freedom, has become an important one in contemporary physics. Herein we examine various means by which this effective action can be evaluated, using the effective photon–photon interaction—the Euler–Heisenberg Lagrangian—as a pedagogical example.

Infrared Spectro-Electrochemistry, Mark Anderson, C. Douglas Taylor

Mark R. Anderson

The combination of infrared (IR) spectroscopy and electrochemistry in a single measurement has been an area of active research interest since the late 1960s. IR spectroelectrochemical experiments provide insight about interfacial electrochemical phenomena and/or oxidation–reduction reaction mechanisms that cannot be obtained using either technique individually. The power of the measurement is in the complementary nature of the spectroscopic and electrochemical information available when obtained simultaneously. The combination of measurements, however, requires compromise between the IR spectroscopy and the electrochemistry because of their different sampling requirements. The need for compromise illustrates the unique strengths and weaknesses of the combined spectroelectrochemical measurement. …

Interactive Real Analysis. / Glossary, Bert Wachsmuth

Bert Wachsmuth

No abstract provided.

Statistical Analysis Of Reliability, Maintainability And Supportability Data, Caroline Lubert

Caroline P Lubert

No abstract provided.

Clusterin Is An Atp-Independent Chaperone With Very Broad Substrate Specificity That Stabilizes Stressed Proteins In A Folding-Competent State, Stephen Poon, Simon Easterbrook-Smith, Mark Rybchyn, John Carver, Mark Wilson

Mark R Wilson

We recently reported that the ubiquitous, secreted protein clusterin has chaperone activity in vitro [Humphreys et al. (1999) J. Biol. Chem. 274, 6875−6881]. In this study, we demonstrate that clusterin (i) inhibits stress-induced precipitation of a very broad range of structurally divergent protein substrates, (ii) binds irreversibly via an ATP-independent mechanism to stressed proteins to form solubilized high molecular weight complexes, (iii) lacks detectable ATPase activity, (iv) when acting alone, does not effect refolding of stressed proteins in vitro, and (v) stabilizes stressed proteins in a state competent for refolding by heat shock protein 70 (HSP70). Furthermore, we show that, …

C1 Quadratic Macroelements And C1 Orthogonal Multiresolution Analyses In 2d, Tian-Xiao He

Tian-Xiao He

Each triangle of an arbitrary regular triangulation Δ of a polygonal region in R² is subdivided into twelve subtriangles by using three connecting lines joining three arbitrarily chosen points on its edges, three connecting lines from an arbitrarily chosen interior point in the triangle to its three vertices, and three connecting lines joining the points on the edges and the interior point. In this refinement, C¹ quadratic finite elements can be constructed. In this paper, we will give explicit Bezier coefficients of elements in terms of the parameters that describe function and first partial derivative values at vertices …

Rhapsody In White: A Victory For Mathematics, J. Bruning, A. Cantrell, R. Longhurst, D. Schwalbe, Stan Wagon

Stan Wagon, Retired

No abstract provided.

Making Connections Between Metallofullerenes And Fullerenes: Electrochemical Investigations, Mark Anderson, Harry Dorn, Steven Stevenson

Mark R. Anderson

The square-wave voltammetry for a series of related fullerenes and metallofullerenes measured in pyridine solutions containing 0.10 M tetra-n-butylammonium perchlorate is reported. Several dimetallic metallofullerenes, M2@Cx (where M=Sc or Er, and x=82 or 84), are found to have similar voltammetric responses regardless of metal identity or carbon number. Assignment of formal charges to the fullerene cage suggests that these metallofullerenes are isoelectronic and have related molecular orbital structures. The voltammetry of the empty C82 and D2d-C84 cages are also alike, but are different from the square-wave voltammetry of the C60, C70, and D2-C84. The similarity of the voltammetry for C82 …

Structural And Topographic Evolution Of The Central Transverse Ranges, California, From Apatite Fission- Track, (U-Th)/He And Digital Elevation Model Analyses, Ann Blythe, D Burbank, K Farley, E Fielding

Ann Blythe

No abstract provided.

Fe-Mg Carbonates As A Monitor Phase Of Carbon Dioxide And Oxygen Fugacity On Mars, Andrea Koziol

Andrea M. Koziol

Logic-Based Methods For Optimization: Combining Optimization And Constraint Satisfaction, John Hooker

John Hooker

No abstract provided.

Mirage Mirror On The Wall, T. Kosa, Peter Palffy-Muhoray

Peter Palffy-Muhoray

We discuss mirages formed near a sun-heated wall, and consider the underlying physics. The temperature and refractive index variations in air near the wall are estimated, and a simple approximate picture of ray propagation is presented. Estimates of the thermal decay length and ray curvature are compared with experimental observations.

Collaborative Activity Between Parietal And Dorso-Lateral Prefrontal Cortex In Dynamic Spatial Working Memory Revealed By Fmri, Vaibhav A. Diwadkar, Patricia A. Carpenter, Marcel Adam Just

Marcel Adam Just

No abstract provided.

Rapid Solidification: Fundamentals And Modeling, Guo-Xiang Wang, Vish Prasad

Dr. Guo-Xiang Wang

No abstract provided.

Automatic Segmentation And Indexing In A Database Of Bird Images, Madirakshi Das, R. Manmatha

R. Manmatha

The aim of this work is to index images in domain specific databases using colors computed from the object of interest only, instead of the whole image. The main problem in this task is the segmentation of the region of interest from the background. Viewing segmentation as a figure/ground segregation problem leads to a new approach - eliminating the background leaves the figure or object of interest. To find possible object colors, we first find background colors and eliminate them. We then use an edge image at an appropriate scale to eliminate those parts of the image which are not …

A Brief Biography Of Professor L.C. Hsu (Lizhi Xu), Tian-Xiao He

Tian-Xiao He

No abstract provided.

Systems Of Difference Equations With Asymptotically Constant Solutions, William F. Trench

William F. Trench

No abstract provided.

New Isotopic Evidence For Chronic Lead Contamination In The San Francisco Bay Estuary System: Implications For The Persistence Of Past Industrial Lead Emissions In The Biosphere, Douglas J. Steding, Charles E. Dunlap, A. Russell Flegal

Charles Dunlap

Measurements of lead isotope compositions in unfiltered San Francisco Bay waters from 1989 to 1998 have brought new insights into the cycling of anthropogenic lead in estuaries. Isotopic com- positions of lead in the shallow (<2 m) southern reach were essentially invariant (~90% derived from 1960s–1970s leaded gasoline) during the study period because of limited hydraulic flushing and the remobilization of lead from bottom sediments. In contrast, in the northern reach freshwater flushing from the San Joaquin and Sacramento rivers produced seasonal and decadal variations in lead isotope compositions. The seasonal shifts are attributed to advection of soils containing late 1980s gasoline lead into the bay during winter rains. Mass balance calculations indicate that only a small fraction (1–10%) of this leaded gasoline fallout from the late 1980s has been washed out of the San Joaquin and Sacramento rivers’ drainage basin by 1995. Superimposed on this seasonal cycling was a long-term systematic shift in the component of gasoline lead expressed in the river systems, with a small (~5–10%) decrease in the amount of 1960s–1970s gasoline lead in river and North Bay waters. The retention of gasoline lead in the river systems draining into the bay as well as San Francisco Bay sediments indicates that historic gasoline deposits may remain in the combined riparian/estuarine system for decades. Such a persistence is in contraindication to recent reports of rapid (annual) decreases in lead contamination in other environments, and the link between climate and contaminant transport suggests local or global climate change will have an impact on contaminant distribution and fate.

Past Leaded Gasoline Emissions As A Nonpoint Source Tracer In Riparian Systems: A Study Of River Inputs To San Francisco Bay, Charles E. Dunlap, Robin Bouse, A. Russell Flegal

Charles Dunlap

Variations in the isotopic composition of lead in 1995- 1998 river waters flowing into San Francisco Bay trace the washout of lead deposited in the drainage basin from leaded gasoline combustion. At the confluence of the Sacramento and San Joaquin rivers where they enter the Bay, the isotopic compositions of lead in the waters define a linear trend away from the measured historical compositions of leaded gas in California. The river waters are shifted away from leaded gasoline values and toward an isotopic composition similar to Sierra Nevadan inputs which became the predominant source of sedimentation in San Francisco Bay …

The Neural Basis Of Strategy And Skill In Sentence-Picture Verification, Erik D. Reichle, Patricia A. A. Carpenter, Marcel Adam Just

Marcel Adam Just

No abstract provided.

The Discovery-Oriented Approach To Organic Chemistry. 3. Boron-Trifluoride Catalyzed Rearrangement Of Cis- And Trans-Stilbene Oxides. An Exercise In 1H Nmr Spectroscopy For Sophomore Organic Laboratories, Ram S. Mohan, Erik A. Sgariglia, Regina Schopp, Kostas Gavardinas

Ram S. Mohan

Isolation Of Curcumin From Tumeric, Ram S. Mohan, Andrew M. Anderson, Matthew S. Mitchell

Ram S. Mohan

No abstract provided.